HABITAT

MANAGEMENT PLAN Bombay Hook National Wildlife Refuge MAY 2020

Habitat Management Plans (HMPs) are dynamic working documents that provide refuge managers with a decision-making process, a long-term vision for managing refuge habitats, and ensure continuity and consistency for habitat management on refuge lands. HMPs include goals, objectives, and strategies needed to accomplish refuge purposes and achieve the refuge long-term vision. These plans detail program levels that are sometimes above current budget and resource allocations. As such, HMPs are primarily for strategic planning and program prioritization purposes. HMPs do not constitute a commitment for staffing increases, operational and maintenance increases, or funding for future land acquisition. On an annual basis, refuge staff use the HMP to develop an Annual Habitat Work Plan that identifies the specific habitat management strategies and prescriptions, alongside the operational needs.

Habitat Management Plan for the Bombay Hook National Wildlife Refuge Approvals Action Signature/Name Date

Prepared By:

Coastal Delaware NWR Complex Supervisory Wildlife Biologist

Submitted By:

Coastal Delaware NWR Complex Project Leader

Reviewed By:

Division of Natural Resources and Conservation Planning Chief

Reviewed By:

Refuge Supervisor - South

Approved By:

Refuge Chief

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EXECUTIVE SUMMARY

Bombay Hook National Wildlife Refuge (NWR, refuge) was first established in the 1937 when lands were purchased with Duck Stamp funds to allow for a resting and feeding area for migratory and wintering waterfowl. Today, the refuge is located along the Delaware Bay and encompasses 16,162 acres of coastal marsh habitat, forested, freshwater wetland, grassland, and shrubland communities. This Habitat Management Plan (HMP) provides a long-term vision and specific guidance on managing the refuge’s habitats over the next 15 years (2020 to 2035). Refuge forests, both upland and wetland, will be expanded through restoration, while existing mature forest will be managed to improve wildlife habitat conditions. The three large freshwater impoundments will continue to be seasonally managed for the benefit of migrating and wintering shorebirds and waterfowl, as well as other native wildlife. Additional small seasonally managed wetlands will be created, and existing natural freshwater wetlands will be preserved. Early successional habitat will be reduced in acreage, but improved in quality through proactive management. The refuge’s extensive tidal salt marsh and associated fringing pockets of beach habitat will continue to be mostly passively managed however, when feasible, the refuge will pursue restoration efforts to improve ecological integrity of these habitats. Refuge staff initiated development of this HMP in 2018 to resolve high priority habitat management issues, including the opportunity to increase forested habitat on the refuge, while also strategically managing early successional habitat. Additionally, this HMP will help inform related step-down habitat management plans. The HMP is intended to be revisited as needed or every 15 years, with management strategies informed by research investigations and inventory and monitoring activities.

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TABLE OF CONTENTS

CHAPTER 1. INTRODUCTION ...... 1-1 Bombay Hook National Wildlife Refuge ...... 1-1 Scope of Habitat Management Plan ...... 1-2 Mission Mandates ...... 1-2 1.3.1 U.S. Fish and Wildlife Service ...... 1-2 National Wildlife Refuge System...... 1-3 Coastal Delaware National Wildlife Refuge Complex ...... 1-3 Bombay Hook National Wildlife Refuge ...... 1-4 Relationship to Other Plans and Guidance ...... 1-4 Federal Policies and Guidance ...... 1-4 Multi-stakeholder Conservation Initiatives and Regional Plans...... 1-5 Bombay Hook National Wildlife Refuge-Specific Plans ...... 1-7 CHAPTER 2. EXISTING CONDITIONS ...... 2-11 Landscape Setting ...... 2-11 Land Management History ...... 2-14 Pre-Refuge Land Use ...... 2-15 USFWS Stewardship ...... 2-15 Climate ...... 2-20 Air Quality ...... 2-20 General Description of Vegetative Communities ...... 2-20 Coastal Habitats ...... 2-26 Forested Habitats ...... 2-27 Freshwater Habitats ...... 2-28 Grassland and Shrubland Habitats ...... 2-29 Wildlife ...... 2-29 Birds ...... 2-29 Mammals ...... 2-31 Reptiles and Amphibians ...... 2-31 Invertebrates ...... 2-31 Fish...... 2-31 Special Status Species ...... 2-32 Aquatic Resources / Water Quality ...... 2-32 Geology ...... 2-32 Soils ...... 2-33 Threats to Management and Conservation ...... 2-33 Threat Characterization ...... 2-33 CHAPTER 3. RESOURCES OF CONCERN ...... 3-1 3.1 Introduction ...... 3-1 3.2 Identification of Resources of Concern ...... 3-1 Identification of Biological Integrity, Diversity, and Environmental Health ...... 3-2 Defining Biological Integrity, Diversity, and Environmental Health ...... 3-2 Identifying BIDEH at Bombay Hook NWR ...... 3-2 Priority Resources of Concern ...... 3-9 Priority Resources of Concern Selection ...... 3-9 Bombay Hook NWR Priority ROC Species and Relation to Refuge BIDEH...... 3-16 Priority Habitats ...... 3-19 CHAPTER 4. HABITAT GOALS, OBJECTIVES, AND MANAGEMENT STRATEGIES ...... 4-1 Defining HMP Goals and Objectives ...... 4-1 Habitat Management Goals ...... 4-1 Habitat Management Objectives and Adaptive Management ...... 4-1

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Management Strategies Common to All Refuge Habitats and Objectives ...... 4-8 Herbivory Management Strategies ...... 4-8 Human Intrusions and Disturbance ...... 4-8 Invasive Species Control Strategies ...... 4-8 Climate Change Adaptation Strategies ...... 4-9 Habitat Management Objectives, Strategies, and Rationales ...... 4-11 Goal 1. Forested Habitats ...... 4-11 Goal 2. Freshwater Wetlands ...... 4-16 Goal 3. Coastal Salt Marsh Habitats ...... 4-21 Goal 4. Early Successional Upland Habitats ...... 4-25 Inventory and Monitoring Planning ...... 4-28 CHAPTER 5. MANAGEMENT UNIT DESCRIPTIONS ...... 5-1 CHAPTER 6. REFERENCES CITED ...... 6-1

List of Appendices Appendix A. Draft Environmental Assessment for the Implementation of the Habitat Management Plan at Bombay Hook National Wildlife Refuge ...... A Appendix B. Comprehensive Resources of Concern (ROC) List ...... B Appendix C. Planning Team ...... C

List of Figures Figure 1-1. Bombay Hook National Wildlife Refuge ...... 1-1 Figure 1-2. Using the Habitat Management Plan for Annual Habitat Work Planning ...... 1-9 Figure 2-1 Refuge Location Relative to Delaware Bay Region NWRs ...... 2-12 Figure 2-2. Natural Areas and Corridors in Vicinity of Bombay Hook NWR ...... 2-13 Figure 2-3. Bombay Hook NWR History ...... 2-14 Figure 2-4. Legacy of Wetland Management Activities on Bombay Hook NWR ...... 2-17 Figure 2-5. Existing Habitat Conditions for Bombay Hook NWR Overview ...... 2-22 Figure 2-6. Existing Habitat Conditions for Bombay Hook NWR North ...... 2-23 Figure 2-7. Existing Habitat Conditions for Bombay Hook NWR South ...... 2-24 Figure 2-8. Threats Influencing Habitat Condition and Management on Bombay Hook NWR* ...... 2-35 Figure 4-1. Habitat Management Objectives Hierarchy for the Bombay Hook NWR...... 4-3 Figure 4-2. Overview of Planned Habitat Types for Bombay Hook NWR ...... 4-5 Figure 4-3. Overview of Planned Habitat Types for Bombay Hook NWR ...... 4-6 Figure 4-4. Overview of Planned Habitat Types for Bombay Hook NWR ...... 4-7 Figure 4-5. Strategic Management of Invasive Plants ...... 4-10 Figure 5-1. Habitat Management Units (HMU) at Bombay Hook NWR...... 5-2 Figure 5-2. Fisher Tract HMU at Bombay Hook NWR ...... 5-3 Figure 5-3. Dutch Neck HMU at Bombay Hook NWR ...... 5-4 Figure 5-4. Headquarters Area Managed Impoundments HMU at Bombay Hook NWR ...... 5-5 Figure 5-5. Headquarters Area Early Successional HMU at Bombay Hook NWR ...... 5-6

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Figure 5-6. Air Force Tract HMU at Bombay Hook NWR...... 5-7 Figure 5-7. Steamboat Landing HMU at Bombay Hook NWR...... 5-8 Figure 5-8. Salt Marsh HMU at Bombay Hook NWR...... 5-9

List of Tables Table 1-1. Plans Consulted During Bombay Hook NWR HMP Process ...... 1-5 Table 2-1. Past Management Actions at Bombay Hook NWR ...... 2-19 Table 2-2. Nomenclature of Habitats Observed on Bombay Hook NWR...... 2-25 Table 2-3. Summary of Current Refuge HMP Broad Habitat Types* ...... 2-26 Table 2-4. International Union for Conservation of Nature Threat Category Considerations ...... 2-34 Table 2-5. Problematic Species on Bombay Hook NWR ...... 2-39 Table 2-6. Predicted Change in Land Categories by 2100 Given Simulated Scenarios of Eustatic Sea Level Rise* ...... 2-41 Table 3-1 Summary of Habitats that Represent Existing BIDEH at Bombay Hook NWR ...... 3-3 Table 3-2 Habitat Requirements for Bombay Hook NWR Priority Resources of Concern ...... 3-12 Table 3-3 Priority ROC and Other Benefiting Candidate ROC at Bombay Hook NWR ...... 3-18 Table 3-4 Priority Habitats at Bombay Hook NWR ...... 3-20

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ACRONYMS AND ABBREVIATIONS

AHWP Annual Habitat Work Plan BCR Bird Conservation Region BIDEH Biological Integrity, Diversity, and Environmental Health CCC Civilian Conservation Corps DNREC Delaware Division of Natural Resources and Environmental Control DFW Division of Fish and Wildlife DSL Designing Sustainable Landscapes DE WAP Delaware Wildlife Action Plan HMP Habitat Management Plan I&M Inventory and Monitoring IMP Inventory and Monitoring Plan IPM Integrated Pest Management IUCN International Union for Conservation of Nature LCC Landscape Conservation Cooperatives NABCI North American Bird Conservation Initiative NEPARC Northeast Partners in Amphibian and Reptile Conservation NVCS National Vegetation Classification System NWR National Wildlife Refuge NWRS National Wildlife Refuge System PIF Partners in Flight ROC Resources of Concern ROCSTAR Resources of Concern Selection Tool for America’s Refuges SHARP Saltmarsh Habitat and Aviation Research Program SHC Strategic Habitat Conservation SLR Sea Level Rise SPCC Spill Prevention, Control, and Countermeasures TMDL Total Maximum Daily Load USFWS United States Fish and Wildlife Service WRIA Water Resources Inventory and Assessment WMA Wildlife Management Area

Habitat Management Plan for Bombay Hook National Wildlife Refuge

CHAPTER 1. INTRODUCTION BOMBAY HOOK NATIONAL WILDLIFE REFUGE Bombay Hook National Wildlife Refuge (NWR, refuge) is managed by the United States Fish and Wildlife Service (USFWS, Service) within the Coastal Delaware NWR Complex as part of the National Wildlife Refuge System (Refuge System). The refuge currently encompasses 16,162 acres providing a diversity of upland and wetland habitats for migrating and wintering waterfowl, migrating shorebirds, salt marsh specialist species, and other species of conservation concern. The refuge is relatively flat with most elevations less than 10 feet above sea level. Seventy-five percent of the refuge consists of tidal salt marsh intersected by winding rivers, guts, and creeks. Landward of the marsh are forested, freshwater wetland, grassland, and shrubland communities. The refuge is bordered by agricultural lands to the west, salt marsh communities to the north and south, and Delaware Bay to the east (figure 1-1). Figure 1-1. Bombay Hook National Wildlife Refuge

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SCOPE OF HABITAT MANAGEMENT PLAN A Habitat Management Plan (HMP) is a dynamic, working document that provides long-term (15-year) vision, specific guidance, continuity, and consistency for managing refuge habitats in accordance with the USFWS’s HMP policy (620 FW 1). Annual Habitat Work Plans (AWHPs) are annual work plans that provide specific guidance in support of HMPs. The lifespan of an HMP is 15 years and HMPs are reviewed every 5 years utilizing peer review recommendations, as appropriate, in the HMP revision. Reviews include the use of adaptive management to assess and modify management activities as research, monitoring, and priorities may require. Habitat inventory and monitoring essential to the HMP will be identified in accordance with the guidance provided in the Habitat and Wildlife Inventory and Monitoring chapter (701 FW 2) and documented in the refuge’s Inventory and Monitoring Plan (IMP). The Service is obligated to manage wildlife habitat at Bombay Hook NWR in accordance with an approved plan that, when implemented, will help achieve refuge purposes, fulfill the Refuge System mission, and comply with all applicable laws, regulations, and policies governing the management of System lands. The HMP guides future refuge management in accordance with current laws, regulations, policies, and practices employing the best available science and considerations for adaptive management. The HMP was developed in accordance with current guidance for selection of priority biological resources and habitats, as well as for writing biological goals, objectives, and strategies (Taylor and Paveglio 2017, Adamcik et al. 2004, Powell and Casey 2019). Combined, these efforts provided clarity about the desired future conditions we aim to protect, enhance, and/or restore on the refuge for the benefit of trust resources over the next 15 years. Appendix A of this HMP is the environmental assessment (EA) that evaluates the potential environmental effects associated with implementing this HMP (the proposed action). The EA complies with the National Environmental Policy Act of 1969 (NEPA; Public Law 91-190, 42 U.S.C. 4321 et seq.) in accordance with Council on Environmental Quality regulations (40 Code of Federal Regulations [CFR] 1500–1508) and U.S. Department of the Interior regulations and policies (Secretarial Order 3355; 43 CFR 46; 516 Departmental Manual 8; 550 FW 3). MISSION MANDATES 1.3.1 U.S. Fish and Wildlife Service The USFWS mission is to “work with others to conserve, protect, and enhance fish, wildlife, plants and their habitats for the continuing benefit of the American people,” and the USFWS functions as the primary Federal agency responsible for doing so. Specific responsibilities include enforcing Federal wildlife laws, managing migratory bird populations, restoring nationally significant fisheries, administering the Endangered Species Act, restoring wildlife habitat such as wetlands, and managing the Refuge System.

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National Wildlife Refuge System The mission of the Refuge System is to: Administer a national network of lands and waters for the conservation, management, and where Federal Trust Resources refer to the appropriate, restoration of the fish, wildlife, and USFWS's responsibilities, as charged plant resources and their habitats within the United by Congress to the Secretary of the States for the benefit of present and future Interior, for the conservation of fish and generations of Americans. wildlife. These responsibilities are defined by legislation, treaty, or similar The National Wildlife Refuge System Administration Act authority (e.g., Fish and Wildlife Act, (1966) as amended by the National Wildlife Refuge Endangered Species Act, Migratory Bird System Improvement Act (1997) (16 U.S.C. 668dd– Conservation Act). The duties to protect 668ee; Public Law 105-57; Improvement Act) defines the and steward interjurisdictional fisheries, Refuge System; directs the Secretary of the Interior to federally listed species, migratory birds, maintain the biological integrity, diversity, and and jurisdictional wetlands are shared environmental health (BIDEH) of the Refuge System; and with other Federal agencies and state governments, and the degree to which it authorizes the Secretary to permit any use of a refuge the Service is involved varies with provided such use is compatible with the major purposes species and situations. for which the refuge was established. The Improvement Act established the legitimacy and appropriateness of the six priority public uses (hunting, fishing, wildlife observation and photography, environmental education, and interpretation) and established a formal process for determining resource conservation and land use compatibility. Although public uses are allowed within the Refuge System, in order to fulfil primary habitat function and refuge designation mandates, it is often necessary that the USFWS establish closed areas or otherwise restrict activities that are in conflict with refuge establishment purposes and USFWS stewardship responsibilities for Federal trust resources. The Improvement Act offered a renewed vision for the Refuge System where: • Wildlife comes first.

• Refuges are cornerstones for biodiversity and ecosystem-level conservation.

• Lands and waters of the Refuge System are biologically healthy.

• Refuge lands reflect national and international leadership in habitat management and wildlife conservation. National wildlife refuges are established under a variety of authorities. The purposes of a refuge are specified in, or derived from, the law, proclamation, executive order, agreement, public land order, donation document, or administrative memorandum establishing, authorizing, or expanding a refuge, refuge unit, or refuge subunit. Coastal Delaware National Wildlife Refuge Complex Bombay Hook NWR was established by Executive Order 7643 in 1937 (2 CFR 1305), under authority of the Migratory Bird Conservation Act of 1929 (MBCA; 16 U.S.C. 715d). The primary purpose of the refuge is “…for use as an inviolate sanctuary, or for any other management purpose, for migratory birds.” Prime Hook NWR, approximately 25 miles south of Bombay Hook NWR, was established in 1963 under authority of the Migratory Bird Conservation Act as a satellite refuge of Bombay Hook NWR for use as an inviolate sanctuary, or any other management purpose, expressly for migratory birds. Prime Hook NWR became independently managed in 2000. However, in 2007 Prime Hook NWR and Bombay Hook

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NWR were reorganized as the Coastal Delaware NWR Complex. Although the same staff oversee both refuges, they are considered independent in terms of management purpose, goals, objectives, and strategies. Bombay Hook National Wildlife Refuge The refuge envisions Bombay Hook NWR’s conservation potential as described in this vision statement: The extensive tidal salt marshes at Bombay Hook National Wildlife Refuge are recognized as a critical resting, refueling, and breeding area for many bird species along the Atlantic flyway. Here birds find rest and nourishment during migration and also a haven in the winter. We will adapt to an ever-changing environment by building on native wildlife habitat diversity, with emphasis on developing late successional forests and restoring salt marsh habitats. A healthy refuge will provide opportunities for visitors to enjoy wildlife viewing and hunting in a natural setting. Educating about wildlife and the refuge’s unique heritage, and improving facilities will enhance the visitors experience while protecting the cultural integrity of the area. To achieve this, we will seek partnerships with other agencies, interest groups, landowners, and local communities. RELATIONSHIP TO OTHER PLANS AND GUIDANCE Federal Policies and Guidance The USFWS policies, orders, and other regulations that guide habitat management on refuges are compiled into the USFWS Manual (USFWS 2018). Several of these mandates, detailed below, are pertinent to the development of HMPs. In response to these mandates, the USFWS likewise has undertaken various strategic planning efforts, which are described in Section 1.4.3. Habitat Management Planning Policy – USFWS 620 FW 1 (2002) The Habitat Management Planning Policy applies to the development of refuge HMPs and Annual Habitat Work Plans (AHWP). The HMP policy and guidance describe strategies and implementation schedules for meeting goals and objectives, and thus direct the content and considerations addressed in this HMP. Biological Integrity, Diversity and Environmental Health Policy – USFWS 601 FW 3 (2001, with Amendment 1, 2006) The BIDEH Policy provides guidance for conservation and management of the broad spectrum of fish, wildlife, and habitat resources found on refuges and associated ecosystems by directing the maintenance and restoration, where appropriate. Further, it provides refuge managers with an evaluation process to analyze their refuge and recommend the best management direction to prevent further degradation of environmental conditions; and where appropriate and in concert with refuge purposes and Refuge System mission, restore lost or severely degraded components. The role of BIDEH is considered in habitat management planning at Bombay Hook NWR to the extent that it supports the refuge purpose, goals, and objectives. Inventory and Monitoring Policy – USFWS 701 FW 2 (2014) The USFWS Inventory and Monitoring Policy provides guidance for developing an IMP for a refuge, typically produced following the completion of the HMP. The IMP describes priorities for natural resource surveys, the selection, and design of survey protocols, data storage and analysis, and reporting results. It accommodates all levels of natural resource surveys from the refuge level to participation in landscape, regional, national, and international inventory and monitoring programs, both internal and external to the USFWS. Overall, this policy promotes consistency in the planning and implementation of inventory and monitoring throughout the Refuge System. U.S. Department of the Interior Adaptive Management Guide (Williams et al. 2009)

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Adaptive management principles were employed in the development of this HMP, and adaptive management strategies will continue to be used at the Bombay Hook NWR to respond to changing conditions and the dynamic nature of the ecosystem that may impair the ability to measure and achieve set habitat objectives. Although aspects of the U.S. Department of the Interior Adaptive Management Guide were considered throughout the HMP development process, USFWS policy for development of HMPs (e.g., 620 FW 1, 601 FW 3, 701 FW 2) was the overarching direction used to complete this HMP. USFWS Strategic Plan for Responding to Accelerating Climate Change (2010) The USFWS Strategic Plan for Responding to Accelerating Climate Change (2010) provides guidance for the consideration of actual and projected climate change impacts to fish and wildlife populations and their habitats in USFWS planning, decision making, consultation and evaluation, management, and restoration efforts Multi-stakeholder Conservation Initiatives and Regional Plans Refuge efforts have a greater potential of success when combined with activities and partnerships across the larger conservation network. In addition to USFWS policies and other mandates, further guidance for wildlife habitat management at Bombay Hook NWR is provided by several international, national, and regional plans. Many landscape-scale wildlife conservation plans and initiatives overlap and compliment the mission and vision of the refuge–these plans often have a different emphasis and geographic scope, but also can share common focal species, ecosystem traits, partners, or purposes. As a partner in many wildlife- or habitat-focused initiatives, the USFWS strives to incorporate relevant programs and to support existing progress to the extent practicable (Table 1-1). These plans or initiatives have produced species of concern data sets that are evaluated in Chapter 3 as part of the development and prioritization of refuge-specific resources of concern (ROC).

Table 1-1. Plans Consulted During Bombay Hook NWR HMP Process Planning Plan Region Website

U.S. Fish and Wildlife Service (USFWS) Special Status Species Lists

USFWS Northeast Region Fish and Aquatic USFWS Region https://www.fws.gov/northeast/fisheries/ Conservation Priority Species (USFWS 2018) 5

USFWS Landscape Conservation Cooperative (LCC) http://www.naturesnetwork.org/ Nature’s Network

• North Atlantic LCC Regional Species of http://northatlanticlcc.org/resources/state-wildlife- Greatest Conservation Need (RSGCN) action-plans/2015-northeast-regional-conservation- North Atlantic synthesis/index_html LCC • North Atlantic LCC Representative Species http://northatlanticlcc.org/products/landscape- capability-for-representative-species

• North Atlantic LCC Rare Plants http://northatlanticlcc.org/products/prioritizing-plant- species-for-conservation

USFWS At-Risk Species National https://www.fws.gov/at-risk/

Federal Threatened and Endangered Species https://www.fws.gov/endangered/ (February 2015) National https://ecos.fws.gov/ecp0/reports/species-listed-by- state-report?state=DE&status=listed

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Table 1-1. Plans Consulted During Bombay Hook NWR HMP Process Planning Plan Region Website

Multi-stakeholder Conservation Initiatives and Special Status Species Lists

North American Bird Conservation Initiative http://nabci-us.org/ (NABCI) Implementation Plan for Bird Conservation BCR 30: Region (BCR) 30 Southern New England/Mid- Southern New Atlantic (Steinkamp 2008). England/Mid- Atlantic Region http://www.acjv.org/BCR_30/BCR30_June_23_2008 _final.pdf

• NABCI State of North America’s Birds, http://www.stateofthebirds.org/2016/resources/specie Species Assessment Summary and Watch National s-assessments/ List (2016)

Partners in Flight Landbird Conservation Plan BCR 30 https://www.partnersinflight.org/resources/the-plan/ (Rosenberg et al. 2016)

• Bird Conservation Plan for the Mid-Atlantic Physio-graphic https://www.partnersinflight.org/resources/pif-bird- Coastal Plain Physiographic Area (Watts Area 44: Mid conservation-plan-the-mid-atlantic-coastal-plain- 1999) Atlantic Coastal physiographic-area-44/ Region

North American Waterfowl Management Plan https://nawmp.org/ (Ringleman et al. 2012a) and Action Plan (Ringleman https://nawmp.org/documents?field_document_type_ et al. 2012b) target_id=34

• North American Waterfowl Management http://acjv.org/planning/waterfowl-implementation- Plan - Atlantic Coast Joint Venture plan/ Waterfowl Implementation Plan (2005) Atlantic Coast • Saltmarsh Habitat and Aviation Research Joint Venture https://www.tidalmarshbirds.net/ Program (SHARP)

• North American Waterfowl Management http://blackduck.cmi.vt.edu/docs/BDJV%20Strategic Plan - Black Duck Joint Venture Strategic %20Plan%202008_2013.pdf Plan, 2008-2013 (Black Duck Joint Venture Management Board 2008)

• Black Rail http://acjv.org/

• Saltmarsh Sparrow http://acjv.org/saltmarsh-sparrow-2/

Northeast Partners in Amphibian and Reptile http://northeastparc.org/northeast-species/ Conservation (NEPARC), Northeast Amphibian and Reptile Conservation Species of Regional USFWS Region Responsibility and Conservation Concern (2018; 5 http://www.northeastparc.org/products/pdfs/NEPAR 2010) C_NEspeciesofresponsibility.pdf

The Xerces Society for Invertebrate Conservation https://xerces.org/ National https://xerces.org/red-lists/

State Plans and Special Status Species Lists Delaware Wildlife Action Plan (Delaware Division of http://www.dnrec.delaware.gov/fw/dwap/Pages/WAP Natural Resources and Environmental Control, Delaware -Progress.aspx Division of Fish and Wildlife [DNREC DFW] 2015)

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Table 1-1. Plans Consulted During Bombay Hook NWR HMP Process Planning Plan Region Website

http://www.dnrec.delaware.gov/fw/NHESP/informati • Delaware’s Endangered Species (DNREC on/Pages/Endangered.aspx DFW 2015)

Refuge-specific Lists Lists of birds (USFWS, undated), mammals (USFWS Refuge https://www.fws.gov/refuge/Bombay_Hook/visit/bro undated), amphibians and reptiles (USFWS undated), chures.html fish (Johnson-Pohlman and Hewes 1995), invertebrates (USFWS undated), trees (Holgersen and McAvoy 1999), wildflowers (Holgersen 1995) BCR = Bird Conservation Region; DNREC DFW = Delaware Division of Natural Resources and Environmental Control, Division of Fish and Wildlife; LCC = Landscape Conservation Cooperative; NABCI = North American Bird Conservation Initiative; NEPARC = Northeast Partners in Amphibian and Reptile Conservation; SHARP= Saltmarsh Habitat and Aviation Research Program; USFWS = U.S. Fish and Wildlife Service

Bombay Hook National Wildlife Refuge-Specific Plans Refuge management decisions are guided by previously approved management plans, including: • Bombay Hook NWR Marsh and Water Management Plan (1994): The Marsh and Water Management Plan provides refuge managers with a marsh and water management framework that outlines maintenance, rehabilitation, and water level management covering a period of 5 to 10 years. Currently, management of the four larger impoundments (Bear Swamp, Raymond, Shearness, and Finis) largely follows guidance outlined in this plan. Additional smaller pools and moist soil units addressed in the plan have not been actively managed in recent years due to problems with the water management infrastructure and loss of maintenance staff. Tidal marsh habitat is briefly described in the plan. Management activities including limited burning, public hunting and trapping, and mosquito control are mentioned, but not discussed in enough detail to provide meaningful guidance.

• Bombay Hook NWR Cropland Management Plan (1996): The Cropland Management Plan provides refuge managers with a cropland and grassland management framework to provide food and cover for waterfowl and other refuge resources, but primarily focusing on a cooperative farming program. The limited guidance on grassland management is still generally followed, but this plan was rendered obsolete in 2010 when the refuge stopped cooperative farming.

• Bombay Hook NWR Forest Management Plan (1988): The Forest Management Plan provides refuge managers with a summary of the location and condition of forest stands, grouped into compartments, and outlines management prescriptions for each compartment. The limited forest management activities prescribed, such as evaluating stands for commercial harvest and experimental reintroduction of Atlantic white cedar, have not been implemented.

• Bombay Hook NWR Fire Management Plan (2008)/Prescribed Burn Plans (revised annually): Each refuge in the NWRS containing “vegetation capable of sustaining fire” is required to prepare a Fire Management Plan as mandated by USFWS policy. A Fire Management Plan addresses wildland and prescribed fire events with guidelines on the level of protection needed to

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ensure safety, protect facilities and resources, and restore and perpetuate natural processes. Prescribed fire, which is used to mimic natural processes and manage certain habitats, has been incorporated as a management strategy into this HMP as possible. Annual Prescribed Burn Plans are tiered from the Bombay Hook NWR Fire Management Plan. Objectives for each habitat type are dependent on the Marsh and Water Management Plan, the Forest Management Plan, and the Cropland Management Plan, described above.

• Bombay Hook NWR Hunt Plan (1992): The Hunt Management Plan provides guidelines for the administration of hunting activity and for the development, maintenance, and enforcement of regulations and guidelines on Bombay Hook NWR. It specifically addresses the areas of information, access, use patterns, regulations, area restrictions, permits, and enforcement. It sets forth a plan for public hunting on the refuge as a form of wildlife oriented recreation and in some cases as a wildlife management tool. Hunting programs include big game (i.e., white-tailed deer), upland game birds, small game, waterfowl, and other migratory game birds. The refuge does not maintain a separate Spill Prevention, Control, and Countermeasures (SPCC) Plan or Integrated Pest Management (IPM) Plans. However, integrated best management practices for invasive pests are incorporated into planning and management strategies.

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Figure 1-2. Using the Habitat Management Plan for Annual Habitat Work Planning

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Wetland on Wildlfe Drive

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CHAPTER 2. EXISTING CONDITIONS This section summarizes pertinent background information that is required for context of the HMP rationale, including a description of existing conditions such as physical environment (water quality, topography and soils, geology and hydrology, climate, and air quality); the biological environment (terrestrial, wetland, aquatic habitats, and fish and wildlife); the socioeconomic environment (geographic setting, history and archaeology, land use, and recreational use); historic and current ecosystem influences; and current threats. This analysis is not encyclopedic, and information is streamlined with intent to help inform the development of appropriate future management actions. LANDSCAPE SETTING Bombay Hook NWR is located in Kent County, Delaware, situated along approximately 9 miles of the western shore of the Delaware Bay (Figure 1-1; Figure 2-1). The refuge currently encompasses 16,162 acres, with an additional 4,566 acres approved within the acquisition boundary. The refuge headquarters and visitor center are located approximately 11 miles from Dover, the State capital of Delaware, and about 8 miles from the town of Smyrna, Delaware. The Delaware Bay is an important migratory stopover and wintering area for both waterfowl and shorebirds in the Atlantic Flyway. In particular, the bay is considered a major shorebird migration stopover and staging site where birds feed on the plentiful eggs of spawning horseshoe crabs. Bombay Hook NWR is in Bird Conservation Region (BCR) 30, the Partners in Flight (PIF) Physiographic Region 44, and within the Western Hemispheric Shorebird Reserve Network (1986). It was named a Ramsar Wetland Site of International Importance (1992) and an Audubon Society Important Bird Area of the Delaware Bay (2000). Table 1-1 identifies the refuge’s relationship to the various partnership planning groups that overlap refuge mission and geography. The refuge is primarily coastal salt marsh habitat, and north and south of the refuge are additional expanses of salt marsh in private, state, or non-profit ownership. Lands inland of the refuge are dominated by row crop agriculture interspersed with low-density housing. As defined by the North Atlantic Landscape Conservation Cooperative (NALCC 2017), Bombay Hook NWR is a regionally crucial core habitat, connected through various natural corridors to other core habitats according to Nature’s Network Conservation Design (NALCC 2017) (Figure 2-2). Additional protected lands in the area include: • Prime Hook NWR (approximately 10,000 acres), located 25 miles south of Bombay Hook NWR. • Prime Hook Wildlife Management Area (WMA) (698 acres), adjacent to Prime Hook NWR to the south. • Little Creek WMA (4,721 acres), adjacent to Bombay Hook NWR to the south, above Port Mahon. • Ted Harvey Conservation Area (2,661 acres), 15 miles south of Bombay Hook NWR, above Bower’s Beach. Bombay Hook NWR and Prime Hook NWR share administrative resources (such as personnel and equipment) and are collectively managed as the Coastal Delaware NWR Complex. Each refuge is managed separately, in accordance with its designated refuge purpose(s) and unique attributes.

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Figure 2-1 Refuge Location Relative to Delaware Bay Region NWRs

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Figure 2-2. Natural Areas and Corridors in Vicinity of Bombay Hook NWR

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LAND MANAGEMENT HISTORY Figure 2-3 illustrates a brief timeline of Bombay Hook NWR history Figure 2-3. Bombay Hook NWR History •1679 - sale of marshland by Mechacksett, Chief of the Kahansink Indians, to Peter Bayard of New York. Known to the Native Americans as Canaresse, meaning “shaggy bushes” or “thicket". The name Bombay Hook evolved from the Dutch name “Bompies Hoeck” meaning “little-tree point.” •1682 - A canal was built between Delaware Bay and Smyrna. This created waterway became the Smyrna River. •1680's - Dutch settlers cut salt hay from the marsh, trapped muskrats and hunted waterfowl. The tidal streams that interlace the marsh provided fish, crabs and oysters. Pre-Refuge •1753 - The Allee House was built by Abraham Allee, a Hugenot refugee from Artois, Establishment France. •1848 - A hotel was built at Bombay Hook Island as the area had become a popular tourist resort. •1878 - A severe storm referred to by local residents as the "great tidal-wave" destroyed summer resorts on Collins and Fraland Beach. The storm changed the landscape of Bombay Hook. Prior to 1878, the inner marshes were protected from storms and high tides by the dunes and banks fronting the bay. These dunes were breached by the storm and were never repaired, and are still gone today. •1920s to 1930s - 4 to 5 million Horseshoe crabs were harvested from Delaware Bay.

•1937 - First refuge lands were purchased with Duck Stamp funds to allow for a resting and feeding area for migratory and wintering waterfowl. •1938 to 1942 - An African American company of the Civilian Conservation Corps (CCC) completed construction projects to establish the new migratory waterfowl refuge at Bombay Hook. They built a dike and water control structures creating Raymond Pool, enclosed Shearness Pool and Finis Pool. They cleared timber and undergrowth from Shearness and Finis swamps., planted 50,000 tree seedlings, dug mosquito control Early Refuge ditches, plus other projects still evident today. History •1942 to 1945 - Army Air Corps, based at Dover, used parts of the refuge for training with air-to-ground rockets. •1961 - The fourth freshwater impoundment, Bear Swamp Pool, was added, making a total of 1,100 acres of freshwater impoundment. •1980 - An Atlantic Beaked Whale beached at Bombay Hook. •1986 - Bombay Hook NWR represented the US in "World Safari" a satellite program by National Geographic, BBC, and Turner Broadcasting. Bombay Hook NWR was selected because of its high concentration of snow geese.

•1997 - Congress authorizes the Refuge Improvement Act, which directs the Secretary of the Interior to maintain the biological integrity, diversity, and environmental health (BIDEH) of the NWRS; and it authorizes the Secretary to permit any use of a refuge provided such use is compatible with the major purposes for which the refuge was Post Refuge established. Improvement •2012 - Superstorm Sandy poured over 11 inches of rain across Delaware and caused Act History billions of dollars of damage to infrastructure across the Mid-Atlantic. Although Bombay Hook NWR was relatively unaffected by the storm, other refuges and habitats in the region experienced wide-scale damage. •2015 - Bombay Hook NWR was featured on the fourth 2015 release of the America the Beautiful Quarters series minted by the U.S. Treasury.

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Pre-Refuge Land Use Prior to European settlement, upper Delaware was dominated by hardwood forest and coastal wetlands. Settlements arrived in areas where transportation was available, and communities chiefly occurred along waterways and on the “necks,” or peninsulas of higher ground, adjacent to marshes. By 1685, most of the land in the area in the region was farmed, and tobacco dominated as the prime commodity. Other crops such as corn, rye, barley, and wheat were also grown, but had lesser influence until the mid-1700s as transportation and storage innovations increased the reach of the regional market. This growth dynamic was further pronounced after Dover was established as the capital city of Delaware in 1777, and the trend continued as roads and automobiles became increasingly reliable forms of transportation. To facilitate access to the rich, alluvial soil of the coastal area, ditches and dikes were installed to make marshlands accessible as meadow for grazing livestock. In the early 19th century, agribusiness further focused on marsh drainage to further expose rich, fertile soils for crop production. Wealthy landowners came together to form ditch corporations that would petition state legislature for the rights and taxable support of large-scale reclamation projects; although, despite substantial investment, these ditch corporations were rarely more than marginally successful. Extensive infrastructure was required to effectively drain a marsh; including the installation of earthen embankments that often measured 6 to 8 feet high, 12 feet wide at their base, and 3 feet wide at their summit to maintain a minimum 3-foot crest above average high tide. After an embankment was established around a marsh, a network of canal channels were dug to drain it. The smallest of these hand dug ditches were often little more than 3 feet deep and 9 feet wide, but typically fed into larger central channels that could be as deep as 5 feet and up to 20 feet wide. The larger channels drained the marshes through sluices that penetrated the embankments. Natural forces, including muskrats and storms, required exhaustive attention to, and maintenance of, these systems. In 1878, a Class 1 hurricane swept through Delaware Bay and 10 feet of storm surge overtopped all land reclamation efforts, effectively rearranging the land at (what is now) the refuge; this event diminished the attractiveness of maintaining private farming enterprise in the area. Muskrat trapping and waterfowl hunting followed as the primary uses of the land, with ditching for mosquito control the major activity upon the landscape. USFWS Stewardship Civilian Conservation Corps The Civilian Conservation Corps (CCC) Early Management Company 3269–C was established on the newly created Bombay Hook NWR in 1937 with the explicit purpose of creating a migratory waterfowl refuge. Until the group was reassigned 4 years later, their primary task was mosquito control, which began with the mission to drain the marshes through cutting “parallel ditches” (Figure 2-3). Parallel ditches were each 10 to 20 inches wide, up to 30 inches deep, spaced 150 feet apart through the marsh, and drained into a gut (i.e. ditched channel) or tidal stream. The ditches were dug by a two-man team, one using a long, heavy spade, and the other using a hook. Sixty- to 80-pound clumps of marsh sod were removed at a time, and a two-man team could cut an average of 235 feet of ditch a day. Despite the effort, parallel ditches were only completed on a portion of (what is now) the refuge as a new theory of biological control emerged. In 1938, mosquito control tactics evolved to employ dynamite to blast craters that would create permanent pools supporting year-round habitat for mosquito larvae-eating fish (Figure 2-4). The CCC also constructed various buildings and other infrastructure for the refuge and performed extensive clearing efforts with intent to create freshwater impoundments for waterfowl. This work was problematic due to the difficulty moving people and equipment through the unconsolidated wetland muck. By the time the CCC enrollees left in 1942, only a portion of the swampland was cleared, primarily at Shearness, while most of the clearing at Finis was limited to the more accessible edges.

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Figure 2-5 compiles known records of various wetland management actions at Bombay Hook NWR. The effects of some of these actions are still evident on the landscape and continue to shape the ecosystems and management capabilities present on the refuge. Some of these historic alterations were documented by archeological studies and some have been observed by studying historic imagery and reviewing annual narratives, deeds, and other public records.

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Figure 2-4. Legacy of Wetland Management Activities on Bombay Hook NWR (Ditching, clearing, impoundment management, pothole blasting)

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Post-CCC (1943) to Present Although land management techniques evolved over the next 80 years, refuge management maintained its focus on sustaining the core mission to support bird populations, with mosquito control, farming, hunting, and other recreation as secondary activities. Controlled burning was extensively used as a management technique throughout the refuge, and concerns about keeping fire events within the refuge boundary led to the construction of a 1.5-mile firebreak on the northern boundary from Duck Creek to the Delaware Bay shoreline. The firebreak consists of two parallel ditches with circulating water, 150 feet apart, with the center strip cleared of all brush and grass. Refuge managers also installed and maintained water-control structures and dikes and performed dredging in various locations. Prior to the mid-1980s, water level management traditionally included maintaining relatively high water levels during the growing season. However, the high water levels and associated carp populations reduced growth of aquatic vegetation and reduced the value of the impoundments to waterfowl and presumably shorebirds. In the mid-1980’s, management objectives and regimes for the impoundments were altered to include drawdowns that would promote annual vegetation growth. The salt marsh was cropped for salt hay until 1945, including annual spring controlled burning. In upland areas of the refuge, eventually over 800 to 1,000 acres were farmed for both cash commodity crops as well as food plots, which included plowing and seeding for corn, soybeans, wheat, and small patches of buckwheat and rye. Cooperative farming was discontinued in 2010. For the most part, the fields were not actively or gradually transitioned to a natural state; thus, these fields have extensive populations of invasive species, particularly Canada thistle (Cirsium arvense), and are difficult to maintain in an early successional state. The refuge has a large wildlife and recreational development component, and management historically also focused on grasslands management, native plantings, and invasive control specific to mute swans (Cygnus olor) and invasive plants. In addition, two areas of the refuge were acquired from the U.S. Air Force that were used as bombing ranges. Remedial actions were undertaken between 1992 and 2006, and site monitoring is ongoing through 2036 (http://shorturl.at/fCDQ3, accessed August 2019). The most recently completed review concluded that “response actions at the site are in accordance with the remedy selected by Environmental Protection Agency (EPA) and that the remedy continues to be protective of human health and the environment in the short term” (http://shorturl.at/dqxEX, accessed August 2019). Upland management was largely focused on game species. Waterfowl, fur bearers, white-tailed deer (Odoceoileus virginianus), mourning dove (Zenaida macroura) and American woodcock (Scolopax minor) estimates were reported, as well as nest predators such as red fox (Vulpes vulpes) and northern raccoon (Procyon lotor). Land was cleared and planted to support nesting, migrating and wintering waterfowl. Food strips were planted to millet, sorghum, buckwheat, and smartweed. Eastern cottontail (Sylvilagus floridanus) were live trapped and transplanted to State management areas. There was an extensive winter and spring feeding program. In addition to spreading feed for waterfowl, upland game were given mixtures of wheat, corn, soybeans, barely, and buckwheat. Unfortunately, plants that would later prove to be invasive were planted including sericea lespedeza (Lespedeza cuneata) and autumn olive (Elaeagnus umbellata). Forested or brushy areas and fence rows were cleared. Some wood was sold for firewood; some was cut to build corduroy roads on the saltmarsh to facilitate movement of heavy equipment during dike construction, and some was milled into boards for building construction. The herbicides 2, 4-D and 2, 4, 5-T were used to clear hardwood swamp growth in the impoundments. Some pasture was maintained on refuge for cattle and green browse for waterfowl. Not all crops were intended for wildlife consumption. Farming was conducted by refuge personnel and share croppers. Some crops were harvested for planting or baiting/banding elsewhere as there was an

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extensive exchange program between refuges. At one time, refuge staffing included as many as five individuals tasked with maintenance and habitat management, dominated largely by cultivation of agricultural crops, but eventually staffing/funding shortages forced a change. Some areas were taken out of agricultural production, as they were less productive and difficult to work and an extensive drainage system was constructed, particularly on Dutch Neck where about 9 miles of ditches of varying size were installed. In the early 1960’s the refuge moved away from force account farming operations to a cooperative system where farmers planted a cash crop that they harvested and sold. In return, the farmers provided a service (generally planting cover crops) valued at the local rental price for farmland. The refuge at one time managed a maximum of approximately 1,100 acres in a rotation of row crops and green browse. Cooperative farming continued until 2010. Many of these fields have since been managed periodically, as staffing and resources allowed, to maintain an early successional condition while future habitat management planning was evaluated. In recent decades, management of the large impoundments on the refuge has continued in much the same way, utilizing drawdowns to provide mudflats for migrating shorebirds and to promote vegetation for migrating waterfowl. However, smaller impoundments and moist soil units that were constructed in the 1990’s have not been actively managed, due to reduction in staffing, difficulty with access as surrounding habitat has changed, and infrastructure falling into disrepair. There has not been active management of the refuge forests, as management emphasis has been on upland fields and managed wetlands. Table 2-1 summarizes most land uses and habitat alterations that have occurred on the refuge, particularly in marsh and open water areas. Table 2-1. Past Management Actions at Bombay Hook NWR Management Action Management Intent Prior to FWS Dugouts Watering livestock

Road Construction (short private roads and causeway to Woodland Access Beach)

Channelization Major navigation

Disking/Plowing Crops

Diking/Impounding “Macro Units” (drainage or maintenance of Production of hay or cultivated crops low water levels

Grazing Livestock

Compaction Livestock and machinery

Rutting Substrate Livestock and machinery

Prior To and During FWS Management Diking/Impounding “Micro Units” (drainage or maintenance of Mosquito control and wildlife habitat high water levels)

Building Construction (Cabins and Ferry Facilities) Access

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Table 2-1. Past Management Actions at Bombay Hook NWR Management Action Management Intent Parallel and Radial Ditching Mosquito control

Mowing (without impounding) Haying

Burning (routine burning ceased approx. 1960) Hay farm management and invasive plant control

Water Control Structures and Earthen Ditch Plugs Water level control on natural and excavated guts on the open non-diked marsh

USFWS Management Blasted Potholes Mosquito control and wildlife (waterfowl) habitat

Open Marsh Water Management Mosquito control and wildlife

Diking/Impounding “Macro Units” (drainage or maintenance of Wildlife habitat high water levels)

Well Drilling and Water Extraction (artesian well/) – During Salt marsh salinity management USFWS mgt.

Munitions Range (U.S. Army Air Force, 1940s) Military Target and Testing

CLIMATE The climate at Bombay Hook NWR is characterized by warm, humid summers with frequent thunderstorms and cold winters with snowfall (Wurster et al. 2013). The refuge receives a monthly average of approximately 3.71 inches of rain, which is typically evenly distributed throughout the year. Temperatures range from an average minimum of 25 °F (-3.9 °C) in January to an average maximum of 87.4 °F (30.8 °C) in July. AIR QUALITY The Clean Air Act provides the principal framework for national, state, and local efforts to protect air quality. In accordance with the Clean Air Act, National Ambient Air Quality Standards have been established by the EPA and Delaware Division of Natural Resources (DNREC). Criteria pollutants include particulate matter, carbon monoxide, sulfur dioxide, nitrogen oxides, lead, and ozone. In general, air quality in Kent County is good and is currently in attainment for all air quality standards. GENERAL DESCRIPTION OF VEGETATIVE COMMUNITIES Development of this HMP is largely centered on the habitats as observed at the refuge, and for purposes of this HMP, vegetative communities may be lumped together, especially when habitat goals overlap or require similar management actions. These observed habitats correspond to and are defined in the Delaware Wildlife Action Plan (DE WAP; DNREC 2015), and Table 2-2 provides a crosswalk between the habitats observed at the refuge and the nomenclature in the DE WAP. Fine-scale vegetation community mapping was conducted at the refuge in 2007-2008 (Coxe 2008) in accordance with the National Vegetation Classification System (NVCS; USNVC 2017), and habitat mapping associated with

2.0 Existing Conditions 2-20 August 2020 Habitat Management Plan for Bombay Hook National Wildlife Refuge the DE WAP occurred as a separate effort in 2015. Full descriptions of these habitats and their associated ROC species are found in Chapter 3. Bombay Hook NWR consists of coastal, forested, freshwater, and grassland and shrubland habitats. Approximately 77 percent of the refuge is tidal salt marsh, with the remaining uplands currently maintained as shrubland, grassland, and forests (Table 2-3). The existing habitat conditions for Bombay Hook NWR are depicted in Figures 2-5 through 2-7 below.

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Figure 2-5. Existing Habitat Conditions for Bombay Hook NWR Overview

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Figure 2-6. Existing Habitat Conditions for Bombay Hook NWR North

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Figure 2-7. Existing Habitat Conditions for Bombay Hook NWR South

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Table 2-2. Nomenclature of Habitats Observed on Bombay Hook NWR HMP Broad NVCS Community DE WAP Habitats Habitat Types (Coxe 2008) (DNREC 2015) Coastal Habitats Atlantic Big Cordgrass Marsh Brackish Tidal Marsh and Shrubland

Estuarine Coastal Mesohaline Water NA*

Estuarine Coastal Polyhaline Water NA

Irregularly Flooded Eastern Tidal Salt Tidal Salt Marsh Tidal High Salt Marsh Shrub

North Atlantic High Salt Marsh Tidal High Salt Marsh

North Atlantic Low Salt Marsh Tidal Low Salt Marsh

Reed Tidal Marsh Reed Tidal Marsh

Beach Sandy Beach Beach Overwash Dune Grassland Maritime Dune and Grassland

Forested Habitats Mid-Atlantic Mesic Mixed Hardwood Mesic Mixed Hardwood Forest Forest

Northeastern Dry Oak-Hickory Forest Piedmont Oak Forest

Upland Forest Northeastern Modified Successional Modified/Successional Forest Forest

Successional Sweetgum Forest Modified/Successional Forest

Successional Tuliptree Forest Basic Mesic Forest

Chesapeake Bay Non-riverine Wet Coastal Plain Flatwood and Depression Hardwood Forest Swamp

Red Maple-Gum Successional Swamp Coastal Plain Flatwood and Depression Forest Swamp

Red Maple-Seaside Alder Woodland Freshwater Shrub Swamp Forested Wetland Coastal Plain Flatwood and Depression Red Maple-Sweetgum Swamp Swamp

Successional Maritime Forest Maritime Forest

Coastal Plain Flatwood and Depression Swamp-loosestrife Shrub Swamp Swamp

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Table 2-2. Nomenclature of Habitats Observed on Bombay Hook NWR HMP Broad NVCS Community DE WAP Habitats Habitat Types (Coxe 2008) (DNREC 2015) Freshwater Habitats

Seasonally-managed Impoundment Impoundment Freshwater Impoundments Semi-permanent Impoundment Impoundment

Duckweed Vegetation NA

Eastern Cattail Marsh Emergent Freshwater Marsh Semi-permanent Freshwater Wetland Eastern Reed Marsh Emergent Freshwater Marsh

Farm Pond/Artificial Pond NA

Grassland and Shrubland Habitats Agricultural Field NA Early Successional Northeastern Old Field Early Successional Herbaceous Upland Northeastern Successional Shrubland Early Successional Shrubland * NA = Not Applicable; Not all NVCS communities from the 2008 mapping effort were recognized as distinct habitat types in the DE WAP (DNREC 2015), but were assigned appropriate broad habitat types for mapping purposes

Table 2-3. Summary of Current Refuge HMP Broad Habitat Types* Broad Habitat Type Acreage Total Land Cover Tidal Salt Marsh 12,800 79.6%

Upland Forest 900 5.6%

Forested Wetland 790 4.9%

Seasonally-managed Freshwater Impoundments 665 4.1%

Early Successional Upland 595 3.7%

Semi-permanent Freshwater Wetland 300 1.9%

Beach 30 0.2%

TOTAL 16,080 100 * Acreage derived from the 2008 refuge land cover data (Coxe 2008), cross-referenced to the community types in the DE WAP (DNREC 2015), and further refined by refuge staff utilizing spatial data during preparation of this HMP. Acreages are estimated from GIS and should not be used for legal purposes. Coastal Habitats Vegetation composition and structure within these communities is influenced greatly by water level in the Delaware Bay and to some extent by storms and shifting sand.

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• Tidal Salt Marsh. Salt marshes are dominated by two grass species, smooth cordgrass (Spartina alterniflora) and salt meadow cordgrass (Spartina patens), and often classified as “low marsh” or “high marsh” based on the interaction between hydrology and elevation, and the resulting plant communities. In higher elevation areas of the salt marsh, tidal shrublands dominated by high-tide bush (Iva futescens) or groundselbush (Baccharis halimifolia) occur. The refuge’s expansive salt marshes (approximately 12,800 acres) are not actively “managed.” Refuge staff conduct routine research and monitoring activities throughout the marsh to track the integrity of the habitat and status of its wildlife. The refuge has lost approximately 2000 acres (860 ha) of tidal marsh since 1961, with much of that loss coming in the marsh interior (McDowell 2017). Numerous factors have contributed to the loss of interior marsh, which the refuge may address in the future through restoration. Salt marsh restoration includes thin layer deposition, hydrological improvements, and common reed (Phragmites australis) control. Human intervention in the refuge’s tidal marshes over the past 300 years has resulted in extensive “legacy” impacts to the topography, hydrology, and ecosystem function at the refuge. Major impounding, dredging, and road building events, coupled with natural storm/tidal events and herbivory, continue to shape the evolution and influence the communities within Bombay Hook NWR. Despite these effects, the salt marshes at Bombay Hook NWR are among the largest expanses of relatively unaltered tidal marsh in the northeast.

• Beach. Bombay Hook NWR has about 30 acres of beach and dune habitat, which occurs as small pockets of sand over peat, sometimes referred to as “pocket beaches.” This beach habitat is considered in conjunction with the salt marsh, as part of the larger coastal habitat complex. This habitat is dynamic, and historic imagery indicates that large areas of marsh and beach at the shoreline have been lost from erosion, especially in the southern portion of the refuge. Forested Habitats Forested habitat is exceptionally valuable habitat in the region and is underrepresented in the current landscape. In addition to being described in the refuge vegetation mapping report (Coxe 2008), the refuge forests and woodlands were inventoried by the Delaware Forest Service in 2011 (Seybold 2011) in order to provide general forest management recommendations. The structure and species composition of each stand sampled (as of 2010-2011) is described in further detail in their report (Seybold 2011). The refuge contains approximately 1,690 acres of woodlands; however, most stands are severely fragmented and over half are less than 10 acres in size, particularly the upland forest. Refuge forests and woodlands occur mainly along the west edge of the salt marshes and pools along the west bank of the Delaware Bay. Some of the woodlands are also found along tidal and non-tidal stream bottoms that are feeding into the salt marshes. Some of the forested habitat occurs as very young forest in previously farmed fields. There is a wide variety of woodlands, including well-drained upland forest, ponded wetlands, wooded stream bottoms, very mature forests, and very early successional young woodlands. Twenty-four species of trees were identified on the survey, and at least 31 species of shrubs, vines, and invasive species. Across all sampled refuge woodlands and forests, there was an average of 0.56 super canopy trees (trees standing notably taller than the surrounding trees) per acre, 4.0 live tree cavities per acre, and 17.1 snags per acre. Currently, forests on the refuge are not actively managed, aside from limited invasive species control in some areas. In addition, public deer hunting on the refuge serves also as a population reduction strategy which helps limit adverse herbivory impacts on the forest. • Upland Forest. On the refuge, approximately 900 acres of existing upland forests consist of several different oak (Quercus spp.), mixed hardwood, and successional forest types. Dominant overstory species include red maple (Acer rubrum), sweetgum (Liquidambar styraciflua), tuliptree (Liriodendron tulipifera), white oak (Quercus alba), red oak (Quercus rubra), black oak (Quercus velutina), and some loblolly pine (Pinus taeda) and Virginia pine (Pinus virginiana).

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Understory species include black cherry (Prunus serotina), American holly (Ilex opaca), spicebush (Lindera benzoin), dogwood (Cornus spp), and blueberry (Vaccinium spp).

• Forested Wetlands. On the refuge, approximately 790 acres of existing forested wetlands consist mostly of Coastal Plain Flatwood and Depression Swamps and a smaller amount of Maritime Forest that occurs on the edges of salt marshes and areas that are exposed to brackish water inundation during storm tides. Dominant overstory species include red maple, sweetgum, and black cherry. Freshwater Habitats Seasonally managed Freshwater Impoundments: The refuge manages about 665 acres of impounded freshwater pools, including three large impoundments formed by diking the tidal marsh (Shearness, Raymond, and Finis), one impoundment upstream of Shearness Pool encompassing shrub-scrub and maple swamp (Bear Swamp), and several small moist soil units. The existing Marsh and Water Management Plan (USFWS 1994) describes the overall objectives for each impoundment. The most common management regime for these impoundments has been a slow spring drawdown to provide mudflats for migrating shorebirds, maintenance of lower water levels for plant germination through the summer, and a gradual re-flooding in the fall to give dabbling ducks access to the seeds of the wetland plants. The entire impoundment complex is reliant on precipitation and associated surface run-off as a primary water source, along with groundwater discharge. In situations with sufficient water levels, water can be moved into Shearness from neighboring Finis Pool and from Shearness Pool to Raymond Pool. Bear Swamp is totally dependent on rainfall within its very limited watershed. All three impoundments rely primarily on late summer and fall rain, which can result in a delay of planned re-flooding when precipitation is substantially below normal.

• Raymond Pool (63 acres) was formed in 1939 and is the oldest impoundment at Bombay Hook NWR. At full pool, a large portion of the impoundment remains open water. The impoundment is adjacent to tidal salt marsh to the south and east, and is connected to Shearness Pool by the Raymond-Shearness canal to the north. The dike separating the impoundment from the tidal salt marsh serves as a portion of the wildlife drive open to the public, and vegetation at Raymond Pool typically includes fall panic grass (Panicum dichotomiflorum), wild millet (Echinochloa walteri), beggarticks (Bidens spp.), spikerushes (Eleocharis spp.), bulrushes (Scirpus spp.), and common reed. A large portion in the center of the pool (approximately 35 acres) typically remains unvegetated or sparsely vegetated. Raymond Pool does not typically support the extent of annual vegetation that Shearness Pool does, but can provide good mudflat habitat to yield abundant invertebrate food supply for spring migrating shorebirds through a slow spring drawdown.

• Shearness Pool (440 acres) was formed in 1956 when a dike road was built to impound tidal salt marsh and hardwood swamp. The impoundment is adjacent to tidal salt marsh to the east and is connected to Raymond Pool by the Raymond-Shearness canal to the south. The dike separating the impoundment from the tidal salt marsh serves as a portion of the wildlife drive open to the public. Vegetation within the majority of Shearness Pool typically includes fall panic grass, wild millet, sprangletop (Leptochloa fasicularis), sedges (Cyperus spp.), beggarticks, spikerushes, bulrushes and common reed. Shearness Pool is managed primarily to provide annual food plants and suitable conditions to promote invertebrate food resources and cover for migrating and wintering waterfowl in the fall and winter. Shearness can also be managed to provide mudflat habitat to promote invertebrate food abundance for migrating shorebirds moving through the refuge in the following spring.

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• Finis Pool (10 acres) was completed in 1944. Finis Pool is located upstream and feeds directly into Shearness Pool by way of two water control structures. The lower portion of Finis is represented by a shrub-scrub swamp, while the upper end (extending to the west beyond Route 9) is dominated by red maple swamp. Typically, the stop logs in the Finis water-control structures remain set at a fixed elevation, allowing the water to rise and fall with weather events. Finis maintains some water even during drought and is used by breeding wood ducks (Aix sponsa), passerines, waders, and extensively by roosting waterfowl in the fall. Historically, this impoundment was defined as a larger area of approximately 200 acres, encompassing much of what is currently perennial scrub-shrub and forested wetland habitat and included in the Semi- permanent Freshwater Wetland habitat below. As an impoundment, Finis Pool has been redefined to include just the smaller area that is affected by the limited water management that takes place there.

• Bear Swamp (152 acres) was completed in 1961. Bear Swamp is dominated by large stands of common reed and cattail (Typha spp.), interspersed with flats of spikerush, bulrush, and sprangletop. The substrate of Bear Swamp is largely made up of a floating organic soup that cannot support equipment other than a canoe or airboat.

Semi-permanent Freshwater Wetland. Approximately 300 acres of semi-permanent freshwater wetlands exist on the refuge. West of Shearness Pool impoundment is approximately 138 acres of perennial scrub- shrub wetland consisting of buttonbush (Cephalanthus occidentalis), black willow (Salix nigra), and red maple that was formerly classified as part of Finis Pool. An additional 41 and 37 acres of persistent wetland exists in Bear Swamp and Raymond Pools, respectively. The remaining approximate 85 acres of this habitat exists as 43 unique areas throughout the refuge which range in size from ranging from 0.1 acre to 14 acres. Grassland and Shrubland Habitats The refuge has a history of managing some fields as grasslands and shrublands, including planting and maintaining warm season grassland fields. However, most of the current 595 acres of grassland and shrubland habitat on the refuge occurs in fields that were originally converted from forest and then farmed until 2010. This community is dominated by mixed grasses and forbs, and in later successional stages shrubs and scattered tree saplings including sweetgum, tuliptree, dogwood, maple (Acer spp.), cherry (Prunus spp.), and other species. While grasslands and shrublands are not technically a native community at the refuge, early successional habitat management with periodic mowing and prescribed fire provides the disturbance necessary to maintain grassland habitats for grassland-dependent species. Because of the inability to gradually transition old farm fields after cooperative farming was stopped, grasslands and shrubland habitats on the refuge require extensive invasive plant species control along with native planting efforts to diversify old fields. WILDLIFE Birds Two hundred seventy-eight bird species have been identified on or seen from the refuge, most of which are migratory and occur only seasonally. Spring migration includes waterfowl, wood warblers, and shorebirds. Summer residents include herons, egrets, American avocets (Recurvirostra americana), black- necked stilts (Himantopus mexicanus), and terns (Sterna spp.). Fall and winter months provide resting and wintering grounds for Canada geese (Branta canadensis), snow geese (Chen caerulescens), and a variety of waterfowl. Birds of prey are seen all year long. Waterfowl. Waterfowl utilize the refuge all winter and return during spring migration, peaking during migration (March and November). Species common in the managed freshwater impoundments include Canada geese, mallards (Anas platyrhynchos), northern pintail (Anas acuta), northern shovelers (Anas

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clypeata), green-winged teal (Anas carolinensis), and other dabbling ducks. American black ducks (Anas rubripes) breed in the refuge salt marsh and use salt marsh and impoundment habitats during the winter. Diving ducks, such as bufflehead (Bucephala albeola) and hooded mergansers (Lophodytes cucullatus), utilize deeper areas of the impoundments and tidal channels in the salt marsh. Wood ducks breed in the wooded wetlands found around the refuge, sometimes using nest boxes maintained by refuge volunteers. Shorebirds. The Delaware Bay is a major migration route and staging area for many species of shorebirds, and thousands of shorebirds feed along coastal beaches, interior salt marsh mudflats, and within managed impoundments. Shorebird numbers peak during spring (northbound) migration, and again in late summer during the fall (southbound) migration. The most common species, using both salt marsh and managed impoundment habitats, include semipalmated sandpipers (Calidris pusilla), least sandpipers (Calidris minutilla), semipalmated plovers (Charadrius semipalmatus), black-bellied plovers (Pluvialis squatarola), and dunlins (Calidris alpine). Many other species are observed less regularly or in smaller numbers; for example, the federally threatened red knot (Calidris canutus) is known from surveys to occasionally utilize Bombay Hook NWR coastal “pocket beaches” where the refuge salt marsh meets the Delaware Bay. Willets (Tringa semipalmata), a bird of high conservation concern in BCR 30, are common breeders throughout the refuge salt marsh. Black-necked stilts nest in refuge impoundments, especially Bear Swamp Pool. Killdeer (Charadrius vociferous) nest in various areas, from gravel parking lots to managed fields. The American woodcock is also found in areas containing shrubs and early successional forest growth. Waterbirds and Marsh Birds. There are a number of waterbirds and marsh birds that utilize the refuge’s extensive freshwater and tidal marsh habitats. Herring gulls (Larus argentatus) and great black-backed gulls (Larus marinus) are present year-round and are the most common gull species sighted. Forster’s terns (Sterna forsteri) and other terns are also common. Wading birds, including great blue herons (Ardea herodias), great egrets (Ardea alba), and snowy egrets (Egretta thula), are plentiful at the refuge, with many feeding in the impoundments as water levels are drawn down in summer. Black-crowned night herons (Nycticorax nycticorax) are commonly seen in the trees at the edge of the impoundments. Clapper rails (Rallus crepitans) are abundant and breed in tidal marshes during summer months. Black rails (Laterallus jamaicensis), a species of conservation focus in tidal marshes, have been documented as well, though in lower numbers. Virginia rails (Rallus limicola) are known to utilize refuge impoundments. Other secretive marshbirds in the tidal marsh include least bitterns (Ixobrychus exillis), soras (Porzana carolina), and king rails (Rallus elegans). Landbirds. The diverse vegetation communities on the refuge provide habitat for a variety of landbirds during the breeding season, as well as during migration and overwintering. Migratory species such as wood thrush (Hylocichla mustelina), eastern towhee (Pipilo erythrophthalmus), red-eyed vireo (Vireo olivaceus), scarlet tanager (Piranga olivacea), common yellowthroat (Geothlypis trichas) and Acadian flycatcher (Empidonax virescens) breed in refuge woodlands and mature forests. Early successional habitats are home to field sparrows (Spizella pusilla), grasshopper sparrows (Ammodramus savannarum), northern bobwhite quail (Colinus virginianus), and indigo bunting (Passerina cyanea). The salt marshes are dominated by seaside sparrows (Ammodramus maritimus), marsh wrens (Cistothorus palustris), red- winged blackbirds (Agelaius phoeniceus), and swamp sparrows (Melospiza georgiana). Saltmarsh sparrows (Ammodramus caudacutus) are present, although less common. Resident landbirds common year-round include American goldfinch (Spinus tristis), northern cardinal (Cardinalis cardinalis), Carolina chickadee (Poecile carolinensis), Carolina wren (Thryothorus ludovicianus), and several sparrow and woodpecker species. The refuge is particularly important to landbirds during fall migration, as documented by recent radar studies (Buler and Dawson 2014). The refuge’s forest and shrubland habitats located along the western shore of Delaware Bay coast provide an important “hotspot” stopover area for landbirds making the flight across the water. Raptors. The most common, year-round residents are turkey vulture (Cathartes aura), northern harrier (Circus cyaneus), red-tailed hawk (Buteo jamaicensis), red-shouldered hawk (Buteo lineatus), and

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American kestrel (Falco sparverius). Bald eagles (Haliaeetus leucocephalus) have nested successfully on the refuge for many years and use the refuge for feeding and roosting during the non-breeding season. Mammals The variety of habitats at Bombay Hook NWR provides essential food and cover requirements for approximately 35 mammal species can be found on the refuge, although there is little data on occurrence of most species. Those most frequently observed, especially in the early morning and the late afternoon, are the eastern cottontail, woodchuck (Marmota monax), gray squirrel (Sciurus carolinensis), red fox, and white-tailed deer. Less commonly observed are northern raccoon, striped skunk (Mephitis mephitis), Virginia opossum (Didelphis virginiana), and muskrat (Ondatra zibethicus). River otters (Lontra canadensis) are present, but uncommon, in the tidal marshes. Bat surveys were conducted in 2004-2005 and three species were documented through mist-netting (big brown bats (Eptesicus fuscus), eastern red bats (Lasiurus borealis), and hoary bat (Lasiurus cinereus) (Fox 2007), though other bat species are likely. Reptiles and Amphibians There is little data about the reptiles and amphibians communities on the refuge. However, the list of 35 species known or believed to occur on the refuge was updated in 2013 with the help of volunteers with herpetological experience. Common reptiles include snakes such as black rat snakes (Pantherophis obsoletus), eastern garter snakes (Thamnophis sirtalis sirtalis), and northern water snakes (Nerodia sipedon). Eastern box turtles (Terrapene carolina carolina) can be found in refuge forests and woodlands; common snapping turtles (Chelydra serpentina), eastern mud turtles (Kinosternon subrubrum), and painted turtles (Chrysemys picta) are common in ponds and freshwater wetlands; and the diamondback terrapin (Malaclemys terrapin) is abundant in the refuge tidal marshes. The spotted turtle (Clemmys guttata), a less common species of conservation concern, has been documented on the refuge. Two lizard species, the five-lined skink (Plestiodon fasciatus) and northern fence lizard (Sceloporus undulatus), are known to occur on the refuge. Fowler’s toad (Anaxyrus fowleri), American bullfrogs (Lithobates catesbeianus), green frogs (Lithobates clamitans), spring peepers (Pseudacris crucifer), and a number of other frog and toad species are also common. Invertebrates The refuge has limited data on the occurrence of invertebrate species on the refuge. Moist soil management strategies used in the refuge impoundments support breeding populations of insects such as chironomids, which are important food for migrating shorebirds. A small survey of bee species was done in 2008 in four fallow fields on the refuge, and 18 species or genuses were detected (L. Shapiro, unpub. data). The researchers noted that three species of Melissodes were present along with one of their uncommon nest parasites, the eucera cuckoo omad bee (Triepeolus cressonii). Also present was hibiscus bee (Ptilothrix bombiformis), reflecting the native mallows in the brackish and fresh water portions of the marshes. Number of individuals and species totals fell within what would be expected from the region. Other important invertebrate species are known to occur in refuge waterways and tidal wetlands, such as oysters, freshwater mussels, fiddler crabs, and blue crabs (Callinectes sapidus). Fish Brackish water habitat on the refuge hosts several species of killifish, the most common of which are mummichogs (Fundulus heteroclitus), banded killifish (Fundulus diaphanous), and sheepshead minnow (Cyprinodon variegatus variegatus). During the winter months, killifish tend to stay in the deeper areas, sometimes buried in the mud. The main source of food for killifish species is mosquito larvae, and they are a major food source for wading birds (egrets) and northern raccoons. Finis Pool and the other impoundments host the eastern mudminnow (Umbra pygmaea), killifish, and occasional sunfish. Bear Swamp fish include pumpkinseed sunfish (Lepomis gibbosus) and brown

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bullhead catfish (Ameiurus nebulosus). The abundance of fish make this pond a very good spot to observe herons, egrets, and the occasional belted kingfisher (Megaceryle alcyon). The marshes are nurseries for many fish species, which are important food sources for many birds. Egrets, herons, and some of the diving ducks like hooded mergansers feed on small fish, including killifish, Atlantic silversides (Menidia menidia), and juvenile white perch (Morone americana). Adult striped bass (Morone saxatilis), white perch, and American gizzard shad (Dorosoma cepedianum) are important for nesting bald eagles and their young, ospreys (Pandion haliaetus), northern raccoons, and river otters. Special Status Species There are no known federally listed threatened/endangered species that breed on the refuge. Federally threatened red knots are known to use the refuge’s impoundments and limited beach habitats during migration, although not consistently or in large numbers. The following state listed endangered species have been documented as nesting on the refuge: American kestrel, Forster’s tern, northern harrier, pied- billed grebe (Podilymbus podiceps), and sedge wren (Cistothorus stellaris). AQUATIC RESOURCES / WATER QUALITY The Water Resources Inventory and Assessment (WRIA; Wurster et al. 2013) has an extensive discussion of aquatic resources in Bombay Hook NWR. Refer to the WRIA for further details; information relevant to this HMP is summarized below. The Delaware Bay makes up the eastern boundary of the refuge and is the major estuary outlet of the Delaware River. It spans 782 square miles between Delaware and New Jersey and represents a zone of freshwater-saltwater mixing into the Atlantic Ocean. For most of their length, streams at Bombay Hook are considered estuaries with daily tidal fluctuations and brackish water (Wurster et al 2013). In the largest tidal streams, the tidal range is between 4.52 and 5.58 feet, with a range of 3.28 feet or less in the smaller guts. On many streams, tide gates, levees, low-head dams, and roads control how far brackish water extends upstream. The headwaters of Kent County freshwater streams are typically low-gradient seeps with poorly defined channels that flow towards Delaware Bay. One stream at Bombay Hook NWR, the Leipsic River, has been identified as an impaired waterbody and is listed in the Delaware’s impaired waters (i.e., 303(d) listed) due to levels of total coliform, dissolved oxygen, and nutrients. The DNREC developed Total Maximum Daily Loads (TMDLs) for the Leipsic River, which were approved by the EPA in 2008. The TMDL for the river sets load allocations for nitrogen, phosphorus, and Enterococcus bacteria, mostly entering the watershed from agricultural runoff upstream outside the refuge boundaries. Secondary concerns include potential pollutants that may enter the refuge from the Delaware Bay, including the occurrence and ongoing risk of oil spills from tankers that regularly traverse the channel to access the Port of Delaware. GEOLOGY Bombay Hook NWR is found in the Atlantic Coastal Plain of Delaware, which is composed of sediments that have been deposited by the erosion of the Appalachian Mountains and marine sediments deposited as a result of frequently fluctuating sea levels. The thickness of the sediments in the Atlantic Coastal Plain approaches 10,000 feet in the vicinity of the refuge. Underlying these sediments is bedrock that is thought to be of the same origin as rocks found in the Piedmont of northwestern Delaware. The Atlantic Coastal Plain today is a region of little topographic relief, with broad, slow-moving streams and extensive tidal estuaries (Hess et al. 2000). Ground surface elevations on the refuge are lower than 10 feet above sea level. The geology of the Delaware Bay’s coastline is part of larger geological structure known as the Atlantic Coastal Plain-Continental Shelf Geosyncline. This structure is known to be subsiding regionally, or sinking, relative to adjacent land at a rate of 1.7 mm/year (Engelhart et al. 2009). On a local scale, the

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coastal portions of Kent County are experiencing rates of subsidence that far exceed the regional average rate with rates of 3.11 mm/yr to 4.03 mm/yr (Holdahl and Morrison, 1974). This shoreline of the entire lower Delaware Bay is migrating in a landward direction due to subsidence, sea level rise, and coastal erosion; and the effects of these three processes are observable on the refuge. Sea level rise is further discussed in Section 2.12. The erosion and redistribution of sediments in the active coastal littoral zone further influences the shoreline shift in a landward and upward direction (Kraft et al. 1976). SOILS As stated in the WRIA (Wurster et al. 2013), there are 24 soil mapping units at Bombay Hook NWR. Seventy-nine percent of the soils on the refuge are hydric, with the Broadkill-Appoquinimink Complex and Transquaking and Mispillion soils comprising 70 percent of the area within the refuge. Both units are tidal marsh soils composed of peat and mucky silt loams produced from a combination of decomposing marsh vegetation and marine sediments. They are flooded frequently and have a relatively unconsolidated structure. The upland soils were derived from medium-grained fluvial/marine parent materials with some locally derived silt loess caps. The soils range in natural drainage class from poorly drained hydric soils (Elkton silt loam, Fallsington loam) to well drained soils on the upland interfluves (Nassawango silt loam, Downer sandy loam). THREATS TO MANAGEMENT AND CONSERVATION Threat Characterization Understanding and identifying the factors adversely affecting the refuge’s capability to fulfill its legislated purposes, USFWS goals, and habitats managed are an important component to define management strategies. Instead of creating a formal threat list, the planning team adapted the conservation threat hierarchy developed by the International Union for Conservation of Nature (IUCN), an internationally regarded organization working with and categorizing species and habitats threatened with decline and extinction. For over 50 years, the IUCN Red List has provided a global database and evaluation criteria for at-risk species (IUCN 2016). For our planning purposes, the planning team adapted the framework to consider the ecological threats to the refuge as a whole, rather than individual species. While the full Threats Classification Scheme (Version 3.2) with 12 categories in a defined Hierarchy of Classification (1.0 to 12.0) is not outlined here, each category except “Other” is described briefly as it relates to the refuge. Narratives describing the threat categories are presented in the order they appear on the IUCN classification scheme. IUCN also contains a framework by which threats can be categorized according to timing, scale, and severity of each threat (Table 2-4).

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Table 2-4. International Union for Conservation of Nature Threat Category Considerations Scale of Impact Timing Considerations Severity to Ecological Integrity Considerations Considerations

Only in the past and unlikely to Affects the entirety of the Causing or likely to cause very rapid declines return managed area (>90%) Causing or likely to cause rapid declines In the past but now suspended Affects the majority of the Causing or likely to cause relatively slow but and likely to return managed area (50-90%) significant declines Ongoing Affects the minority of the Causing or likely to cause fluctuations managed area (<50%) Only in the future Causing or likely to cause negligible declines Unknown Unknown No declines Unknown

The influences of these threats can impact the severity of other related threats facing habitat management. Figure 2-8 diagrams the severity and relation of eight conservation threats to the refuge habitats. The relative weight of the arrows between the threats in Figure 2-8 denotes the relative influence of the threat on refuge resources; the dotted arrows show where threats are connected and can influence the risk, experience, or intensity of a threat. Threats not present at Bombay Hook NWR, or believed to have minimal or no impact to refuge habitats, are not included in the diagram below.

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Figure 2-8. Threats Influencing Habitat Condition and Management on Bombay Hook NWR*

* Threats are based on IUCN categories and those that are negligible in their perceived impact are not shown (e.g., Energy Production and Mining, Biological Resource Use, Human Intrusions and Disturbance, and Other)

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Threat: Residential and Commercial Development

Timing Scale Severity

Affects the majority of the Causing or likely to cause Ongoing managed area (50-90%) fluctuations

This category encompasses threats from human settlements or other non-agricultural land uses with a substantial footprint. As noted, the refuge area experienced a long history of settlement. With the refuge’s location, only a few hours from major metropolitan areas for Philadelphia and Baltimore, plus many other mid-sized cities, ongoing development in lands adjacent to the refuge are a continual concern. While the refuge is designated with no potential for future residential, commercial, or industrial development within its boundaries, the land uses surrounding can have direct impacts on the refuge itself and the wildlife present. Development poses a multi-faceted threat by creating abrupt land use changes, altering ecosystem inputs (vegetation, hydrology, and connectivity), limiting migration between available or potential habitats (fragmentation), and restricting the ability of habitats to shift or respond to changes in land use or sea levels. Residential properties and adjacent roads can also be vectors for other threats noted in this section. In 2017 Delaware was the 6th most densely populated state in the United States, with an estimated 961,939 residents occupying roughly 1,949 square miles at a population density 461 persons per square mile (U.S. Census Bureau 2017). By contrast, Kent County population density is 277 persons per square mile. Although development pressure and encroachment of population centers is not currently a significant threat to the refuge, Kent County includes the capital city of Dover, and as population continues to grow it is anticipated that residential and commercial development will become increasingly substantial (Delaware Office of State Planning Coordination 2015). In Kent County, between 2008 and 2013, more than 99 percent of all residential units approved by local governments were in areas targeted for growth (DNREC 2015). The State’s projected growth, combined with the significant amount of development activity in natural areas, represents a major concern for the conservation of habitats important to wildlife in Delaware and throughout the Delmarva Peninsula. As regional development continues, the role of protected lands such as Bombay Hook NWR becomes increasingly important for preserving biodiversity, protecting species, and the ecological integrity of habitat they rely on. Threat: Agriculture and Aquaculture

Timing Scale Severity

Affects the minority of the Causing or likely to cause Ongoing managed area (<50%) fluctuations

This category includes threats from the expansion and intensification of farming and ranching practices, including silvilculture, mariculture, and aquaculture (nutrient and sediment effluents are considered in threat section on Pollution). Agriculture and aquaculture are similar to residential and commercial development as they provide fixed boundaries that can isolate and restrict the dynamics of interior ecosystems. Additionally, non-native or crop species and domesticated livestock can encroach upon, and thusly contribute additional impacts to, species diversity within refuge boundaries. Delaware has over 2,500 farm operations that cover nearly 500,000 acres (or 53% of the land) (U.S. Department of Agriculture 2017). Typical commodities produced include corn, soybeans, wheat, melons, hay, barley, beans, cucumbers, livestock, and milk. While the expansion of agriculture is not an extensive

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threat to the refuges, existing agriculture operations are adjacent to refuge boundaries and have had ongoing impacts to the refuge throughout its history. More than a third (183,000 acres) of Delaware’s farmland acreage is in corn (DNREC 2015). According to the Delaware Extension Service (2015), Delaware corn yields have increased four-fold since the 1930s to an estimated 125 bushels per acre in 2011 (as cited in DNREC 2015). Factors that have increased yields include increased breeding efforts including those that developed hybrid seed corn, commercial fertilizer manufacturing and use, modern pesticides, and the increase in irrigation. This intensification of agriculture off-refuge poses on-refuge threats in the forms of: • Groundwater loss, which may lead to saltwater intrusion and the gradual conversion of terrestrial habitats to more saline-tolerant vegetation.

• Pesticide drift, which can unintentionally result in direct impacts to wildlife, or damage or degradation of refuge vegetation, depending on the type and concentration of the chemicals used.

• Eutrophication of waters, which can further degrade aquatic habitat on and adjacent to the refuge. Threat: Energy Production and Mining

Timing Scale Severity

Affects the minority of the Only in the future No declines managed area (<50%)

Threats can arise from production of non-biological resources, such as exploring for, developing, and producing petroleum and other liquid hydrocarbons, minerals and rocks, or renewable energy. There is no active energy production or mining on or near the refuge. There remains the potential for renewable energy production on or near the refuge in the future. Threat: Transportation and Service Corridors

Timing Scale Severity

Affects the minority of the Causing or likely to cause Ongoing managed area (<50%) negligible declines

Roads and utility lines fragment habitat and decrease habitat connectivity as they can act as barriers for animal movement. Fragmentation and reduced dispersion causes gene flow issues, which can lead to localized extinctions. Roads and utility corridors often serve as pathways for non-native species introduction and spread and can have other impacts related to other threats such as noise, air pollution, contamination, or direct collisions. Following initial disturbance from construction, roads and utility lines continue to facilitate regular traffic, including daily vehicle use, and require periodic maintenance, such as to keep utility lines free from vegetative interference. There are no utility structures within the refuge and the main road through the refuge, Wildlife Drive, is a low-use/slow speed road; however, an extensive system of public roads and utility facilities adjacent to the refuge can provide similar disturbance influences.

Threat: Biological Resource Use

Timing Scale Severity

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Affects the minority of the Ongoing No declines managed area (<50%)

Biological resource uses refer to the consumptive use of "wild" biological resources. Hunting can occur on the refuge. However, these activities are highly regulated and seasonally prohibited. As a result, they are managed in a manner that is not known to engender significant risk to wildlife populations. Hunting can also have benefits as a management tool for habitats by decreasing the browsing disturbance from an overabundant deer population and benefit wildlife habitats. Threat: Human Intrusions and Disturbance

Timing Scale Severity

Affects the minority of the Ongoing No declines managed area (<50%)

Threats from human activities that alter, destroy, and disturb habitats and species associated with non- consumptive uses of biological resources become increasingly detrimental to the trust resources utilizing public lands as recreation pressure increases. Noise and light pollution are specific stressors associated with this threat that can cause distress (e.g., flushing, nesting failure) in less tolerant species. Recreational activities on Bombay Hook NWR that have the potential to interfere with management objectives and activities as well as harass and stress resident species onsite include non-permitted on- and off-trail birdwatching and nature photography. Threat: Natural System Modifications

Timing Scale Severity

Only in the past and unlikely Affects the majority of the Unknown to return managed area (50-90%)

These threats arise from actions that convert or degrade habitat with the intent of “managing” natural or semi-natural systems to a designated endpoint or suppressing natural disturbances, often for human- centric purposes. Such modifications can include altering fire frequency and/or intensity outside of the natural range of variation appropriate for a given ecosystem or climate, and the implementation of water management infrastructure to manipulate water levels in a given area. While land management is often not perceived as a typical “threat,” the evolution of ecosystem understanding or changing perspectives, strategies, and outcomes may recontextualize actions that were initially well intended. As demonstrated by the history of management at Bombay Hook NWR, intended management for wildlife and habitats can sometimes lead to unintended and persistent conditions in the landscape. These human-caused landscape modifications are evident throughout the refuge, and historically generally followed the best science and techniques available at the time they were employed (see Section 2.2). Hydrologic alterations were at one point extensive, and many ditches, canals, and structures are maintained and utilized to continue to maintain a given desirable, yet likely unnatural, endpoint Over the decades of management at Bombay Hook, much has been learned, both in habitat and wildlife response to management actions, as well as in the broader fields of conservation science, ecological restoration, and wildlife biology. As the refuge continues to learn from, and apply, current science and management tools, unintended impacts from management will be avoided or minimized. Threat: Invasive and Other Problematic Species, Genes, and Diseases

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Timing Scale Severity

Causing or likely to cause Affects the majority of the Ongoing relatively slow but significant managed area (50-90%) declines

This category includes threats from non-native and native plants, animals, pathogens/microbes, or genetic materials that could have harmful effects on biodiversity following their introduction, spread and/or increase in abundance. Invasive species pose one of the most substantial threats to natural communities and can eventually create monotypic stands when left unchecked. Pervasive establishment of invasive species populations results in reduced biodiversity in an area (i.e., biosimplification), and can alter food webs, habitat structure, and reduce biological integrity. Table 2-5 provides a comprehensive survey of problematic species occurring on the refuge. Most of these species establish quickly and reproduce prolifically, and some have created extensive monocultures throughout the refuge. While some species provide wildlife cover and nectar resources (e.g., for pollinators, including monarch butterfly [Danaus plexippus]), they can ultimately decrease biodiversity if allowed to dominate in certain areas. Major threats include Canada thistle (on state list of noxious species so refuge is obligated to actively and aggressively manage) and common reed (in select areas). Other problematic wildlife that occur on the refuge include mute swans and resident Canada geese, which tend to alter their habitat in a way that excludes more sensitive species in the landscape.

Table 2-5. Problematic Species on Bombay Hook NWR Invasive Species Scientific Name Refuge Control Efforts Plants Canada thistle Cirsium arvense Mowing and Herbicide Common reed Phragmites australis Herbicide

Spotted knapweed Centaurea maculata Mowing and Herbicide Garlic mustard Alliaria petiolata [Anticipating future invasion] Japanese honeysuckle Lonicera japonica None Mile-a-minute-weed Persicaria perfoliata Released beetles in Delaware for biological control but have not yet been effective Japanese stiltgrass Microstegium vimineum None Multiflora rose Rosa multiflora Herbicide and Mowing

Autumn olive Elaeagnus umbellata Herbicide

Johnsongrass Sorghum halepense Herbicide and Mowing Wildlife Canada goose (resident) Branta canadensis Occasional control Mute swan Cygnus olor As needed Diseases Bacterial leaf scorch Xylella fastidiosa No known control available Red/white oak disease Bretziella fagacearum No known control available Invertebrates Emerald ash borer Agrilus planipennis [Anticipating future invasion] Asian longhorn beetle Anoplophora glabripennis None

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Table 2-5. Problematic Species on Bombay Hook NWR Invasive Species Scientific Name Refuge Control Efforts Spotted lanternfly Lycorma delicatula [Anticipating future invasion] Gypsy moth Lymantria dispar Monitoring for presence Southern pine beetle Dendroctonus frontalis [Although, not many pines onsite] Asian tick (vector for Haemaphysalis longicornis Monitoring multiple diseases)

Threat: Pollution

Timing Scale Severity

Affects the majority of the Causing or likely to cause Ongoing population (50-90%) fluctuations

Pollution experienced by Bombay Hook NWR may be continuous, such as that derived from runoff, effluent, and emissions, or episodic, such as spills. Pollutants have ongoing impacts to water, sediment, and air quality and originate from domestic and urban, industrial and military, and agricultural and forestry activities. In general, due to the extensive population pressures, development density, and the age of much of the infrastructure in the region, the Northeast generally experiences low air and water quality (DE WAP, DNREC 2015) (see Section 2.4, Air Quality and Section 2.7, Aquatic Resources/Water Quality). Pesticides that drift from neighboring agricultural areas may also impact non-target invertebrates on the NWR, particularly bees and other pollinators or food species for bird populations. The risk of spills from transportation of oil through Delaware Bay is a persistent threat to adjacent ecosystems. As stated in the DE WAP, the port complex of the Delaware River and Bay is the second largest oil port in the United States, handling about 85 percent of the East Coast's oil imports (DNREC 2015). There have been past spills that have released significant volumes of oil into the Delaware River and Bay estuaries, and likewise the direct effects of high-volume spills and clean-up efforts as well as the cumulative effects of smaller spills can have ongoing impacts to resources in the watershed.

Threat: Geologic Conditions

Timing Scale Severity

Causing or likely to cause Affects the whole population Ongoing relatively slow but significant (>90%) declines

As discussed in Section 2.9, Geology, the Atlantic Coastal Plain-Continental Shelf Geosyncline is subsiding at a rate of 1.7 mm/year, with localized higher rates (Engelhart et al. 2009, Holdahl and Morrison 1975). It is not well documented in the refuge area what effects groundwater withdrawal and reduced recharge (from the underlying confined aquifer) have upon localized subsidence rates. As the elevation of the refuge generally does not exceed 10 feet above sea level, and because the majority of the refuge is directly adjacent to the Delaware Bay shoreline, subsidence coupled with climate change and severe weather could provoke significant ecosystem shifts if salt or brackish water intruded further inland. These impacts would be especially detrimental if sea level rise or major storm events reached inland freshwater wetlands currently hydrologically isolated from the Bay.

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Threat: Climate Change and Severe Weather

Timing Scale Severity

Affects the whole population Causing or likely to cause rapid Ongoing (>90%) declines

Climate change and extreme weather events, sea level rise, and altering weather/precipitation patterns may pose serious impacts to habitats on the refuge and the resources that depend on it for all, or part, of their lifecycle. Fixed refuge boundaries, constrained by human land use, restrict the migration potential of species as climate alterations may favor non-target species proliferation. Although Bombay Hook NWR was relatively unaffected by Hurricane Sandy in 2012, other refuges and habitats in the region experienced wide-scale damage. Delaware is particularly vulnerable to the effects of climate change, especially estuarine wetlands and other coastal habitats, as sea level rises and storms are more frequent and intense. Sea-level rise has increased in its local relative rate over the past 1,200 year from 0.9 mm/yr to 3.3 mm/yr, which has increased the rate of shoreline and wetland transgression (Nikintina et al., 2000). These shifts also impact the overall distribution and health of the wetland resources of the refuge. The DE WAP (2015) has an extensive discussion of potential impacts to Delaware ecosystems. Additional mapping and modeling resources include: • The Northeast Climate Science Center (NECSC) has synthesized a repository of climate change information and produced modeling and other data resources to help predict potential impacts in the 22 Northeastern states (University of Massachusetts; http://necsc.umass.edu/ ). • Manomet, Inc. uses an interdisciplinary approach to develop science-based climate impacts management guidance (https://www.manomet.org/climate-services ). Bombay Hook NWR has adopted a Sea Level Affecting Marshes Model (SLAMM; USFWS 2010b) that maps potential climate change-related transition and migration of coastal wetlands throughout the refuge. Although the technological capability and reliability of model simulations is always improving, the 2010 SLAMM at Bombay Hook NWR predicts dramatic losses of wetlands at around one meter of eustatic sea level rise (SLR), anticipated in some scenarios by 2100. Predicted loss rates from this effort are reproduced in Table 2-6 (USFWS 2010b). Incremental SLR may increase saltmarsh habitat as freshwater and irregularly flooded marsh is converted; but above 1m SLR, 84 percent of Bombay Hook NWR’s regularly flooded (salt) marsh would also be lost. The refuge is predicted to lose between 23 percent and 62 percent of its dry land, and between 15 percent and 97 percent of its irregularly flooded marsh across all scenarios. Note that these estimates do not necessarily account for additional, convergent threats that would further impact vulnerable nearshore habitats, including subsidence, erosion, and storm events that may further weaken infrastructure currently acting as the barrier between salt and freshwater habitat.

Table 2-6. Predicted Change in Land Categories by 2100 Given Simulated Scenarios of Eustatic Sea Level Rise*

Bombay Hook Simulated Scenarios of Eustatic Sea Level Rise By Year 2100 (m) NWR Habitat 0.39 0.69 1 1.5 2 Saltmarsh 1% 7% 9% -84% -94% Undeveloped -23% -31% -38% -50% -62% Dry Land Irregularly -15% -37% -83% -95% -97% Flooded Marsh

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Estuarine Beach -2% -2% -2% -3% -95% Swamp -28% -38% -45% -54% -64% Inland Fresh -7% -10% -13% -18% -27% Marsh * Table is adapted from USFWS 2010b; Positive values represent increases, negative values represent losses.

Wetland on Wildlfe Drive

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CHAPTER 3. RESOURCES OF CONCERN 3.1 INTRODUCTION Resources of Concern (ROC) are the focal point of an HMP. The HMP policy (620 FW 1) defines ROC as: All plant and/or animal species, species groups, or communities specifically identified in refuge purpose(s), System mission, or international, national, regional, state, or ecosystem conservation plans or acts. For example, waterfowl and shorebirds are a resource of concern on a refuge whose purpose is to protect "migrating waterfowl and shorebirds.” Federal or State threatened and endangered species on that same refuge are also a resource of concern under terms of the respective endangered species acts. The USFWS is entrusted by Congress to conserve and protect Federal trust species, including migratory birds, federally listed threatened and endangered species, inter-jurisdictional fish, and certain marine mammals. Each refuge also has its own specified purpose(s) for which it was established, which guides its management goals and objectives. Within these purposes, refuges support other elements of biological diversity such as locally rare plant, invertebrate, and vertebrate species and natural communities, and the ecological processes that contribute to the BIDEH at the refuge, ecosystem, and broader scales (601 FW 3). Identifying ROC allows each refuge to identify management unit and refuge-wide objectives aimed at maintaining, increasing, and/or improving the habitats required by trust resources and populations identified in the refuges’ purpose. Concurrent with the IMP process, the ROC process facilitates a targeted approach to identifying priority areas and/or gaps in management that may require additional resources, such as information (data collection and monitoring) or staff and equipment. As individual species respond to habitat management differently, identifying ROC allows refuge staff to focus management activities at the level that yields the greatest benefit to trust resources, complimenting BIDEH and the refuge purpose(s). 3.2 IDENTIFICATION OF RESOURCES OF CONCERN For the purposes of this chapter, we (refuge staff and the planning team) used the term comprehensive ROC to refer to a subset of resources of concern identified in the DE WAP and the USFWS Northeast Region list of at-risk species that are known to occur on the refuge. Candidate ROC refers to species from the comprehensive ROC list considered further for selection as a priority ROC. Priority ROC refers to species selected to guide and prioritize management strategies with the goal of enhancing and managing habitat on the refuge for the life of the HMP. The first step in developing a focused habitat management strategy is to define a refuge’s candidate ROC in light of the multiple mandates (see Section 1.3), refuge purposes (see Section 1.3.3), policies (see Section 1.4.1), and regional/national plans (see Section 1.4.2). Table 1-2 identifies the national and regional conservation plans we considered relevant to Bombay Hook NWR in candidate ROC selection. The master list of species as identified by each plan was compared to the comprehensive ROC list (Appendix B) to generate a list of candidate ROC. We narrowed down the list of candidate ROC to select priority ROC, or species most likely to represent a suite of habitat needs for other species, using the process defined in Section 3.4.1. We used a list of habitats that represent BIDEH at the refuge to ensure that the suite of priority ROC were selected to represent all major habitat types under Bombay Hook NWR responsibility.

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IDENTIFICATION OF BIOLOGICAL INTEGRITY, DIVERSITY, AND ENVIRONMENTAL HEALTH Defining Biological Integrity, Diversity, and Environmental Health The Refuge System Improvement Act of 1997 states that, in administering the Refuge System, the Service shall “ensure that the biological integrity, diversity, and environmental health of the System are maintained” (see Section 1.4.1). The Service defines BIDEH (Service Manual 601 FW 3) as: • Biological Diversity - the variety of life and its processes, including the variety of living organisms, the genetic differences between them, and the communities and ecosystems in which they occur.

• Biological Integrity - biotic composition, structure, and functioning at genetic, organism, and community levels comparable with historic conditions, including the natural biological processes that shape genomes, organisms, and communities.

• Environmental Health - composition, structure, and functioning of soil, water, air, and other abiotic features comparable with historic conditions, including the natural abiotic processes that shape the environment. Identifying BIDEH at Bombay Hook NWR Bombay Hook NWR will manage for priority ROC with habitat needs that are found along a continuum of vegetation structure and hydrologic regimes within habitat types present on the refuge. To assess current and future potential conservation status, we reviewed historic information regarding habitats, management changes, species use within refuge authorized boundaries, and relevant literature describing requirements of selected ROC and ecosystem processes that regulate natural communities. The resources we used to describe the Bombay Hook NWR baseline environmental, abiotic, and biotic conditions include • Reports and associated unpublished refuge data regarding site history and capabilities.

• Refuge maps and aerial imagery of existing and historical vegetation types, including remote sensing and field-verified inventory of all vegetative community associations across management units.

• Delaware Wildlife Action Plan, 2015-2025 (DE WAP) (DNREC 2015).

• Status and trend information for species listed on the comprehensive ROC list from refuge staff observations or as documented in regional and local assessments and reports. Based on a review of the existing and historical data listed above, we developed a list of habitat types that contain elements of BIDEH to evaluate processes that influence the ecological and biological integrity of habitat types within the refuge (Table 3-1).

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Table 3-1 Summary of Habitats that Represent Existing BIDEH at Bombay Hook NWR

Natural Processes Responsible for HMP Broad DE WAP Limiting Factors / Threats Habitat Attributes1,2 Habitat Conditions or Wildlife Habitat Type1 Community2 Specific to Habitat1,2 Populations1,2

Tidal Salt Tidal Low Salt Dominated by smooth cordgrass and salt Longer submergence than Tidal High Salt Pollution from adjacent land uses, Marsh Marsh meadow cordgrass with occasional associates Marsh, periodic substrate exposure, moderate creation of “island” effect by adjacent such as glassworts, spearscale, groundselbush, salinity, moderately high levels of iron (7-15 development, maritime derived southern marsh elder, Virginia sea shore mallow ppm). Substrates include peat mixed with, or pollutants, invasive species, sea level (Kosteletzkya virginica), swamp rosemallow, overlying, a layer of sand or silty muck. rise, subsidence, and changes in waterhemp (Amaranthus cannabinus), saltmarsh Located in places that receive daily tidal salinity. fleabane, salt meadow cordgrass, giant flooding (e.g., along creek edges). Generally cordgrass, black-grass rush (Juncus gerardii), limited to the zone between mean low water seashore saltgrass, and common reed. There is and the mean high water level. little variation in vascular plant species composition across the range of this community. Microscopic algae may be abundant and include numerous diatoms, as well as other algal groups.

Tidal Salt Tidal High Salt Characterized by dominance of smooth cordgrass Herbaceous dominated communities receive Pollution from adjacent land uses, Marsh Marsh and and salt meadow cordgrass. Seashore saltgrass irregular tidal flooding and are at slightly creation of “island” effect by adjacent Shrubland (Distichlis spicata) often occurs within this higher elevations than the Tidal Low Salt development, maritime derived community. Other characteristic associates Marsh. pollutants, invasive species, sea level include sea-lavender (Limonium carolinianum), rise, subsidence, and changes in Shrub dominated communities are present at glassworts (Salicornia spp.), Olney’s three salinity. slightly higher elevations than associated square, seaside goldenrod (Solidago herbaceous communities within the Tidal sempervirens), saltmarsh fleabane (Pluchea High Salt Marsh. odorata), swamp rosemallow (Hibiscus moscheutos) and spearscale (Atriplex patula). The soil is often mucky, and is composed of peat that overlies sand and silt. Found in the Where at slightly higher elevations along the zone from the mean high tide limit to the borders with adjacent uplands and on localized limit of spring high tides. islands within the marsh complex, this habitat on the refuge is dominated by groundselbush and high-tide bush with southern bayberry (Morella cerifera) also occurring.

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Natural Processes Responsible for HMP Broad DE WAP Limiting Factors / Threats Habitat Attributes1,2 Habitat Conditions or Wildlife Habitat Type1 Community2 Specific to Habitat1,2 Populations1,2

Tidal Salt Reed Tidal Characterized by dense stands of common reed. Similar to other Tidal Salt Marsh Pollution from adjacent land uses, Marsh Marsh Other species may include Virginia sea-shore communities, but has been invaded by creation of “island” effect by adjacent mallow, false nettle (Boehmeria cylindrica), invasive species. development, maritime derived dogbane (Apocynum cannabinum), narrow-leaf pollutants, invasive species, sea level cattail (Typha angustifolia) and swamp rose rise, subsidence, and changes in (Rosa palustris). salinity.

Beach Sandy Beach Beaches on the refuge are limited to small Shifting sands, strong winds, and salt spray Pollution from adjacent land uses, pockets of sand over peat. along the Delaware bay. creation of “island” effect by adjacent development, maritime derived pollutants, invasive species, sea level rise, subsidence, and changes in salinity.

Beach Maritime Dune Salt meadow cordgrass and Cape American Located in areas where wave action from the Pollution from adjacent land uses, and Grassland beachgrass (Ammophilia breviligulata) are Delaware Bay has pushed sand and sediment creation of “island” effect by adjacent dominant. Total vegetation cover is variable, into the salt marshes during storm events. development, maritime derived ranging from sparse (25% cover) to dense (80% Storm overwash is a prevalent and ongoing pollutants, invasive species, climate cover). Typical co-dominants of salt meadow natural disturbance depositing water-borne change, sea level rise, subsidence, cordgrass and Cape American beachgrass are sand. Distinguished by a dominance of salt and changes in salinity. present, as well as seaside goldenrod. Species meadow cordgrass. Bare sand is often visible diversity in this community varies. through the vegetation and there is no soil profile development.

Upland Forest Mesic Mixed Canopy species include sweetgum and tuliptree. Develop on moist, acidic, often nutrient-poor Pollution from adjacent land uses, Hardwood Associated species include white oak, southern soils. Associated with ravines, lower slopes, creation of “island” effect by adjacent Forest red oak (Quercus falcata), American beech undulating uplands, and flatwoods. development, invasive species, (Fagus grandifolia) and red maple. Loblolly pine Distinguished by a mixture of deciduous climate change, subsidence, deer and Virginia pine may be sparsely scattered hardwood species and is perhaps the most browse. throughout. American holly is common in the common terrestrial vegetation community in understory, which overtops a shrub layer of southern New Castle and northern Kent highbush blueberry (Vaccinium corymbosum) Counties. and early lowbush blueberry (Vaccinium pallidum). The herbaceous layer is often sparse.

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Natural Processes Responsible for HMP Broad DE WAP Limiting Factors / Threats Habitat Attributes1,2 Habitat Conditions or Wildlife Habitat Type1 Community2 Specific to Habitat1,2 Populations1,2

Upland Forest Piedmont Oak Canopy species include Northern red oak, white Develop on well-drained loamy sand Pollution from adjacent land uses, Forest oak, mockernut hickory (Carya alba), pignut associated with ridges and upper slopes. creation of “island” effect by adjacent hickory (Carya glabra) and black oak. The Distinguished by high amounts of hickory development, invasive species, understory contains sassafras (Sassafras (Carya spp.) and the lack or low abundance climate change, subsidence, deer albidum), sweetgum, black cherry, and American of tuliptree and American beech. browse. holly. Arrow-wood (Viburnum dentatum) and raspberry (Rubus spp.) compose the shrub layer. Virginia creeper (Parthenocissus quinquefolia), New York fern (Thelypteris noveboracensis) and common blue violet (Viola sororia) are among the few herbs in this community.

Upland Forest Modified / Canopy species include black cherry, tuliptree, Species composition heavily modified by a Pollution from adjacent land uses, Successional white oak, northern red oak, red maple, and history of clearing or agriculture and creation of “island” effect by adjacent Forest sweetgum. Understory species include subsequent invasion of aggressive native and development, invasive species, spicebush, flowering dogwood (Cornus florida), non-native species. Commonly forms after climate change, subsidence, deer persimmon (Diospyros virginiana) and smaller the abandonment of agricultural fields and is browse. members of the overstory. The shrub layer can part of a succession. It is often not particular be dense with common greenbriar (Smilax to a geologic type but forest dominated by rotundifolia), poison ivy (Toxicodendron sweetgum are typically found on soils with radicans), multiflora rose and Oriental high moisture content. bittersweet (Celastrus orbiculatus). Herbaceous layer is sparse but includes broom-sedge (Andropogon virginicus), common reed, and switchgrass (Panicum virgatum).

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Natural Processes Responsible for HMP Broad DE WAP Limiting Factors / Threats Habitat Attributes1,2 Habitat Conditions or Wildlife Habitat Type1 Community2 Specific to Habitat1,2 Populations1,2

Upland Forest Basic Mesic Tuliptree dominates the canopy and is associated Develop on moist, nutrient rich soils with a Pollution from adjacent land uses, Forest by red maple, sweetgum, and northern red oak. near neutral or basic Ph. Associated with creation of “island” effect by adjacent The understory contains black cherry, spicebush, mafic substrates that weather to produce high development, lack of canopy species flowering dogwood and American holly. Sweet soil concentrations of magnesium. regeneration, invasive species, pepperbush (Clethra alnifolia), highbush Distinguished by a dominance of tuliptree in climate change, subsidence, deer blueberry, smooth blackhaw (Viburnum the canopy and a rich, diverse herbaceous browse. prunifolium), common greenbrier, and poison layer. Because of the low density of ivy can be found in the shrub and vine layers. overstory saplings found within this Less than 200 acres of high quality Herbaceous plants include woodland sedge community on the refuge (tuliptree and Basic Mesic Forest is mapped by DE (Carex blanda), lax-culmed sedge (Carex mockernut hickory observed only), this is WAP within the entire state of laxiculmis), sensitive fern (Onoclea sensibilis), believed to be the climax community Delaware. Christmas fern (Polystichum acrostichoides), condition. Southern grapefern (Sceptridium biternatum), New York fern, cinnamon fern (Osmunda cinnamomea), rattlesnake fern (Botrypus virginianus), Northern lady fern (Athyrium filix- femina), false nettle, narrowleaf springbeauty (Claytonia virginica), American hog-peanut (Amphicarpaea bracteata), Jack-in-the-pulpit (Arisaema triphyllum), wild yam (Dioscorea villosa), and common blue violet.

Forested Coastal Plain Low elevation forests on the refuge are typically Occurs in the Delmarva Peninsula on mineral Pollution from adjacent land uses, Wetland Flatwood and dominated by sweetgum and red maple, but are soils overlain by variable organic but non- creation of “island” effect by adjacent Depression also associated with swamp white oak (Quercus peaty layer in groundwater-influenced development, invasive species, Swamp bicolor), swamp chestnut oak (Quercus depressions and along streams and rivers. On climate change, sea level rise, michauxii), green ash (Fraxinus pennsylvanica) the refuge, located on poorly drained sand subsidence, and groundwater water and black gum (Nyssa sylvatica) in the canopy. over a high water table. Often located on flat withdrawal. Understory species include black gum, American interfluvial areas and low places. holly, mockernut hickory, and sweetbay Distinguished by swamp chestnut oak and (Magnolia virginica). Common shrubs include swamp white oak. sweet pepperbush, highbush blueberry, and arrow-wood. Greenbrier makes up the vine layer. Ground pine (Lycopodium obscurum), royal fern (Osmunda regalis), netted chain fern (Woodwardia areolata), Virginia chain fern (Woodwardia virginica), and New York fern are common herbs noted in this community.

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Natural Processes Responsible for HMP Broad DE WAP Limiting Factors / Threats Habitat Attributes1,2 Habitat Conditions or Wildlife Habitat Type1 Community2 Specific to Habitat1,2 Populations1,2

Forested Maritime Forest Canopy species include black cherry, red maple Forest and shrubland mosaic encompassing a Pollution from adjacent land uses, Wetland and sweetgum. Eastern red cedar (Juniperus range of woody vegetation defined by creation of “island” effect by adjacent virginiana), pin oak (Quercus palustris), proximity to the maritime environment. development, maritime derived persimmon, sassafras and smaller members of Includes upland and embedded wetland pollutants, invasive species, climate the canopy make up the understory. Southern environments over varying groundwater change, sea level rise, subsidence, bayberry is a common shrub while Japanese levels. Subject to common maritime stresses and groundwater water withdrawal. honeysuckle and common greenbrier are including salt spray, high winds, and common vines. brackish water inundation during storm tides. Distinguished by a dominance of wild black cherry in the canopy and occasionally eastern red cedar in the understory.

Seasonally- Impoundment Managed wetlands with fluctuating water levels. Human modified and managed wetland Pollution from adjacent land uses, managed Vegetation includes fall panic grass, wild millet, habitats where levees, water-control creation of “island” effect by adjacent Freshwater beggarticks, spikerushes, bulrushes, sprangletop, structures, and other anthropogenic landscape development, invasive species, Impoundments sedges, common reed, and cattail. alterations have been performed to restrict, climate change, sea level rise, retain, or exclude water. Water levels are subsidence, changes in salinity, and manipulated seasonally to benefit particular levee failure. species or particular needs.

Semi- Emergent Predominantly wide-leaved cattail (Typha Located in non-tidal wetland with a variety Pollution from adjacent land uses, permanent Freshwater latifolia) or common reed. Duckweed (Lemna of substrates. The wide-leaved cattail is creation of “island” effect by adjacent Freshwater Marsh spp.) can be found on the water’s surface. This located just upstream of a semi-permanent development, invasive species, Wetland habitat can be found on the refuge both within, impoundment and water levels are artificially climate change, subsidence, and and outside of, impoundments. maintained. Common reed is located in wet water groundwater withdrawal. areas where there has been previous disturbance.

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Natural Processes Responsible for HMP Broad DE WAP Limiting Factors / Threats Habitat Attributes1,2 Habitat Conditions or Wildlife Habitat Type1 Community2 Specific to Habitat1,2 Populations1,2

Semi- Freshwater One area of this community is dominated by This community is distinguished by swamp Pollution from adjacent land uses, permanent Shrub Swamp dense tangles of swamp loosestrife (Decodon loosestrife found on saturated peat in shallow creation of “island” effect by adjacent Freshwater verticillata). Herbs growing within the swamp areas at the edges of ponds and development, invasive species, Wetland loosestrife include floating spadderdock (Nuphar impoundments. This habitat is primarily climate change, levee failure, water lutea spp. variegata), waterlily (Nymphaea located in an impoundment of Finis Branch. level fluctuation. odorata), arrow-arum (Peltandra virginica) and This impoundment is controlled by a levee pickerelweed (Pontederia cordata). and water levels are generally weather dependent, with minimal artificial Another area of this community is dominated by intervention. a canopy of red maple and shrub canopy of buttonbush. Additional species within the shrub The area of this community distinguished by and vine layer include swamp rose, winterberry (Ilex verticillata), swamp loosestrife, common red maple and buttonbush is located on greenbrier and wisteria (Wisteria sinensis). saturated peat with hummock and hollow topography. In the western portion of this Herbs include sensitive fern, featherfoil area, the water is shallower and the trees are (Hottonia inflata), arrow-leaf tearthumb taller. Towards the eastern end where water (Polygonum arifolium), American bugleweed is deeper, the trees are stunted. (Lycopus americanus), arrow-arum, and pickerelweed.

Early Early Fields dominated by cool-season grasses. Located in old fields that have been Pollution from adjacent land uses, Successional Successional Common species include red fescue (Festuca abandoned or pasture. Community is creation of “island” effect by adjacent Upland Herbaceous rubra), red clover (Trifolium pratense), Queen managed with periodic mowing. development, invasive species, Anne’s lace (Daucus carota), sweet vernal grass climate change, woody species (Anthoxanthum odoratum), and orchard grass encroachment / succession. (Dactylis glomerata).

Early Early Successional areas dominated by early Often associated with disturbance and/or Pollution from adjacent land uses, Successional Successional successional tree and shrub species. This abandonment of historic agricultural areas. creation of “island” effect by adjacent Upland Shrubland community often results from disturbance or Located in abandoned agricultural fields, old development, invasive species, exotic species invasions within abandoned fields, and roadsides. climate change, and forest succession. agricultural fields or roadsides. Early successional shrublands will often succeed early successional herbaceous habitats if woody species are not controlled.

1 Bombay Hook NWR Staff observations and historic refuge accounts / surveys / datasets 2 Delaware Wildlife Action Plan, 2015-2025 (DE WAP) (DNREC 2015)

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PRIORITY RESOURCES OF CONCERN Priority Resources of Concern Selection The comprehensive ROC list (Appendix B) lists species with a broad array of habitat needs and was generated as a subset of resources of concern identified in the DE WAP and the USFWS Northeast Region list of at-risk species that are known to occur on the refuge. This initial list of over 650 species was then refined and reduced to identify priority ROC representing the spectrum of habitat needs for species at the refuge. Priority ROC were selected using the Service’s Identifying Refuge Resources of Concern Handbook (the Handbook) (Taylor and Paveglio 2017), as well as aspects of Strategic Habitat Conservation (SHC), which is an iterative process developed by the Service to support strategic decisions on habitat conservation for species on landscape-level scales (USFWS 2008). The selection process outlined within the Handbook and SHC guidance uses a focal resource concept (i.e., representative and indicator species approaches). The Handbook guides the selection of refuge priority ROC by considering which resources best address relevance to legal mandates, management significance, and ecological significance. The team also used the Resources of Concern Selection Tool for America’s Refuges (ROCSTAR) (Salas and Pranckus 2015) to help identify and quantify the relevance of individual species on the comprehensive ROC list. The ROCSTAR tool was developed to assist NWRs, waterfowl production areas, wetland management districts, and other conservation lands in identifying important resources for management and monitoring. This tool assists managers and planners in completing the selection process outlined within the Handbook. The ROCSTAR tool allows the planning team to review the applicable filters required when considering refuge priority ROC selection. It provides a decision support framework that allows users to compare various resources and their ability to address the selection considerations outlined in the Handbook (Taylor and Paveglio 2017) and incorporates aspects of the surrogate species concept as described in Caro (2010) and USFWS (2012). The tool results in a series of resource scorings sorted by habitat type. Based on the scoring results, we then made an informed decision on the number and type of Bombay Hook NWR priority ROC to select for each habitat type managed. Relevance to Legal Mandates We evaluated candidate ROC for their ability to be managed to fulfill the purposes of Bombay Hook NWR and associated Service policies and mandates. Specifically: • Contribution to Bombay Hook NWR purposes – Achieving the purposes for which the Bombay Hook NWR was established, and managing for Service trust resources and BIDEH, can be addressed through habitat requirements of focal species, i.e., species that may represent guilds that are associated with important attributes or conditions within habitat types. The use of focal species is particularly valuable in addressing Service trust resources, such as migratory birds and threatened and endangered species. By selecting focal species, we can document the Bombay Hook NWR-specific contribution to migratory bird conservation and the recovery of federally listed species. • Contribution to Refuge System – Conservation of Bombay Hook NWR focal species has an important role in supporting the long-term mission of the NWRS. By selecting focal species that can be used as a measure of management success, and developing an inventory and monitoring program around these species, the refuge can more efficiently evaluate and communicate management successes and challenges with others. Conservation and Management Significance We then evaluated candidate ROC for their management significance to the refuge. A species was considered significant to refuge management if it had the following characteristics:

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1) Management and protection of the species or its habitat is recognized as important (e.g., presence in regional conservation plans and lists noted previously) by managers, researchers, policy makers, and the public. 2) The species has a direct application to key management decisions or effectiveness of past management activities. 3) The species relies on habitat and/or population management to provide suitable or improved conditions. Evaluating management significance is important because data on the species and its habitats can help inform management decisions and progress toward refuge goals. Specifically, • Recognized need for management and protection of the priority ROC – Chapter 1 highlighted numerous national, regional, and state conservation plans used to identify conservation priorities for the refuge. Some species that ranked high on conservation plans but were only incidental or did not occur on the refuge were not included in the priority ROC selection as it was presumed that they could not be effectively managed for substantial benefit.

Additional consideration was given to Species of Greatest Conservation Need (SCGN) that are further developed in a Delaware specific Tiered system in the DE WAP. According to the DE WAP rankings Tier 1 species are in the highest need of conservation action, the rarest species in the state, globally imperiled, and regionally important populations. Tier 2 species are of moderate conservation concern, have rare to uncommon breeding populations in the state, globally broad distributions threatened by climate change, and species for which Delaware has a high responsibility within the region. Tier 3 species are common in Delaware, but are otherwise listed as SGCN for various reasons in other regional/national plans.

• Habitat requirements of priority ROC – Habitat suitability and availability may limit the capability of Bombay Hook NWR to support or manage for a priority ROC. We evaluated the following species-specific factors: 1) Historic habitat use and abundance on the refuge; 2) Habitat connectivity and species utilization of habitat types; 3) Environmental conditions including soils, hydrology, disturbance patterns, contaminants, predation, and invasive species; and 4) Specific life history needs; such as habitat needs for breeding, migrating, and overwintering stages of avian species. • Habitat management for selected priority ROC – Observations and institutional knowledge of refuge personnel was used to determine the feasibility for the refuge to support a particular species throughout specific seasons (e.g., breeding, migration, overwintering). • Ability to inform inventory and monitoring – Candidate ROC and/or their habitats were evaluated in their ability to be measured (i.e., Inventory and Monitoring Plan) and to help determine if the management objectives have could be met. Ideally, priority ROC should be present in detectable numbers, directly responsive to management actions, and relatively easy to measure.

Ecological and Landscape Significance Last, we evaluated the candidate ROC through a series of planning team meetings and literature reviews for their ecological significance to the refuge. Ecological significance is defined as a species with the following characteristics:

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1) A strong, defensible link to overall ecological function of the landscape or strongly associated with a critical resource of Bombay Hook NWR. 2) Sensitive to larger landscape or habitat changes so that it can act as an indicator of potential change. 3) Status of the species or its habitat is representative of other candidate ROC, ecological processes, or biological organizations. Evaluating the ecological significance of candidate ROC helps ensure that management and monitoring activities associated with final priority ROC, and their associated habitat requirements, contribute to refuge BIDEH. Priority ROC can be used as an indicator of BIDEH based on their presence, absence, abundance, or relative well-being in a given habitat niche. By selecting a priority ROC that represents a suite of candidate ROC species and their individual habitat requirements, the selected species can serve as a marker of the overall health of its required habitat type. We refined the list of candidate ROC during the development of the HMP, based on continued review of these criteria. Using this process, we selected 16 priority ROC including 12 birds, one amphibian, one reptile, one mammal, and one insect. (Table 3-2).

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Table 3-2 Habitat Requirements for Bombay Hook NWR Priority Resources of Concern

Priority ROC HMP Broad Patch (Source of life history Habitat Structure Special Considerations Habitat Type Size information)

Atlantic flyway population exceeds management Migrants use estuarine wetlands, tidal flats, shallow goals, but continental population has declined to freshwater wetlands, and impoundments containing American Black Duck half of its historic size. Contributors to its decline cordgrasses (Spartina spp.). Overwinters exclusively in tidal (Anas rubripes) include pesticides, contaminants, disturbance of habitats on east coast. Nesting occurs in diverse habitats Variable nest sites, and habitat loss or degradation. In mid- including salt marsh and impoundments. Brooding occurs in (Longcore et al. 2000) Atlantic region, salt marsh and tidal habitats are brackish marshes along the Atlantic coast, preferring fertile considered essential for species, especially at night wetlands but will also use acidic and low fertility wetlands and when ice forms. Preferred nesting habitat on Atlantic coast is low salt marsh dominated by cordgrasses and glassworts that had salinity of >7,100 ppm at low tide and >5,600 ppm at high tide. Clapper Rail Preferred marshes contain scattered shrubs and emergent Populations appear to be relatively stable at this (Rallus crepitans) Tidal Salt Marsh vegetation within 15 meters of open water and at least 25 time. Some potential contributors to population N/A percent total wetland area within 15 meters of shoreline. decline include pesticides, contaminants, collisions, (Rush et al. 2018) Vegetation preferred includes short- and tall-form smooth and habitat loss or degradation. cordgrass. Few individuals use salt meadow cordgrass. Little information is known on migration habitat, but presumed to use salt marsh and other habitat similar to nesting sites. Habitat is restricted to tidal salt marsh annually. Nests in the high marsh zone dominated by salt meadow cordgrass, Saltmarsh Sparrow Undergoing steep annual population decline of 9 seashore saltgrass, and black-grass rush. Will also nest in low (Ammodramus percent and highest priority species in BCR 30. marsh in smooth cordgrass when 0.4 to 1 meter in height. caudacutus) >250 ac Studies suggest sea level rise could cause Will use dense common reed for cover when disturbed. extinction in as little as 40 years. Indicator for high Breeding density and presence is positively related to marsh (Greenlaw et al. 2018) marsh quality. size, distance from upland edges, and deep layers of persistent thatch. Population numbers are generally small locally, but likely the most widespread maritime shorebird Sanderling wintering in North America. Potential contributors (Calidris alba) During migration and overwintering uses sandy beaches, to population decline include pesticides, Beach particularly hard-packed sand. During migration may also use N/A contaminants, disturbance of nest sites, reduction in (Macwhirter et al. tidal mudflats and inland margins of open water habitat. major food sources on migration (especially 2002) horseshoe-crab eggs), and habitat degradation or degradation.

3.0 Resources of Concern 3-12 August 2020 Habitat Management Plan for Bombay Hook National Wildlife Refuge

Priority ROC HMP Broad Patch (Source of life history Habitat Structure Special Considerations Habitat Type Size information)

Wide range of forested and semi-forested areas. Specific Species is highly migratory and has a large range. Eastern Red Bat requirements include shaggy bark, cavities, or crevices for Population size is assumed large, but substantially (Lasiurus borealis) roosting; an open understory for easy ingress and egress from >170 ac declining. The largest threat to species is wind

roost; and proximity to a reliable water source. Roost sites turbine impact mortality compounded by a (Natureserve, 2018) located minimum of 50 meters from forest edges. relatively low reproductive rate. Upland Forest Nesting occurs within interior and edges of deciduous and Wood Thrush mixed forest with trees greater than 16 meters in height, a Mostly considered stable, however populations are (Hylocichla mustelina) high variety of species, moderate shrub density, and an open affected by fragmentation. Contributors to potential forest floor with moist soil and decaying leaf litter. Prefers >50 ac decline include pesticides, contaminants, collisions, (Evans et al. 2011) larger area forest but may nest in 2.5 acres or greater disturbance of nest sites, and habitat loss or (Jones et al. 2001) fragmented areas. Migration habitat is poorly documented but degradation. likely uses second-growth and edge habitat containing fruit. Nesting occurs in undisturbed mature beech-maple and oak- Acadian Flycatcher hickory deciduous forests along streams or within floodplains Considered globally secure, however potential (Empidonax virescens) and swamps. On the refuge, it uses ephemeral and smaller threats involve the degradation of habitat and >50 ac forested wetlands. During migration, it is found in habitats habitat fragmentation. Considered an area- (Allen et al. 2017) that are more open or young second-growth forest, as well as dependent species. (Jones et al. 2001) Forested nesting habitat. Wetland Widespread in North America, but local Habitat is various, including forested wetlands, herbaceous Wood Frog populations declining due to residential wetlands, riparian areas, and vernal pools. Eggs are laid in (Lithobates sylvaticus) development, agriculture, and timber harvest. Good fish-free temporary or permanent open water. During winter N/A indicator of environmental health. Adults able to species can be found in or under logs, humus and leaf litter, (Natureserve 2018) assess potential breeding sites for presence of fish or under rocks. and will change sites accordingly. During migration and overwintering, uses a wide variety of Populations thought to be stable. Potential Greater Yellowlegs habitats including salt marsh, mudflat, open water, seasonal Seasonally- contributors to decline include pesticides, (Tringa melanoleuca) wetlands, and grassy meadows. Most common on tidal flats, managed N/A contaminants, disturbance of nest sites, and habitat shallow impoundments, and pools on high salt marsh in Impoundments loss or degradation, especially nonbreeding (Elphick et al. 1998) coastal areas. Will utilize taller vegetation than other (staging) and wintering grounds. shorebirds.

3.0 Resources of Concern 3-13 August 2020 Habitat Management Plan for Bombay Hook National Wildlife Refuge

Priority ROC HMP Broad Patch (Source of life history Habitat Structure Special Considerations Habitat Type Size information)

During migration uses various estuarine and riverine Not endangered but populations are lower than wetlands. During spring utilizes marshes, mud flats, tidal desired. In 2002, breeding populations reached Northern Pintail pools and brackish ponds. During fall prefers emergent and their lowest level since surveys began in 1955. (Anas acuta) submersed vegetation communities with floating sedge mats. N/A Contributors to its decline include pesticides, Migrant occupancy is positively correlated with abundant contaminants, disturbance of nest sites, collisions, (Clark et al. 2014) moist-soil foods and shallow water levels. Overwintering and habitat loss or degradation of breeding and habitat includes large shallow wetlands with minimal cover wintering grounds. with areas of dense vegetation for nocturnal cover.

Semipalmated Habitat during migration is shallow fresh or salt water with Significant population declines have been observed Sandpiper little vegetation, muddy intertidal zones, or along edges of at migration staging areas. The Delaware Bay has (Calidris pusilla) open water. Substrate is typically soft silt or clay. During fall, N/A been identified as a “Hemispheric Site” of great roost in large numbers in exposed areas during high tide importance by the Shorebird Reserve Network as a (Hicklin et al. 2010) when saltmarsh is flooded. spring staging area.

Nesting on the Atlantic coast occurs in marshes with tall, dense growths of bulrush and cattail with peak water depths Little population data exists, as species is secretive Least Bittern of 70 centimeters. Often associated with tall, dense and difficult to monitor. Populations appear stable, (Ixobrychus exilis) vegetation over stable water levels at managed but too little data exists to assess North American >25 ac impoundments. Avoids open mudflat or sparse or short populations accurately. Preservation, protection, (Poole et al. 2009) vegetation. Nests sites average 3.5 meters from open water. and improvement of large (>25 ac) wetland habitat Migration habitat is similar to nesting habitat though less is the most urgent conservation need. Semi-permanent dense vegetation and shallower water may be tolerated. Freshwater Wetland Habitat includes shallow bodies of water with soft bottoms and emergent vegetation. Community hibernacula are located This species is currently under review by USFWS in muddy bottoms of wetlands and waterways with water Spotted Turtle for protection under the Endangered Species Act. depths of 55 to 95 centimeters. Post hibernation, species (Clemmys guttata) Little information is known about current moves to vernal pools for 3 to 4 months, then to secluded N/A population trends, but widely distributed in eastern uplands for up to 2 weeks, and then finally back to wetland (Natureserve 2018) North America. Locally common, but declining in habitat. Eggs are laid in well-drained soils, in hummocks or some areas due to habitat loss and fragmentation. open areas with solar exposure, at the edge of thick vegetation.

3.0 Resources of Concern 3-14 August 2020 Habitat Management Plan for Bombay Hook National Wildlife Refuge

Priority ROC HMP Broad Patch (Source of life history Habitat Structure Special Considerations Habitat Type Size information)

Habitat includes a variety of early successional vegetation types including agricultural fields, grasslands, grass-brush Northern Bobwhite Populations have declined an average of 3 percent rangelands, and mixed pine-hardwood forests. Nests are Quail per year since 1966 at the continental scale and 6 located in basketball-sized clumps of bunchgrasses with an (Colinus virginianus) percent per year since 1996 in the Mid-Atlantic due optimal density of 600 to 700 clumps per acre. Loafing >10 ac to habitat loss. Presence of exotic grasses and and/or escape cover required includes shrubs 3 to 10 feet tall (Brennan et al. 2014) herbicide use can diminish usable habitat by and a minimum of 5-feet in diameter covering 10 to 30 (Palmer et al. 2011) reducing native forb and arthropod densities. percent of the landscape. Woody cover is essential to keep snow off ground during winter.

Monarch butterflies are on the decline due to shifting land management practices and loss of its Monarch Butterfly Occupies open fields and meadows with milkweeds essential larval specific host plant, milkweed. (Danaus plexippus) Early (Asclepias spp.) in the spring and summer. Habitat in the These species are also vulnerable to pesticides used Successional Delaware Bay is considered important regional habitat during N/A for control of mosquitoes and other widespread Upland migration as the species may holdover for several days problem insects. This species is currently under awaiting suitable conditions before crossing the bay. (Natureserve 2018) review by the USFWS for protection under the Endangered Species Act.

Range-wide populations have declined between 1.2 percent and 2.2 percent per year according to Nesting habitat on the Atlantic coast is open country, breeding bird surveys and Christmas bird counts, especially thickets and scrubby fields with hawthorns respectively. Loss of shrub habitat to forest Brown Thrasher (Crataegus spp.). Elsewhere in the eastern United States it succession or agriculture is believed to be the cause (Toxostoma rufum) can be found in riparian woodlands, woody draws, thickets, >10 ac of the decline, but species may be also be sensitive

and shelterbelts. Rare in woodlots <10 acres. During to habitat fragmentation. In areas surveyed the year (Cavitt et al. 2014) migration a variety of habitat with fruit bearing plants following emergence of periodical cicadas including hedgerows, rights-of-way, and forest. (Magicicada spp.), populations increased significantly and then stabilized, suggesting food supply may be a limiting factor.

3.0 Resources of Concern 3-15 August 2020

Bombay Hook NWR Priority ROC Species and Relation to Refuge BIDEH Coastal Habitats We selected American black duck, clapper rail, and saltmarsh sparrow as ROCs for the refuge’s tidal salt marsh. Collectively, these three species indicate the overall habitat suitability for all seasons throughout the year and all vegetation strata. All three species are ranked as Tier 1 DE WAP species, PIF BCD 30 priority species, NALCC representative species, and USFWS Migratory Bird Program birds of management concern. American black ducks act as a focal species for other waterfowl that require freshwater emergent wetlands and salt marsh habitat for migratory stopover and overwintering. Clapper rails represent other migratory and breeding birds in low marsh areas of the refuge. Salt marsh sparrows serve as indicators for high marsh quality and ecological integrity, and are a year-round resident of the refuge. This a USFWS at-risk species. The sanderling was chosen as the sole ROC for our limited beach habitat. It is a Tier 1 DE WAP species, a PIF BRR 30 priority species, a NALCCC representative species, and a USFWS Migratory Bird Program bird of management concern. Our ability to conduct any monitoring of this lower priority habitat is expected to be limited. Sanderlings utilize sandy beach habitats, especially during winter. The refuge beach habitat would generally not be extensive enough to support breeding of beach-nesting birds. Forested Habitats For the refuge’s upland forest, we selected the eastern red bad and wood thrush as ROCs because both species use a variety of forested habitats and are sensitive to forest area and patch size. The wood thrush is a Tier 2 DE WAP species, a PIF BCR 30 priority species, a NALCC representative species, and a USFWS Migratory Bird Program bird of management concern. It is considered representative of other forest-obligate landbirds that use refuge forests for migration and breeding. The eastern red bat is a Tier 3 DE WAP species, and a NALCC representative species. Red bat represents tree roosting bats, are indicative of presence of mature forest suitable for roosting, foraging, and breeding, and are representative of migratory and nesting habitat for bird species. We selected Acadian flycatcher and wood frog as ROCs for the refuge’s forested wetlands to represent the diverse taxa groups that utilize this habitat on the refuge. The Acadian flycatcher breeds on the refuge, and is ranked as a Tier 3 DE WAP species and a USFWS Migratory Bird Program bird of management concern, Increased, or sustained, population numbers of Acadian flycatcher is expected to result from increased acreages of forested wetland habitat that also benefit other refuge ROC. Wood frog is a year- round resident of the refuge, a Tier 3 DE WAP species, and a NALCC representative species. Wood frogs are sensitive to loss of forest, and its population increases or declines are indicative of associated habitat quality or abundance available to other herpifauna. Freshwater Wetland Habitats For the refuge’s seasonally managed freshwater impoundments, we selected greater yellowlegs, northern pintail, and semipalmated sandpiper as ROCs. All three are PIF BCR 30 priority species and USFWS Migratory Bird Program birds of management concern. Collectively these species represent the various habitat conditions that result from impoundment management, and their presence and population fluctuations can be used to gauge effectiveness of annual water level manipulations. Greater yellowlegs is a Tier 1 DE WAP species that uses the refuge impoundments primarily during spring and fall migration. Northern pintail is a dabbling duck that uses the shallow water in the impoundments to feed on flooded vegetation. It is also a Tier 2 DE WAP species and a NALCC representative species. Semipalmated sandpiper is a common shorebird on the refuge during migration, utilizing exposed mudflats and very shallow water. It is a Tier 1 DE WAP species and a NALCC representative species. The refuge’s semi-permanent freshwater wetland habitat is represented by least bittern and spotted turtle, because they both are NALCC representative species that breed on the refuge and use a variety of freshwater wetland habitats. Least bittern is also a Tier 2 DE WAP species, a PIF BCR 30 priority

3.0 Resources of Concern 3-16 August 2020

species, and a USFWS Migratory Bird Program bird of management concern. On the refuge, they are representative of marsh bird breeding, foraging, and migratory habitat. Spotted turtle is a Tier 1 DE WAP species and a USFWS at-risk species that lives on the refuge year round. It is indicative of semi- permanent open water and can be associated with other non-bird species that require this freshwater habitat. Early Successional Habitats We selected northern bobwhite quail, monarch butterfly, and brown thrasher as ROCs for the refuge’s early successional habitat. Collectively, these species represent diverse taxa groups and various types of early successional (grassland and shrubland) habitats that occur on the refuge, and their use of these habitats represents all seasons. Northern bobwhite quail is a year-round resident on the refuge, a Tier 2 DE WAP species, and a PIF BCR 30 priority species. On the refuge, northern bobwhite quail represents breeding and migrating landbirds that require open grassland habitat with limited woody species encroachment. Monarch butterfly is a Tier 1 DE WAP species that breeds and migrates on the refuge. As a common and easily identifiable butterfly, it is considered a flagship species indicating the relative health of grasslands (sustaining mixed forb cover) and representative of other invertebrate pollinator species. Brown thrasher is year-round resident on the refuge, ranked as a Tier 3 DE WAP species, a PIF BCR 30 priority species, a NALCC representative species, and a USFWS Migratory Bird Program Bird of Management Concern. It utilizes the shrubby habitat that occurs in forest clearings and edges, fencerows, shelterbelts and fields. Together, these species are indicative of successful early successional upland management and/or restoration limiting wooding species encroachment. Table 3-3 summarizes the life history and refuge use for each of the Bombay Hook NWR priority ROC. It also notes other species of conservation concern that would benefit from management for priority ROC.

3.0 Resources of Concern 3-17 August 2020

Table 3-3 Priority ROC and Other Benefiting Candidate ROC at Bombay Hook NWR Life HMP Broad Priority History Habitat Other Benefitting Candidate ROC ROC on Type Refuge1 • Marsh Wren • Black-crowned Night-heron American Y Black Duck • Seaside Sparrow • Fiddler Crab • Willet • Atlantic Silverside Tidal Salt • Black Rail • Mummichog Clapper Rail B, M Marsh • Swamp Sparrow • Northern Harrier • Snowy Egret • Glossy Ibis Saltmarsh • • Y American Eel Forster’s Tern Sparrow • Northern Diamond-backed Terrapin • Short-eared Owl

• Black Skimmer • Ruddy Turnstone Sanderling W Beach • Red Knot • Black-bellied Plover • Red-shouldered Hawk • Little Brown Bat Eastern Red • • B, M, W Black-and-white Warbler Yellow-throated Vireo Bat • Scarlet Tanager • Hooded Warbler • Worm-eating Warbler • Bald Eagle Upland Forest • Northern Flicker • Eastern Box Turtle • Great Crested Flycatcher • Baltimore Oriole Wood Thrush B, M • Cope’s Gray Treefrog • Cerulean Warbler • Brown Creeper • Northern Long-eared Bat Acadian B, M • Prothonotary Warbler Flycatcher • Tiger Salamander Forested • Spotted Salamander • Northern Parula Wetland • Marbled Salamander • Swainson’s Warbler Wood Frog Y • New Jersey Chorus Frog

Greater M, W • Mallard Yellowlegs • Short-billed Dowitcher Seasonally • Atlantic Coast Leopard Frog managed • American Avocet Northern • Green-winged Teal M, W Freshwater • Ruddy Duck Pintail • Great Egret Impoundments • Black-necked Stilt • Dunlin Semipalmated • Marbled Godwit M • Sandpiper American Wigeon

Least Bittern B, M Semi- • American Bittern permanent • Northern Red-bellied Cooter • Virginia Rail Freshwater • Northern Cricket Frog Spotted Turtle Y Wetland • Sora

Northern Y • Field Sparrow • Eastern Towhee Bobwhite • Eastern Meadowlark • Yellow-breasted Chat Early Monarch • Fowler’s Toad • Prairie Warbler B, M Successional Butterfly • • Upland Bobolink Grasshopper Sparrow Brown • Savannah Sparrow • American Kestrel Y Thrasher • Northern American Least Shrew

1 B = breeding; M = migration; Y = year-round resident; W = wintering

3.0 Resources of Concern 3-18 August 2020

PRIORITY HABITATS Maintaining quality habitat requires long-term dedication of resources. Managing with limited resources requires prioritization to ensure the most important resource needs are met. We prioritized the habitat types within the refuge based on current condition, availability within the landscape, management need and capability, plus conservation needs of priority ROC. Because personnel and funding resources are limited, our management activities are primarily directed toward habitat management that can have the greatest contribution to ROC, protecting existing high quality habitats, and restoring biological diversity or habitat structure where able. For the purposes of habitat management, we categorized habitat types on the refuge into seven broad habitat types (detailed in Table 2-2): • Tidal Salt Marsh • Beach • Upland Forest • Forested Wetland • Seasonally managed Freshwater Impoundments • Semi-permanent Freshwater Wetland • Early Successional Upland We presented an overview of these habitats, as well as their priority for management, and how they benefit Bombay Hook NWR priority ROC in Table 3-4. Tiers of priority habitats are broadly defined in the ROC Handbook (Taylor and Paveglio 2017). Tier 1 of highest priority habitats demonstrate the one or more of following attributes: • Can be managed to provide the greatest conservation benefit to priority ROC, especially those specifically identified in the refuge purpose.

• Offer the greatest contribution to maintenance/restoration of BIDEH, represent important ecological and ecosystem processes not well represented within the landscape (including the broader ecoregion of which the refuge/district is a part), and address conservation needs of the NWR resources of concern.

• Habitat condition or other factors suggest an urgent need for active management. Tier 2 of lower priority habitats demonstrate one or more of the following attributes: • Too limited in extent to make a meaningful difference.

• Outside the management authority or jurisdiction of the refuge/district.

• Do not require active management to maintain their present condition. Although a habitat may be ranked as lower priority, this should not be interpreted to mean that this habitat type does not provide valuable habitat to a variety of species and contribute to the overall diversity of the refuge. In many cases, these habitats do not require active management by the Refuge or they represent an area where we have little management capability. Within each tier, the planning team has further identified priority ranks for each broad habitat type. Again, these rankings reflect a combination of relative importance on the regional landscape, the ability of the refuge to manage the habitat effectively, and the amount of effort necessary to do so.

3.0 Resources of Concern 3-19 August 2020

Given the Refuge System diverse goals, purposes, mandates, and conservation priorities, it is not uncommon for a refuge to have conflicting management options, such as situations where multiple management strategies are mutually exclusive. Balancing the types, proportion, and specific location of habitats (and their management) requires special consideration and a process for determining the best course of action. Some habitat management decisions at Bombay Hook NWR require such consideration. The potential to manage refuge habitats differently than we have in the past is the foundation for the purpose and need to prepare an environmental assessment with this HMP. The environmental assessment (EA; appendix A) presents two alternatives for habitat management direction and an analysis of the potential impacts that would result from fully implementing either of the alternatives over the next 15 years. Table 3-4 Priority Habitats at Bombay Hook NWR

Priority Management Considerations Habitat Reasons for Priority Ranking Rank

Tier 1 Habitats • Location of forests provides management capability to Restoration of this habitat will be a positively influence habitat and ROC. priority in areas where natural Forested Wetland 1 hydrology had been altered, and • Forests are one of the most imperiled habitats in the where hydric soils exist Delmarva Peninsula. • Refuge upland forest represent potential for high Restoration of this habitat will be a quality habitat identified by DE WAP as priority in areas where existing underrepresented in Delmarva Peninsula. forested patches exist in the adjacent landscape, and can become connected Upland Forest 2 • Location of forests provides management capability to to form larger forest patches positively influence habitat and ROC.

• Forests are one of the most imperiled habitats in the Delmarva Peninsula. In the long term (15 years), it will become more difficult to manage the impoundments due to global climate • Active management of this habitat requires frequent change effects. Increasing sea level monitoring and changes to water control structures. Seasonally- rise will reduce our potential to Current staff capabilities allow for this frequent yet managed manage water levels, because 3 low-effort active management. Freshwater drawdowns must occur when the

Impoundments tidal marsh water level is lower than • Supports a wide variety of refuge ROC during all that in the impoundment. As sea seasons. level rises, the threat of impoundment breaches and saltwater intrusion increases • Largest acreage of all refuge habitat types. Many of the challenges this habitat faces are difficult to contend with • Supports a wide variety of refuge ROC during all through refuge management, and it seasons. will continue to be difficult to curb Tidal Salt Marsh 4 marsh loss • Limited access due to logistical and safety considerations limit the ability for refuge staff to actively manage this habitat. Tier 2 Habitats

3.0 Resources of Concern 3-20 August 2020

Priority Management Considerations Habitat Reasons for Priority Ranking Rank • Often former agricultural lands in variable states of Management of these habitats will be BIDEH. a priority in areas where the adjacent landscape is open (such as privately • Open habitats can provide critical habitat for high managed croplands), the patch size is Early Successional 5 conservation priorities, such as grassland birds and relatively small, and/or there is Upland pollinators. visibility to the public for grassland wildlife viewing • Invasive species encroachment and succession require intensive maintenance with limited resources. • Supports a wide variety of refuge ROC during all Integrity and persistence of these seasons. habitats may be affected by changes Semi-permanent in precipitation patterns exacerbated Freshwater 6 • Dominance by existing invasive species monocultures by climate change Wetland limits habitat quality, but also limits management efforts required to sustain habitat. • Smallest acreage present on refuge. This habitat has experienced and will continue to be susceptible to coastal • Limited ability for active management due to logistical erosion, which may be exacerbated by Beach 7 and safety considerations. climate change

• Constant natural disturbance limits ability for refuge staff to effectively manage.

3.0 Resources of Concern 3-21 August 2020

Habitat Management Plan for Bombay Hook National Wildlife Refuge

CHAPTER 4. HABITAT GOALS, OBJECTIVES, AND MANAGEMENT STRATEGIES DEFINING HMP GOALS AND OBJECTIVES The purpose of this chapter is to provide a comprehensive view of the habitat management direction as detailed in the preferred alternative B (appendix A). Habitat Management Goals The planning team developed habitat management goals after considering the vision statement, the purposes for establishing the refuge, the missions of the Service and the Refuge System, and the mandates, plans, and conservation initiatives noted above. These goals are intentionally broad, descriptive statements of purpose. They highlight elements that we will emphasize in its future management. In developing and adopting a HMP for Bombay Hook NWR, we want to accomplish the following goals: Goal 1. Forested Habitats – Perpetuate and restore the biological integrity, diversity, and environmental health of refuge upland and wetland forests that benefit priority resources of concern. Goal 2. Freshwater Wetlands – Maintain the quality of the wetland habitats surrounding and within the refuge’s wetland impoundments, ponds, and moist soil units with seasonal management that benefit priority resources of concern. Goal 3. Coastal Salt Marsh Habitats – Perpetuate and restore the biological integrity, diversity, and environmental health of tidal salt marsh and associated tidal shrub and beach habitats to benefit priority resources of concern. Diminish marsh loss and pursue restoration, where appropriate, to ensure natural sustainability. Goal 4. Early Successional Upland Habitats – Maintain, enhance, and/or restore the vegetation, biological integrity, diversity, and environmental health of early successional habitats that benefit priority resources of concern. Habitat Management Objectives and Adaptive Management Nested under these goals, we developed objectives and strategies for each of the seven broad habitat types present throughout the refuge to identify priorities and streamline the use of resource management assets. Likewise, Service policy (601 FW 1, 3, 4) has encouraged development and application of measurable objectives to help define success in achieving management goals. Specifically objectives are to be Specific, Measurable, Achievable, Result-oriented, and Time-fixed as specified in the Service’s Writing Refuge Management Goals and Objectives: A Handbook (Adamcik et al. 2004). We developed an objectives hierarchy to help direct management resources (Figure 4-1). This hierarchy depicts the relationships among refuge purpose and goals, habitat management objectives, and measurable attributes, which are all features that tie habitat management into an adaptive management framework. Through the development of this HMP, the refuge is working towards enhancement of adaptive management and SHC principles in their delivery of on-the-ground management. Chapter 4 outlines objectives for habitat management, which will enable the refuge to evaluate their ability to provide the conditions required for priority ROC. The associated management strategies are the intended actions assigned by the planning team (including Bombay Hook NWR staff) to achieve these management objectives. Forging the Future: A Guide to Implementing Adaptive Management in the National Wildlife Refuge System (Knutson et al. 2017) provides operational guidance for implementing effective natural resource management and implementation of adaptive management within the Refuge System. Adaptive management is a structured process that goes beyond employing best management practices and monitoring the outcomes. Adaptive management is a process by which managers collaboratively evaluate

4.0 Habitat Goal, Objectives, and Management Strategies 4-1 August 2020 Habitat Management Plan for Bombay Hook National Wildlife Refuge and think about resource problems in new ways. In doing so, this process brings together scientists and managers to find and test new management solutions, and monitoring outcomes in ways that foster learning. Clear management goals and objectives, explicit documentation of actions and results, monitoring, data management, and learning and adapting are essential components of adaptive management (Knutson et al. 2017). Considerations for adaptive management have been made in preparation of the goals, objectives, and priority ROC selection developed as part of this HMP. We will continuously review and may revisit/revise goals, objectives, and priority ROC based on new information. Figure 4-1 also presents administrative objectives potentially influenced by cost and public perception. While these factors do not directly dictate habitat management actions, planning and implementation of management strategies should consider their potential influence on timing and duration of certain activities.

4.0 Habitat Goal, Objectives, and Management Strategies 4-2 August 2020 Habitat Management Plan for Bombay Hook National Wildlife Refuge

Figure 4-1. Habitat Management Objectives Hierarchy for the Bombay Hook NWR

4.0 Habitat Goal, Objectives, and Management Strategies 4-3 August 2020 Habitat Management Plan for Bombay Hook National Wildlife Refuge

The seven habitat types defined within this HMP were identified in Chapter 2 and prioritized in Chapter 3 relative to vegetation, management capability, and priority ROC conservation needs (see Sections 2.5, 2.6, 3.4, 3.5, and Table 3-4). Objectives were developed for each of these habitat types and are presented in section 4.4, each in association with the habitat management goal which it supports. Refined objectives include specific and measurable thresholds based on life history requirements of the identified priority ROC. We crafted the objectives to span the 15-year timeframe within which the HMP is anticipated to be relevant. Although objectives may be actively managed and monitored according to the supporting IMP, specific measureable metrics may be knowingly or deliberately not met on any given year. Thus, where applicable, objectives refer to annual average, ranges of values, or other thresholds within which average or “normal year” values are expected to fall. The proposed habitat conditions envisioned by the habitat management objectives outlined within this HMP are depicted in Figures 4-2 through 4-4.

4.0 Habitat Goal, Objectives, and Management Strategies 4-4 August 2020 Habitat Management Plan for Bombay Hook National Wildlife Refuge

Figure 4-2. Overview of Planned Habitat Types for Bombay Hook NWR

4.0 Habitat Goal, Objectives, and Management Strategies 4-5 August 2020 Habitat Management Plan for Bombay Hook National Wildlife Refuge

Figure 4-3. Overview of Planned Habitat Types for Bombay Hook NWR

4.0 Habitat Goal, Objectives, and Management Strategies 4-6 August 2020 Habitat Management Plan for Bombay Hook National Wildlife Refuge

Figure 4-4. Overview of Planned Habitat Types for Bombay Hook NWR

4.0 Habitat Goal, Objectives, and Management Strategies 4-7 August 2020 Habitat Management Plan for Bombay Hook National Wildlife Refuge

MANAGEMENT STRATEGIES COMMON TO ALL REFUGE HABITATS AND OBJECTIVES The following management strategies are generally common to all habitats or are landscape-scale strategies that may equally benefit all habitats and the ROC supported by the refuge. Many of these common strategies respond to threats that are not specific in their effect to any given habitat (see Section 2.12). In all cases, with input of additional resources, such as funding, partnerships, or staff, we will: • Concentrate on restoring and enhancing the biological integrity of tier I habitats by intensifying and expanding our invasive plant control efforts. Herbivory Management Strategies Controlling herbivory is important to achieve the plant composition and structure outlined within habitat objectives. Herbivory is controlled through a variety of lethal and non-lethal methods. We will select the appropriate technique based on the identified need, extent of the threat, and effectiveness of control methods such as: • Hunting and targeted removals (in accordance with the refuge Hunting Plan). • Installing exclusions or tree guards for new plantings. Human Intrusions and Disturbance Preventing non-permitted use and trespass is essential to preserving and enhancing the BIDEH of the refuge. While not a common occurrence, threats from non-consumptive human activities can alter, destroy, and disturb habitats and their associated ROC. On the refuge as a whole, we will: • Discourage non-permitted use and trespass into areas not open to public access. Invasive Species Control Strategies Although the short-term goal is to contain the extent of invasive species at 2018 levels, our long-term goal is to reduce or contain invasive species cover to be limited to less than 20 percent of the total cover of any individual management unit. The refuge conducts strategic and efficient management of invasive and other undesirable species, and we will use guidance outlined in the IPM Tool to target and control invasive plants in particular (Figure 4-5). We will accomplish invasive species control via physical, chemical, and biological treatments and with the following strategic foci: • Establishing management protocols appropriate for most problematic invasive species, and develop/adjust management strategies accordingly (using invasive management decision-tree tool).

• Immediately treating new infestations through early detection and rapid response.

• Targeting isolated populations or species with initially limited distribution.

• Prioritizing public use areas.

• Maintaining relationship with refuge working groups, private landowners, and others to control drift of invasive plants and animals from private lands.

• Supporting ongoing monitoring for emergent pests/pathogens and new infestations of known species. • Considering existing and anticipated pests and pathogens when developing or conducting supplemental plantings.

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• Continuing to use and introduce low-risk biological controls , as they become available. Climate Change Adaptation Strategies We will facilitate long-term ecosystem adaptation to the effects of climate change as well as resiliency to extreme weather conditions and intense weather events through: • Considering climate adaptation strategy specific to the refuge that is based on current projections and downscaled climate data for the Delmarva Peninsula. Climate change adaptability was considered in the preparation of each individual habitat objective in the HMP, but not for the refuge as a whole.

• Considering climate adaptation strategies such as, but not limited to, species selections included as part of supplemental planting, proactive alterations of diking systems and water control structures, and anticipated changes in salinity resulting from sea level rise.

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Figure 4-5. Strategic Management of Invasive Plants

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HABITAT MANAGEMENT OBJECTIVES, STRATEGIES, AND RATIONALES Goal 1. Forested Habitats Perpetuate and restore the biological integrity, diversity, and environmental health of refuge upland and wetland forests that benefit priority resources of concern. HMP Objective 1.1: Forested Wetland Objective Manage approximately 1,070 acres of Coastal Plain forested wetland to benefit migratory landbird foraging, resting, and breeding birds (e.g., Acadian flycatcher) and resident amphibians (e.g., wood frog). Coastal Plain forested wetlands will have the following attributes: • A contiguous mosaic of forested wetland patches (>50 acres) of varying successional stages.

• Early successional forested wetland, with a minimum stem density of 436-per-acre of fast growing native tree species (e.g., red maple, black gum) with less than 10 percent cover of invasive species.

• Mid-successional forested wetland transitioning toward mature forested wetland, with structure between 10 to 50 feet in height and up to 100 percent canopy cover of native woody species with less than 20 percent cover of invasive species.

• Mature forested wetland, with

o Canopy trees greater than 50 feet in height with more than 60 percent canopy cover.

o A canopy dominated by a minimum of 50 percent cover of oaks (Quercus spp.), with the remainder composed of a mixture of sweetgum, black gum, red maple, and other native hardwood tree species.

o A structurally diverse understory containing a mosaic of 50 percent cover of native trees and shrubs 9 to 30 feet in height, and 50 percent cover of native herbaceous groundcover or bare ground.

o Less than 20 percent cover of shade-tolerant invasive species within each mature forested wetland management unit.

• Presence of multiple isolated seasonal depressional wetlands, representing areas of short (<45 days), moderate (45-75 days), and long (>75 days) periods of flooding.

• Presence of naturally occurring coarse woody debris, as well as downed logs and snags.

Management Strategies In order of priority using existing resources, we may consider where applicable: 1. Allowing natural succession to convert former agricultural lands from grassland to early successional forested wetland habitat. 2. Plugging existing ditches to restore hydrology to adjacent lands where early successional forested wetland habitat is developing. With the contribution of additional resources (funding, staff, or partners), we will consider:

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3. Planting native tree and/or understory species to supplement plant community structural and composition diversity. 4. Conducting invasive species control applications on priority treatment areas for species such as garlic mustard (early detection against future invasion), Japanese honeysuckle, mile-a-minute, Japanese stiltgrass, multiflora rose, autumn olive, and common reed. 5. Improving forest structure by utilizing forest stand improvement techniques promoting regeneration of oak and other hardwood tree species to achieve the goal for native species composition. Rationale Prior to European settlement, most of Delaware was forested. Initial forest losses were due to conversion to agricultural land, and later due to increases in commercial and residential development. Today, approximately 29 percent of the Delaware is forested, and Kent County is experiencing some of the highest rates for forest habitat losses in the state due to commercial and residential development (DNREC 2015). Seventy-five percent of the remaining forested habitat in Delaware is privately held and subject to disturbance, fragmentation, or loss. Fragmentation due to increased development of urban communities results in habitat loss and creates habitat sinks (DNREC 2015). The perpetual protection of the refuge’s forested wetlands provides an opportunity to protect, maintain, and increase the amount of this habitat, which is limited in the Delmarva Peninsula. Delaware provides approximately 16 percent of the modeled coastal plain flatwood and depression swamp habitat, the primary forested wetland community type within the refuge, for the entire Northeast. In Delaware, 80 percent of the coastal plain flatwood and depression swamp is less than 60 years old and recovering from historic logging impacts (Anderson et al. 2013). Within the refuge, forested wetland is currently found on approximately 790 acres and makes up approximately 5 percent of the total land cover. Over time, through restoration and natural succession, the refuge would increase this total to approximately 1,070 acres, approximately 6.6 percent of the total refuge land cover. This will be an increase of approximately 275 acres as a result of converting some areas of early successional areas and upland forest to forested wetland through restoration. As the highest priority for refuge management, improving the availability and quality of forested wetland habitat within the refuge will contribute to the larger landscape with the Delmarva Peninsula. Delaware has high responsibility for this habitat in the Northeast, thus the refuge is able to make a significant contribution to conservation of this habitat in the regional landscape (DNREC 2015). In combination with upland forest, the refuge will provide a total of 1,920 acres of forested habitat. The refuge goal in relation to forested wetland is to increase the BIDEH of the habitat type itself and the variety of wildlife that rely upon this habitat, using the priority ROC as a gauge of successful restoration. On the refuge, forested wetlands provide resting and foraging opportunities for migrating landbirds, breeding habitat for forest birds such as Acadian flycatchers and mammals such as bats, and full life cycle habitat for amphibians and reptiles such as wood frogs. Collectively, these species require mature forests containing mostly closed canopy structure in sizable patches of 50 acres or more. The presence of water during a portion of the year sets these forests apart from upland forests, some of which may even have a similar tree species composition. The depth of water as well as the duration of flooding (hydroperiod) can vary based on precipitation patterns. Ideally, a fairly even distribution of areas that flood for short (<45 days), moderate (45 to 74 days) and long (>75 days) periods of time will best meet the life history needs of priority ROC associated with this habitat, as well as other benefiting species. However, the refuge has no direct ability to manage water levels in these habitats, once modifications to restore wetland hydrology (e.g., installation of ditch plugs) have been conducted. To actively restore new areas of forested wetland, the refuge will initially use earthen plugs placed in existing linear drainage ditches to restore hydrology to adjacent areas. This is a common strategy in

4.0 Habitat Goal, Objectives, and Management Strategies 4-12 August 2020 Habitat Management Plan for Bombay Hook National Wildlife Refuge habitat restoration, where past alterations to hydrology are identified and thus fairly easy to reverse. Where practicable, soils used for these earthen plugs will be excavated from nearby areas intended to be restored to forested wetland with the assumption these excavated depressions will serve as isolated shallow waters or vernal pools. Initially, tree species such as red maple and black gum that have exhibited vigorous growth and have adjusted well to changes soil biology, composition, and hydrology elsewhere on the refuge will be planted, to establish a young forested wetland. Restored areas will then be allowed to passively mature, while managing for invasive species encroachment and performing supplemental plantings as appropriate. Data about soil type, distribution of hydric soils, and elevation gradients will guide the implementation of these strategies, providing a prediction about resulting hydrology. Additional information, especially regarding the composition and structure of current refuge forested wetlands and off-site reference areas containing ideal conditions within existing mature forested wetlands, will help guide adaptive management strategies into the future as part of this objective and assess the success or restoration efforts. Information Needs The following management-related tools or additional data will help inform management decisions into the future: 1. Identification of forest reference sites to better quantify baseline and target conditions.

2. Map invasive species distribution on the refuge to develop a priority list and strategy to control the future spread or elimination of specific invasive species.

3. Conduct a forest health inventory and assessment to understand species-specific detection and response needs which will determine specific techniques required to stop or mitigate spread of disease or insect infestations, if practicable.

4. Complete an updated inventory of vegetation composition and structure to inform the location, number and type of native tree plantings.

5. Map vernal pool distribution and record amphibian use.

6. Conduct or collaborate with partners on ground water assessment/monitoring, to better understand potential impacts of off-refuge activities such as center pivot irrigation on nearby farm lands.

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HMP Objective 1.2: Upland Forest Objective Manage approximately 850 acres of upland forest to maintain the diversity of plant composition and structure required for migratory landbirds (e.g., wood thrush) and tree bats (e.g., eastern red bat). Upland forest will have the following attributes: • Approximately 615 acres of early to mid-successional forest dominated by native woody species ranging between 10 to 50 feet in height with high (60 to 100 percent) canopy cover.

• Approximately 235 acres of existing mature forest with species composition dominated by oaks and other hardwood tree species containing:

o Forest structure of greater than 50 feet in height with more than 60 percent canopy cover.

o Presence of mature trees further than 150 feet from forest edges containing extant foliage, shaggy bark, cavities, or crevices at or above 50 feet in height.

o A structurally diverse understory containing a mosaic of 50 percent cover of native trees and shrubs less than 20 feet in height and 50 percent cover of native herbaceous groundcover or bare ground.

o Contiguous upland forest patches, consisting of a combination of any forest successional stage, greater than 50 acres in size.

• Less than 20 percent cover of invasive species within each upland forest management unit. Management Strategies In order of priority using existing resources we will consider where applicable: 1. Allowing natural succession to convert early and mid-successional upland forest to mature upland forest. With the contribution of additional resources (funding, staff, or partners) we will consider: 2. Conducting invasive species control applications on priority treatment areas for garlic mustard (early detection against future invasion), Japanese honeysuckle, mile-a-minute, Japanese stiltgrass, multiflora rose, autumn olive. 3. Planting native tree and/or understory species to supplement plant community structural and composition diversity. 4. Improving forest structure promoting regeneration of oak and other hardwood tree species through appropriate silvicultural methods. Rationale Upland forests are a high priority because of their fragmentation and lack of high quality old growth forest within Delaware and the Delmarva Peninsula. Currently, approximately 5.5 percent (900 acres) of the refuge is composed of upland forest habitat. While a majority of Delaware’s upland forests are considered mature (generally comprised of trees greater than 9 inches diameter at breast height), there are little, if any, old-growth forests. The establishment of permanently protected and unharvested upland forest is necessary to ensure the development of old growth forest and the species that depend on them for large diameter trees, snags, and coarse woody debris (DNREC 2015).

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As with forested wetlands, the perpetual protection of the refuge’s upland forests provides an opportunity to protect, maintain, and increase the amount of these specific communities that are limited in Delaware and the Delmarva Peninsula. Over the life of this HMP, we would manage the refuge’s existing 235 acres of mature upland forest to maintain and enhance its quality, primarily by reducing total cover of invasive plants (e.g., highest priority species). Currently, a majority the refuge’s mature upland forest is fragmented into patches 10 acres of less. We aim to promote succession of early to mid-successional forest stands (615 acres) to mature upland forest, which will connect existing stands of forest, resulting in more large patches (>50 contiguous). As discussed in objective 1.1, we would restore 50 acres of upland forest to forested wetland through restoration of altered hydrology. In combination with forested wetlands, the refuge will provide a total of 1,920 acres of forested habitat, an important contribution in a state that has lost over half of its original forested habitat. Upland forest provides year round habitat for resident birds, mammals, reptiles, and amphibians. The refuge will manage upland forests with the overall goal to create mature upland forests that contain characteristics necessary for forest interior dwelling ROC. Specifically, mature upland forest provides habitat for the wood thrush, the eastern red bat, and other ROC that require a relatively closed canopy associated with large diameter trees in contiguous patches. The wood thrush is a forest interior bird, preferring patches at least 50 acres in size with 10 or more acres of forest interior (greater than 300 feet from nearest forest edge) dominated by trees 5 inches diameter at breast height or greater (Jones et al. 2001). Similarly, eastern red bats have been documented to roost in mature trees (more than 50 feet above ground) in the outer foliage of the canopy of 13 species of large hardwood trees, at least 150 feet from forest edges (Hutchinson and Lacki 2000). Mature trees also provide cavities, crevices, and sloughing bark that can be used by for roosting and foraging by numerous ROC. Some forest-dwelling species, such as the red bat, forage in forest openings and canopy gaps that form naturally over time in mature forest stands. Additionally, mature forest creates a higher potential for rare plant species, such as orchids, to develop. The refuge does not currently actively manage upland forests. Although a majority of the upland forest found on the refuge is early to mid-successional, the goals and strategies outlined in this HMP direct the refuge to allow for successional development of these areas to high quality mature forest, which is underrepresented in the Delmarva Peninsula. Additional active management will be considered to reduce invasive species pressure and the improvement of forest structure. Bombay Hook does provide public recreational opportunities for white-tailed deer hunting. The hunting program benefits habitat management objectives of the refuge, especially controlling the white-tailed deer population, which reduces herbivory. High white-tailed deer densities have been shown to alter the understory of forests and negatively affect neotropical migrant birds as well as small game populations (McShea and Rappole 2000, Rooney and Waller 2003). The refuge currently has reference sites of mature upland forest directly adjacent to early successional upland forest. The proximity of these areas allows for a side-by-side comparison of what is being passively managed (early successional forest) to what is preferred over time (mature forest). Because of the limited existing management in upland forest, results of active management (when employed) can be compared to existing forest stages present on the refuge to determine the effectiveness of management activities, further informing adaptive management. Information Needs The following management-related tools or additional data will help inform management decisions into the future: 1. Identification of forest reference sites to establish baseline conditions.

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2. Map invasive species distribution on the refuge to develop a priority list and strategy to control the future spread or elimination of specific invasive species.

3. Conduct a forest health inventory and assessment to understand species-specific detection and response needs which will determine specific techniques required to stop or mitigate spread of disease or insect infestations, if practicable.

4. Complete an updated inventory of vegetation composition and structure to inform the location, number and type of native tree plantings. Goal 2. Freshwater Wetlands Maintain the quality of the wetland habitats surrounding and within the refuge’s wetland impoundments, ponds, and moist soil units with seasonal management that benefit priority resources of concern. HMP Objective 2.1: Seasonally Managed Freshwater Impoundments Objective Seasonally manage the water depth and surface area of 685 acres of emergent marsh in managed freshwater impoundments to provide quality habitat for migrating and overwintering waterfowl (e.g., northern pintail), and other migrating and/or overwintering waterbirds (e.g., greater yellowlegs, semipalmated sandpiper). For Shearness, Raymond, Bear Swamp, and other managed impoundments attributes include: • Over fall and winter (October through March), the water depth across 50 to 75 percent of the impoundment surface area is 1-foot, and the remaining surface area (25 to 50 percent) is a mosaic of emergent vegetation (e.g., bulrush, smartweed, beggarticks, Panicum spp., Echinochloa spp.) as overwintering forage and cover for waterbirds (e.g. northern pintail, greater yellowlegs). • During spring migration (April through early June), water depths of less than 0.5-feet deep across 35 to 50 percent of the impoundment surface area, with the remaining surface area (65 to 50 percent) dominated by exposed mudflat with macroinvertebrates and native plants (e.g., bulrush, bur reed, smartweeds, sedges) as cover and forage for wading birds (e.g., greater yellowlegs). • Over summer (mid-June, after spring migration has passed, ending in September), receding waters slowly expose 35 percent of the impoundments’ moist soils to promote growth of at least two non-invasive native emergent grass or forb species (40 to 60 percent cover), create areas of pooled water that concentrate wading bird forage (e.g., mummichog, other fish), and maintain areas dominated by exposed sediments (less than 50 percent) to provide forage for other waterbirds (e.g., semipalmated sandpiper, greater yellowlegs). Management Strategies In order of priority using existing resources we may consider where applicable: 1. Continuing active water level manipulation as outlined in the HMP and prescribed in associated annual habitat work plans.

2. Annually treating populations of common reed with herbicide treatments, prescribed fire, and other tools that become available such as biological control.

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3. Annually conducting early detection and rapid response to prevent new populations of common reed, as well as newly introduced invasive species.

4. Over time, create about 20 acres of new small seasonally managed impoundments through contouring, creation of small berms, and/or installation or repair of water control structures. This new impoundment will be developed in hydric soils located on the Fischer tract primarily to provide enhanced habitat for wintering waterfowl habitat. However, the managed impoundment will also benefit other resources of concern (e.g., spotted turtles). With the contribution of additional resources (funding, staff, or partners) we will consider: 5. Implement sea level rise protection measures including, but not limited to dike stabilization, impoundment sediment deposition, or marsh restoration.

6. Maintain, replace, or remove aging infrastructure, as appropriate (i.e., water control structures, dikes, and other infrastructure that helps sustain management of impounded areas). Rationale Seasonally managed freshwater impoundments are human altered and managed wetland habitats where dikes and water-control structures have been constructed to restrict, retain, or exclude water over a selected area, and Delaware has a vast network of coastal impoundments along the Delaware Bay (DNREC 2015). Impoundment habitats vary depending on how the water depths and flows are controlled and, on the refuge, individual impoundments are annually managed to create mudflats, open water, and stands of emergent/submergent vegetation depending on the season and desired management goal (foraging, nesting, overwintering, etc.). The primary threat to this habitat is sea level rise (SLR). Current projections forecast that 81 percent of coastal impoundments will be inundated with a 0.5-meter rise of sea level and 99 percent will be inundated with a rise of sea level of 1.5 meters (DNREC 2015). The ability to effectively manage impoundment water levels is impacted by SLR through infiltration or a loss of management effectiveness, even if existing infrastructure is not completely overtopped and inundated. If sea level reaches an elevation that is above existing water control structures, but does not overtop levees and dams, the ability to drain the impoundments will be reduced. Additionally, at this elevation, saltwater could backflow through water control structures, altering the salinity of the freshwater impoundments and drastically changing vegetative and macroinvertebrate communities. The large coastal impoundments on the refuge (Shearness, Raymond, and Bear Swamp) were constructed between 1939 and 1961 and currently total approximately 665 acres, or approximately 4 percent, of the refuge. The total impoundment acreage (within levees) is larger than this estimate. Within each impoundment, some areas are represented by the semi-permanent freshwater marsh (described under the Semi-permanent Freshwater Wetland objective). Acreage for these areas are accounted for separately as they more representative of this habitat type, even though they are physically bounded by the impoundment infrastructure. Over time, the refuge plans to increase the total acreage of impoundments (not including semi-permanent freshwater marsh areas) to approximately 685 acres. This small increase of approximately 20 acres will be a result of creation or restoration of additional small impoundments. Seasonal impoundments are an essential part of Delaware’s habitat management efforts that help provide migratory habitat for many waterbirds, and potential overwintering habitat for reptiles (DNREC 2015). Waterbirds such as the greater yellowlegs and northern pintail are found on the refuge within the impoundments primarily during migration where open water is interspersed with emergent vegetation. The greater yellowlegs and northern pintail, as well as other ROC, use the impoundments during winter when open water and flooded annual vegetation remain to provide forage habitat and senesced vegetation is present to provide escape cover. Shorebirds, such as the semipalmated sandpiper, also use

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impoundment habitats primarily during migration, where sparsely vegetated or bare ground is present and provides forage habitat. See Chapter 3 for detailed habitat requirements for each priority ROC. Individual coastal impoundments are managed according to the seasonal management objectives at any given time of year, e.g. Shearness and Raymond may be simultaneously managed to provide different results (mudflat in one and open water in the other, etc.). Annual management cycles broadly prioritizes spring migration, which takes precedence to support forage at critical timing for shorebirds. Regardless of management intent or time of year, all three coastal impoundments are managed similar to moist soil units. Metrics provided in the objectives are optimal and not likely achieved in every unit in every season, especially considering that each unit has only natural (rainfall and groundwater) input and the topography/bathymetry between and within each unit varies greatly. However, the general guidelines for water level and vegetation management are outlined in the objectives and will further detailed in annual habitat work plans. While the ability to actively manage water levels in these human created habitats can help create and manage ideal habitat conditions for a wide variety of ROC throughout the entire year, the fact they are entirely anthropogenic in origin and function may eventually make their ongoing management prohibitive. Existing infrastructure, such as water control structures, dams, and dikes are susceptible to failure from aging and degradation. In addition, these water control structures are installed at a fixed elevation and as sea level continues to rise, the ability to draw down freshwater levels has become more challenging, because it must exit the impoundment into the adjacent tidal marsh through flap gates during low tide. Potential for damage from severe storm events (e.g. hurricanes, tropical storms, or super storms) could also cause catastrophic failure or breach of dikes. Evaluating these structures and assessing their utility and maintenance needs has been recommended (Wurster et al. 2013). We intend to manage these impoundments, and sustain the dynamic and critical habitat they contain, as long as feasible. However, we recognize that at some point in the next few decades, underlying conditions or catastrophic failure may make continued management or their repair prohibitive. If and when this becomes problematic, refuge staff will need to evaluate alternative management and adaptation strategies that allows for transition to other habitat types based on the conditions and future projections available at that time. Information Needs The following management-related tools or additional data will help inform management decisions into the future: 1. Continued improvement of hydrodynamic modeling in cooperation with academic and other partners.

2. Sea Level Rise modeling and improved assessment of threats to future management of water levels.

3. Conduct an infrastructure review, risk assessment, and return on investment strategy to determine if/when breaching or creating self-sustaining habitat may be more desirable.

4. Conduct or review a water quality assessment to assess eutrophication and groundwater trends to inform management decision regarding impoundment water level management. HMP Objective 2.2: Semi-permanent Freshwater Wetlands Objective

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Protect 280 acres of freshwater, non-tidal, emergent wetlands to provide resting and foraging habitat for migrating and nesting waterfowl and other waterbirds (e.g. least bittern), as well as resident herpetiles (e.g. spotted turtle, wood frog), with the following attributes: For Finis Pool: • Annually sustain water depths that maintain a mix of at least 20 percent freshwater emergent vegetation and up to 80 percent shrub scrub. Shrub scrub is dominated (greater than 50 percent cover) by native species including buttonbush, beggarticks, pickerelweed, and yellow waterlily. For All Other Semi-permanent Freshwater Wetlands (including portions of other impoundments): • At least 50 percent cover of native emergent vegetation such as bulrush, cattail, and sedges.

• Invasive species, including common reed, are contained at less than 10 percent cover across each wetland. Management Strategies In order of priority using existing resources we may consider where applicable: 1. Continuing to passively maintain water levels favoring native emergent vegetation and open water. In Finis Pool, limited water level manipulation is conducted, such as to facilitate water level increases in adjacent Shearness Pool or protect the dike road from overtopping. 2. Annually treating populations of common reed with herbicide treatments, prescribed fire, and other tools that become available such as biological control. 3. Annually conduct early detection and rapid response to prevent new populations of common reed as well as newly introduced invasive species. 4. Periodically reintroduce native species such as bulrush and sedges as necessary to recolonize areas formerly dominated by common reed, or to supplement native species where needed. With the contribution of additional resources (funding, staff, or partners) we will: 5. Conduct additional invasive species control treatments to reduce monocultures of common reed and cattail. Rationale Wetlands (tidal and nontidal, freshwater and brackish) are Delaware’s most significant natural feature, covering 25 percent of the State. Although more than 70 percent of all wetlands in the State are non-tidal freshwater wetlands (of which this habitat type is considered), Delaware is one of 16 states that has experienced more than 50 percent wetland loss. The majority of this loss in the State was to freshwater wetlands due to ditching, channelization, conversion to open water, and development. Many remaining wetlands are degraded due to sedimentation, nutrient enrichment, and invasive plant infestations (DNREC 2015). While regulations limit additional permanent losses to federally jurisdictional wetlands (Waters of the U.S.), there are limited protections for isolated wetlands on the State level, further justifying the need for perpetual protection of this critical habitat on the refuge. Additionally, SLR of 1.0 meter is expected to inundate 33 percent of Delaware’s remaining non-tidal emergent wetlands and 22 percent of non-tidal shrub wetlands, altering salinity (DNREC 2015). Similarly, as summer temperatures are projected to increase as a result of climate change, the duration of seasonal inundation and stable water levels could be lessened, resulting in the drying of soils and a shift of wetland to mesic or upland plant communities, such as the invasive common reed.

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Most of the refuge’s semi-permanent freshwater wetlands are man-made and consist of flooded gravel pits, formerly ditched areas, and depressional areas impounded by dikes or roads (Wurster et al. 2013). Due to this habitat being mainly defined by its vegetation composition and landscape setting, it is closely aligned and interspersed with other habitats. Two sub-component communities are represented by this broad habitat type, emergent freshwater marsh and freshwater shrub swamp. The emergent freshwater marsh community can be found both within and outside of the seasonally managed freshwater impoundments and is represented by persistent emergent vegetation such as sedges, bulrushes, cattail, and common reed. Outside of the impoundments, these herbaceous wetlands typically occur in basins or ditches which are generally flat and shallow that are permanently or semi-permanently flooded. The freshwater shrub swamp communities is primarily found within the Finnis impoundment and is represented by buttonbush, beggarticks, pickerelweed, and yellow waterlily. Freshwater wetlands are considered in Delaware as being of high importance for biodiversity considering all of the species of greatest conservation need that utilize the habitat (DNREC 2015). Freshwater wetlands consisting of shallow water interspersed with emergent cover and high invertebrate abundance are important for migrating and resident waterfowl, landbirds, and waterbirds. Represented by the least bittern, which requires tall, dense vegetation over stable water levels, refuge emergent marshes provide breeding, foraging, and escape cover for a suite of ROC. A variety of reptiles and amphibians also utilize the refuge freshwater wetlands and rely on the stable water levels and soft substrates they provide for breeding, foraging, and overwintering habitat as represented by the spotted turtle. This species requires shallow water over soft substrate (especially for overwintering hibernacula) within close proximity to other natural areas such as forested wetlands containing vernal pools and secluded uplands with dense vegetation. The rationale for Objective 3: Seasonally Managed Freshwater Impoundments contains additional information regarding additional ROC that occupy these habitats. Chapter 3 also details specific habitat requirements associated with each priority ROC. These wetland habitats coincide with the migratory, nesting, foraging, and overwintering habitat for many of the same species listed in that objective. The refuge contains currently contains approximately 300 acres of semi-permanent freshwater wetlands (both inside and outside the impoundments), which represents approximately 1.9 percent of the total refuge area. Over time, the refuge plans to decrease this total to approximately 280 acres, approximately 1.7 percent of the total land cover. This will be a negligible decrease of approximately 20 acres, which is planned for conversion of common reed dominated emergent freshwater marsh to forested wetland as vegetation around these wetlands are allowed to continue their trajectory towards mature forest. As they do, the mature trees will eventually shade and surround these small wetland areas. Finis Pools is constrained in its potential for water management due to a combination of factors. First, Finis Pool is the only major impoundment with a regular supply of fresh water from Finis Branch. Next, freshwater from Finis Pool enters Shearness Pool through two structures built into Finis Dike, so waters in Finis are managed with consideration for Shearness Pool. Last, to prevent overtopping or saturation of Finis Dike, water levels in Finis Pool are always maintained 3 feet or more below the elevation of the dike road. Because of these constraints, Finis Pool is maintained at a relatively stable water elevation, which sustains the semi-permanent wetlands (Wurster et al 2013; Bombay Hook NWR staff pers. comm. 2018). Outside of Finis pool, which is only drained as infrastructure (dike) protection, semi-permanent freshwater wetlands do not receive water level manipulation, and therefore, require less management than habitats like seasonally managed freshwater impoundments. Our strategies support habitat conservation needs through the maintenance of invasive species encroachment, specifically common reed and cattail, to conserve native plant diversity and ecosystem function. Restoration of wetlands by eradicating existing monocultures of common reed and cattail and subsequent seeding with native species could be immediately assessed for efficacy of the restoration and enhancement of BIDEH by direct observations of priority and non-priority ROC.

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Information Needs The following management-related tools or additional data will help inform management decisions into the future: 1. Inventory and map extent of invasive species (primarily common reed and cattail) to better understand the extent of invasive species cover in habitat.

2. Efficacy of various methods from the region (especially other refuges) for removal of monocultures and replacement with native species.

3. Expand marsh bird surveys to assess contribution of isolated freshwater wetlands to ROC.

4. Conduct surveys to assess the extent of herptile use (especially spotted turtles) in freshwater wetlands.

5. Conduct or review a water quality assessment to assess eutrophication and groundwater trends. Goal 3. Coastal Salt Marsh Habitats Perpetuate and restore the biological integrity, diversity, and environmental health of tidal salt marsh and associated tidal shrub and beach habitats to benefit priority resources of concern. Diminish marsh loss and ensure natural sustainability. HMP Objective 3.1: Tidal Salt Marsh Objective Manage approximately 12,800 acres of tidal salt marsh to maintain salt marsh habitat integrity for the benefit of wetland species (e.g., saltmarsh sparrow, clapper rail, and American black duck). We will manage salt marsh habitat for the following attributes: • A mosaic of native salt marsh vegetation consisting of infrequently flooded high marsh dominated by salt meadow cordgrass and salt grass, frequently flooded low salt marsh vegetation dominated by smooth cordgrass, along with pool, panne, and mudflat habitat.

• Less than 15 percent overall cover of invasive plants as consistent with local reference sites (infestation of common reed contained to baseline 2018 levels).

• No more than 20 to 25 percent cover of unvegetated marsh (e.g., pools, pannes, and mudflat)

• Areas of high marsh dominated (greater than 50 percent cover) by native shrubs between 5 and 15 feet tall (e.g., groundsel bush and high tide bush). • Breeding tidal marsh obligate bird species (saltmarsh sparrow, seaside sparrow, clapper rail) with mean abundances consistent with current (2011 to 2018 average) population levels

• Marsh platform elevation change that keeps pace with the local rate of relative sea level rise (3.48 mm/yr; Lewes, DE station) Management Strategies In order of priority using existing resources we may consider where applicable:

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1. Reducing existing common reed infestations and using early detection rapid response to prevent expanded or new infestations.

2. Continuing passive management (regularly monitoring for integrity of habitat). 3. Identifying, evaluating, prioritizing, and beginning to implement other SLR protection measures, such as looking for opportunities to manage tidal marsh transgression on refuge-managed lands and developing and implementing other active restoration projects as appropriate. With the contribution of additional resources (funding, staff, or partners) we will consider: 4. Implementing thin layer deposition projects to offset sea level rise impacts.

5. Restoring historic hydrology to areas of human-caused disturbance (mosquito ditching).

6. Identifying, evaluating, prioritizing, and beginning to implement longer-term restoration measures, such as considering changes to impoundment management as described above. Rationale Salt marsh is one of the most extensive habitats along the Atlantic coast, is the predominant estuarine habitat in Delaware and is considered to be one of the most important wildlife habitats in North America. The State of Delaware is responsible for up to 9 percent of the modeled salt marsh in the Northeast, but has only 1 percent of the total land area (DNREC 2015). The Delaware Bay Estuary Wetlands System, including the salt marshes of the refuge, was recognized as a Ramsar wetland of international importance in 1992. This designation was based on its contribution as an important staging habitat for over 90 percent of the North American populations of several migratory shorebird species. Tidal salt marsh type consists of several different and distinct plant communities that develop according to elevation and corresponding level of salinity. The typical salt marsh profile, from heaviest to lightest salinity, features a low-lying, regularly flooded low marsh that is dominated by smooth cordgrass, then an irregularly flooded high marsh of salt meadow cordgrass. In open exposed areas, salt panes form in depressions where salt accumulates and are characterized by glassworts. Last, and at the highest elevations relative to high tide, a salt scrub-shrub margin is often found between the marsh edge and upland with southern marsh elder and groundselbush (DNREC 2015). As with impounded wetlands, sea level rise poses the primary threat to salt marsh habitat. Increasing sea levels are expected to cause shifting of plant communities, invasive species introductions, fragmentation, degradation, or outright loss of the habitat. Increases in sea levels threaten marshes by either converting areas of low marsh by causing a shift to open water, or submerging high marsh, resulting in a conversion to low marsh. After sea level rise, invasive species within salt marsh habitats pose the next highest threat to ecological integrity. Common reed poses the primary invasive species threat to salt marshes. This species threatens many of the high marsh components of the broad habitat, but can expand into lower marsh areas once established (DNREC 2015). Salt marsh habitat sustains a variety of wildlife including migrating waterfowl, waterbirds, landbirds, and shorebirds that follow the network of marshes up and down the coast twice each year in spring and fall. These habitats also support breeding for a number of migratory birds that require the dense vegetation, available forage, and protected isolation provided by salt marsh habitat. The mix of dense vegetation and open water support landbird nesting and migratory stopover habitat, as represented by the saltmarsh sparrow. Saltmarsh sparrow and other migratory birds nest in high marsh areas, as well as altered, tidally restricted marsh in open stands of short common reed where salt meadow cordgrass is the prevalent ground cover (DiQuinzio et al. 2002). Waterfowl, represented by American black duck, rely on these marshes for breeding and overwintering habitat. Salt marsh and tidal habitats are essential habitats for American black duck and waterfowl, especially at night and when ice forms (Conroy et al. 1987, Morton

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et al. 1989). Similarly, wading birds and shorebirds rely on this habitat for migratory stopover and nesting habitat, as evidenced by clapper rail and other similar species. The refuge currently contains approximately 12,800 acres of salt marsh, which represents approximately 79.6 percent of the total refuge area. Although no specific changes are proposed by active management of refuge salt marsh at this time, natural fluctuations of this estimated acreage are expected. Natural processes largely sustain, and change, the salt marshes through exposure to ongoing tidal fluctuation, natural marsh accretion and erosion, and other geomorphic processes. Although radiometric isotope analysis suggests that vertical accretion in the refuge’s tidal marshes is keeping pace with current rates of sea level rise, there has been significant marsh loss in recent decades (McDowell 2017). Trends of concern in refuge tidal marshes include a loss of approximately 2000 acres (860 ha) of marsh since 1961. About half of that loss is due to formation or expansion of pools in the marsh interior. About a third of the loss is due to shoreline erosion on the bayshore and the remaining loss is due to channel widening (McDowell 2017). Hydrodynamic modeling indicates that the refuge marshes are ebb-dominated now experiencing a net export of sediment from the wetland system, likely due to past alterations (Deb et al. 2018). Ongoing shoreline erosion makes the entire system vulnerable to potential changes in hydrology in the future. Research, monitoring, and modeling of the hydrological patterns that may be influencing these losses is ongoing. Habitat management strategies for salt marshes are focused on protecting existing conditions, reducing invasive species cover, and monitoring for potential effects of sea level rise. As a result of the vulnerability and uncertainty posed by sea level rise, establishing long-term and consistent monitoring of the habitat is considered a necessity to observe the subtle changes and trends that may occur. The knowledge gained through this ongoing monitoring will inform the adaptation and management strategies required for future habitat management. These additional restoration and management strategies could include proactive restoration of marsh elevation, facilitation of landward tidal marsh transgression, hydrological alterations, or the installation of living shorelines in areas of erosion, if monitoring information and research support their consideration. The region’s salt marsh integrity (SMI) program is in place to improve monitoring of salt marsh habitats on refuges in order to better inform management decisions. The SMI protocol identifies indicators of salt marsh integrity that are effective across large geographic areas, responsive to a wide range of threats, and feasible to implement within logistical constraints, namely funding and staffing (Neckles et al. 2013). Surveys consist of evaluation of breeding marsh bird, nekton, vegetation, water levels, and salinity. These considerations are weighed together into a cumulative integrity score for the marsh areas assessed. The refuge has a set of baseline SMI data and scores for all refuge salt marsh units following an initial round of implementing the protocols between 2012 and 2014. A structured decision-making process was utilized to build on the SMI baseline data and develop and evaluate a reasonable range of management and restoration actions and optimization alternatives for refuge salt marshes, which serve as a starting point for future management (Neckles et al. 2018). However, because the SMI program and protocols are undergoing revisions, the SMI score will not be used directly for monitoring at this time. The refuge will remain engaged in the SMI program to improve collection of information about long-term trends in the health of salt marsh habitat on the refuge. Despite the extensive area of salt marsh along the Delaware coast, there is still much to be understood about this habitat. The habitat objective relies on salt marsh integrity information, which has been gathered from refuges located throughout the USFWS’ Northeast Region. Ongoing collection and refinement of targets resulting from this data will help inform future management of salt marshes and improve our understanding of its ecological integrity and management response. Similarly, ongoing refinement of sea level rise modeling will continue to inform future management and marsh resiliency or adaptation strategies. This information can also be coupled with hydrological modeling research conducted by state and academic partners in the refuge’s tidal marsh system.

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Information Needs Management is driven, in part, by uncertainty (overall marsh trends, high/low marsh composition and trends). Areas we need to better understand to inform management direction: 1. Updated or refined SLR modeling/assessments (conversion of high salt marsh to low salt marsh, etc.).

2. Modeling of hydrodynamics across the marsh during tidal fluctuation and scenario modeling for consideration of future erosion or changes or to evaluate restoration or management alternatives.

3. How do we best measure and track high marsh component, solid vs “rotten” high marsh specifically? Composition is similar, but “rotten” marsh is more hummocky, less stable, and more easily lost in storm events (Potential for Synthetic Aperture Radar).

4. Potential threats from oil spills in Delaware Bay and current status of spill response planning in the Delaware Bay.

5. Regularly updated extent/mapping of common reed. 6. Effects of herbivory (snow goose and muskrat “eat outs”). Flats are colonized by smooth cordgrass, but then lost to herbivory or ice. Need to understand limiting factors to inform future enhancement or restoration strategies. HMP Objective 3.2: Beach Objective Protect approximately 30 acres of naturally functioning sandy beach and dune habitat, the narrow band between the highest normal tide and edge of low tide, to provide resting and foraging areas for migrating shorebirds (e.g., sanderling) with the following attributes: • Sparsely (less than 25 percent cover) vegetated open sand and gravel, or shell-covered substrate, • Dune vegetation dominated by sea rocket, purple sandgrass, seaside spurge, and goldenrod, and • No presence of invasive species, such as common reed. Management Strategies In order of priority using existing resources we may consider where applicable: 1. Continuing to sustain beach habitat through passive management resulting from salt spray, storm surge, and tidal fluctuations along the Delaware Bay. Rationale Beach habitat on the refuge represents a narrow and transient band of relatively open sandy and gravel habitat located between the normal high tide and the edge of the low tide. This habitat makes up approximately 30 acres, or less than 1 percent, of the refuge. With a rich diversity of invertebrates and sparse vegetation consisting primarily of sea rocket (Cakile spp.), purple sandgrass (Triplasis purpurea), seaside spurge (Chamaesyce polygonifolia), goldenrod (Solidago spp.), it provides resting, foraging, migrating, and staging areas for shorebirds. Based on its location, it may also act as a buffer against erosion and wave action that threatens to impact salt marsh habitats. Threats to beach habitat on the refuge include SLR, oil spills and other pollution, and invasive species establishment. Beach habitat is low priority for refuge management because there is a minimal amount of

4.0 Habitat Goal, Objectives, and Management Strategies 4-24 August 2020 Habitat Management Plan for Bombay Hook National Wildlife Refuge it within the refuge and the process that maintains it, frequent natural disturbance, does not require additional manipulation. Additionally, the location of beach habitat within the refuge is difficult to access and relies on timing related to tides and weather conditions. Information Needs The following management-related tools or additional data will help inform management decisions into the future: 1. Assess the trends, and extent, of beach across the refuge.

2. Invertebrate diversity and density. Goal 4. Early Successional Upland Habitats Maintain, enhance, and/or restore the vegetation, biological integrity, diversity, and environmental health of early successional habitats that benefit priority resources of concern. HMP Objective 4.1: Early Successional Uplands Objectives Manage approximately 370 acres of early successional upland and associated seasonally wet habitat to support migrating and resident landbirds (e.g., brown thrasher and northern bobwhite quail), with a mosaic of grasses, forbs, and shrubs that include larval insect host plants and nectar-producing forbs for pollinators (e.g., monarch butterfly) and also benefitting other species such as migrating waterfowl (e.g., northern pintail and American black duck). We will manage grasslands and old fields for the following attributes: • Up to 60 percent cover of native grasses (such as little bluestem, Indian grass, switch grass, and big bluestem) and non-native grasses (such as red fescue and orchard grass) with no single species exceeding 20 percent of the total grass cover. • Nectar-producing plants (e.g., violets, milkweeds, asters, and goldenrods) that bloom from May through October with a minimum of 30 percent cover comprised of native forbs. • Native shrubs and trees (such as groundsel bush, black cherry, oaks, tulip poplar, and blackberry) with heights between 1 and 5 feet covering no more than 35 percent of the habitat. • Minimal or zero percent cover of State-defined noxious weed species, and no more than 20 percent of other ecologically invasive species. Management Strategies In order of priority using existing resources we may consider where applicable: 1. At least once every 3 years, maintaining the open, early successional, herbaceous dominated structure through a combination of mowing and/or burning across up to 1/3 of all grassland units. 2. Annually conducting invasive species treatments for priority populations of invasive species including Canada thistle, mile-a-minute vine, multiflora rose, and autumn olive. 3. Planting or seeding native species, especially native flowering nectar plants, to increase species diversity and extend nectar availability throughout the growing season. 4. Install cereal small grains (non-GMO) and/or annual forage species (clover) on up to 80 acres of current non-native cool season grassland. Half of the initial 80 acres of planted small grain acreage will be left fallow each year resulting in 40 acres of planted acreage and 40 acres of fallow acreage.

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With the contribution of additional resources (funding, staff, or partners) we will consider:

5. Managing shrubland where appropriate to set back succession to maintain grassland habitat. Rationale Early successional uplands in Delaware are associated with abandoned agricultural areas or areas exposed to historic and/or ongoing disturbance. Vegetation communities typically include a mosaic of herbaceous dominated habitats such as agricultural pasture, grasslands, managed and unmanaged grass- and forb- dominated habitats as well as shrub dominated habitats. The two main community types present on the refuge that represent this broad habitat type are early successional herbaceous and early successional shrubland (as defined by DNREC 2015). Currently, timber harvest lands and periodically managed rights- of-way are the dominant examples of early successional uplands elsewhere in the state. Historic disturbance regimes (fire, storms, etc.) did not create or maintain these habitat types in vast quantities historically and they are no longer functional in a fragmented landscape (DNREC 2015); therefore, refuge management is intended to mimic these natural disturbances to create and/or sustain these habitats. Early successional uplands adjacent to the Delaware Bay are considered important regional habitat during migration for the monarch butterfly, which is currently under review for protection under the ESA, as the species may seek refuge for several days in these areas, awaiting suitable conditions before crossing the bay. Other priority ROC for this habitat, the northern bobwhite quail and the brown thrasher, have experienced populations declines of 6 percent (Brennan et al. 2014) and 2.2 percent (Cavitt et al. 2014) per year in the Northeast, respectively, both likely as a result of habitat loss. Early successional habitats are important not only to the priority ROC that require them for breeding, foraging, and overwintering, but also for forest interior species, which rely on early successional uplands during post-breeding and fall migration (DNREC 2015). Similarly, a variety of landbirds, mammals, reptiles, and amphibians use early successional uplands during all life stages or as habitat corridors between their preferred habitats. Waterfowl of all species have been observed using temporary sheetwater wetlands that form for short periods of time in early sucessional habitats, especially during spring migration. Grassland dependent species of the refuge are represented by the monarch butterfly which requires open fields and meadows with milkweeds, nectaring forage plants, and are vulnerable to pesticides (Center for Biological Diversity et al. 2014). Improving the habitat for grassland dependent species is especially important for pollinators, including the population viability of the monarch butterfly. Incorporating seed mixes that include species such as little bluestem, Indian grass, switch grass, big bluestem, red fescue, orchard grass, violets, milkweeds, asters, and goldenrods will significantly add to the overall habitat suitability or grasslands. It is observed that species richness is positively correlated to pollinator utilization more so than age or size of the grassland or total number of flowers. This suggests that installing varied seed mixes containing multiple forb species with varying bloom timeframes is the most important consideration when managing grassland habitats for pollinator species (Reed 1993). Shrubland dependent species are represented by the brown thrasher which requires thickets and scrubby fields for nesting and are sensitive to habitat fragmentation and canopy tree species encroachment. Improving habitat quality for shrub dependent species is vital to the long-term success of the brown thrasher. Creating and maintaining dense thickets or linear shrubby “fencerows,” especially with fruit bearing woody species in contiguous patches adjacent to open grasslands, it may slow their decline as food supply is believed to be a limiting factor for population viability. Overall, early successional uplands (consisting of mosaics of grasslands and shrublands) are represented by the northern bobwhite quail, which requires open grasslands for nesting interspersed with shrubs for escape cover and foraging. Shrub cover is especially important to provide forage sources (either from fruit or insects) and to maintain areas of ground with leaf litter and limited snow cover during winter months to provide ground forage opportunities. By managing early successional upland habitat as a mosaic of both grasslands and shrublands, habitat requirements for the northern bobwhite quail are expected to be met.

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Grasslands and shrublands both require constant disturbance to maintain them in their successional stage. Natural disturbances such as fire and windthrow are severely limited by today’s landscape fragmented by development and agricultural lands. To mimic these natural disturbances, grasslands will be actively managed through mowing, burning, herbicide application, and other tools. Despite management, some shrub encroachment is expected as a result of our limited management resources. As grasslands become more shrub dominated, we will consider where and when to reset succession with intensive active management. By selecting priority ROC that have a wide range of tolerance of woody species encroachment, we will be able to manage all grasslands and shrublands as a constantly shifting (both spatial and successional) mosaic of early successional uplands benefitting all species simultaneously. Each community type will be managed independently, but planning associated with annual work and results of surveys planned in the IMP will guide adaptive management strategies to best benefit the priority ROC as these changes occur. Early successional upland habitats, as a result of disturbance, are also areas of high potential for invasive species introductions. To combat the potential for invasive species encroachment, we will continuously manage the control of invasive species where it occurs on the refuge, and especially where it threatens to spread into these managed habitats. Autumn olive, a shrub species, and Canada thistle, an herbaceous species, are aggressive but common examples of invasive species that thrive is disturbed areas. Controlling invasive species will require a triage approach, concentrating on preventing initial establishment first using early detection rapid response, then focusing on containing and eventually reducing monocultures. Where possible, we will incorporate management that both maintains successional stage and simultaneously control invasive species. Currently, approximately 3.7 percent, or 595 acres, of the refuge is composed of early successional uplands. Over time, the refuge plans to decrease this total to approximately 370 acres, approximately 2.3 percent of the total land cover. This will be a gradual decrease of approximately 225 acres as habitat restoration transitions some areas from early successional upland to either upland forest or forested wetland. Because early successional uplands are expected to perpetually contain invasive species, some fields will be regularly planted with annual species, primarily in areas associated with consumptive use. We intend to manage for this habitat along the outer periphery of refuge, locating these constantly disturbed sites away from core habitats. Other areas of the refuge where management of this habitat will be focused include the smaller fields and tracts around the headquarters area and the large impoundment complex. Acreages of grasses, forbs and woody species will not be static; this habitat is very dynamic. A mosaic of these three vegetation types will fluctuate as natural succession progresses, and is set back occasionally with implementation of our management efforts. In conjunction with annual vegetative maintenance to maintain and/or set back succession and native species seeding to increase diversity, the refuge proposes to install annual cereal grains and/or annual forage species such as clover annually on up to 80 acres of what is currently non-native cool season grasslands that developed on former agricultural lands. The planted small grain/forage crop acreage will not be harvested and allowed to go fallow each summer, allowing forbs to grow. High yield annual grains in association with native forbs/grasses in the adjacent fallow areas will be used to supplement foraging needs for migratory waterfowl, the northern bobwhite quail, and to compensate for grassland habitat losses to shrubland succession or forest restoration. A combination of annual small grains with fallow fields can provide winter cover and spring “bugging” areas and brood-rearing habitat for gallinaceous birds such as northern bobwhite quail (Pierce et al. 2008). Currently, there is limited spatial availability for grassland forage elsewhere on the refuge, and this existing acreage will decrease over time with restoration to alternate habitat types. The refuge hopes to offset these spatial losses by increasing the density of available grain forage in remaining areas. Additionally, these annual plantings will benefit species typically associated with hunting (migrating waterfowl, white-tailed deer, turkeys etc.) and by concentrating this seeding in grasslands on the periphery of the refuge, consumptive use will be more focused in those areas and less focused in the center of the refuge where other recreation takes place.

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Information Needs The following management-related tools or additional data will help inform management decisions into the future: 1. Thresholds/metrics for conflicting habitat management guidance based on updated local, regional, and national studies. Answer questions such as, “Is up to 35 percent shrub cover an appropriate target for composition across the refuge’s early successional uplands to address conservation needs of ROC species?”

2. Better understanding of secondary benefits to other ROC tied to other habitat types (such as forested interior birds post-breeding use; American woodcock singing grounds; insect diversity and density surveys in shrub dominated areas versus grass dominated areas versus forest edges to better understand foraging use, etc.).

INVENTORY AND MONITORING PLANNING Concurrent with or immediately following the preparation of this HMP, we will develop an IMP per the Inventory and Monitoring (I&M) policy (701 FW 2) to establish strategies needed to measure achievement of stated objectives. Additionally, annual habitat work plans (AHWPs) will be produced to respond to immediate, site-specific needs in individual habitats, which may require the adjustment of previously determined management priorities (see Figure 1-2). In developing, reviewing, and revising these management planning efforts and executing associated management and monitoring actions, refuge complex staff will implement an adaptive management framework to inform future management.

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CHAPTER 5. MANAGEMENT UNIT DESCRIPTIONS The refuge has been divided into seven management units (HMUs) based on a combination of habitat- based and geographical boundaries (Figures 5-1 through 5-8). Chapter 5 (Management Units) will contain more site-specific planning that will provide refuge staff with details on how to implement the goals, objectives, and strategies outlined in the HMP. Because the management unit-specific details of implementation support internal refuge implementation of this plan, Chapter 5 will be developed further following agency and public review of the HMP.

5.0 Habitat Management Units 5-1 August 2020 Habitat Management Plan for Bombay Hook National Wildlife Refuge

Figure 5-1. Habitat Management Units (HMU) at Bombay Hook NWR.

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Figure 5-2. Fisher Tract HMU at Bombay Hook NWR

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Figure 5-3. Dutch Neck HMU at Bombay Hook NWR

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Figure 5-4. Headquarters Area Managed Impoundments HMU at Bombay Hook NWR

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Figure 5-5. Headquarters Area Early Successional HMU at Bombay Hook NWR

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Figure 5-6. Air Force Tract HMU at Bombay Hook NWR

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Figure 5-7. Steamboat Landing HMU at Bombay Hook NWR

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Figure 5-8. Salt Marsh HMU at Bombay Hook NWR

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CHAPTER 6. REFERENCES CITED Adamcik, R.S., E.S. Bellatoni, D.C. DeLong Jr, J.H. Schomaker, D.B. Hamilton, M.K. Laubhan, and R.L. Schroeder. 2004. Writing Refuge Management Goals and Objectives: A Handbook. Department of the Interior, U.S. Fish and Wildlife Service, Washington, DC. Accessed August 2018 at: https://www.fws.gov/refuges/policiesandbudget/pdfs/WritingRefugeGoals_022504.pdf. Allen, M.C., M.M. Napoli, J. Sheehan, T.L. Master, P. Pyle, D.R. Whitehead, and T. Taylor (2017). Acadian Flycatcher (Empidonax virescens), version 2.0. In The Birds of North America (P.G. Rodewald, Editor). Cornell Lab of Ornithology, Ithaca, NY, USA. https://doi.org/10.2173/bna.acafly.02 Atlantic Coast Joint Venture Management Board. 2005. North American Waterfowl Management Plan, Waterfowl Implementation Plan, Revision 1. Black Duck Joint Venture Management Board. 2008. Black Duck Joint Venture Strategic Plan, 2008– 2013. U.S. Fish and Wildlife Service, Laurel, MD; Canadian Wildlife Service, Ottawa, Ontario. 27 March. Brennan, L.A., F. Hernandez, and D. Williford (2014). Northern Bobwhite (Colinus virginianus), version 2.0. In The Birds of North America (A.F. Poole, Editor). Cornell Lab of Ornithology, Ithaca, NY, USA. https://doi.org/10.2173/bna.397. Brown, S., C. Hickey, B. Harrington, and R. Gill, eds. 2001. The U.S. Shorebird Conservation Plan, 2nd ed. Manomet Center for Conservation Sciences, Manomet, MA. Buler, J and D. Dawson. 2014. Radar analysis of fall bird migration stopover sites in the northeastern U.S. Ornithological Applications 116: 357-370. Caro, T. 2010. Conservation by Proxy: Indicator, Umbrella, Keystone, Flagship and Other Surrogate Species. Island Press, Washington, DC. 374 pp. Cavitt, J.F. and C.A. Haas (2014). Brown Thrasher (Toxostoma rufum), version 2.0. In The Birds of North America (A.F. Poole, Editor). Cornell Lab of Ornithology, Ithaca, NY, USA. https://doi.org/10.2173/bna.557. Clark, K.E. and L.J. Niles. 2013. U.S. Shorebird Conservation Plan: Northern Atlantic Regional Shorebird Plan, Version 1.0. Clark, R.G., J.P. Fleskes, K.L. Guyn, D.A. Haukos, J.E. Austin, and M.R. Miller (2014). Northern Pintail (Anas acuta), version 2.0. In The Birds of North America (A.F. Poole, Editor). Cornell Lab of Ornithology, Ithaca, NY, USA. https://doi.org/10.2173/bna.163. Coxe, R.B. 2008. Bombay Hook National Wildlife Refuge – Final Report on Vegetation Community Surveys: 2007-2008. Delaware Department of Natural Resources and Environmental Control. Submitted to Bombay Hook National Wildlife Refuge December 2008. 69 pp. Daly P. 1992. Bombay Hook National Wildlife Refuge Hunt Management Plan. Deb, M., Abdolali, A., Kirby, J. T. and Shi, F. 2018. Hydrodynamics, sediment transport and wind waves in an eroding salt marsh environment. Bombay Hook National Wildlife Refuge, Delaware, Research Report No. CACR-18-04, Center for Applied Coastal Research, Department of Civil and Environmental Engineering, University of Delaware.

6.0 References Cited 6-1 August 2020 Habitat Management Plan for Bombay Hook National Wildlife Refuge

Delaware Division of Natural Resources and Environmental Control (DNREC), Division of Fish and Wildlife (DFW). 2015. The Delaware Wildlife Action Plan, 2015-2025. Accessed on 21 Aug 2018 at: http://www.dnrec.delaware.gov/fw/dwap/Pages/WAP-Progress.aspx Delaware Office of State Planning Coordination. 2015. Delaware Strategies for State Policies and Spending. Elphick, C.S. and T.L. Tibbitts (1998). Greater Yellowlegs (Tringa melanoleuca), version 2.0. In The Birds of North America (A.F. Poole and F. B. Gill, Editors). Cornell Lab of Ornithology, Ithaca, NY, USA. https://doi.org/10.2173/bna.355. Engelhart, S.E, and Horton, B.P. 2012. Holocene sea level database for the Atlantic coast of the United States. Quaternary Science Reviews (54), pp 12-25. Evans, M., E. Gow, R.R. Roth, M.S. Johnson, and T.J. Underwood (2011). Wood Thrush (Hylocichla mustelina), version 2.0. In The Birds of North America (A.F. Poole, Editor). Cornell Lab of Ornithology, Ithaca, NY, USA. https://doi.org/10.2173/bna.246. Greenlaw, J.S., C.S. Elphick, W. Post, and J.D. Rising (2018). Saltmarsh Sparrow (Ammospiza caudacuta), version 2.1. In The Birds of North America (P.G. Rodewald, Editor). Cornell Lab of Ornithology, Ithaca, NY, USA. https://doi.org/10.2173/bna.sstspa.02.1. Hess, G.K., R.L. West, M.V. Barnhill III, L.M. Fleming. 2000. Birds of Delaware. University of Pittsburgh Press. 635 pp. Hicklin, P. and C.L. Gratto-Trevor (2010). Semipalmated Sandpiper (Calidris pusilla), version 2.0. In The Birds of North America (A.F. Poole, Editor). Cornell Lab of Ornithology, Ithaca, NY, USA. https://doi.org/10.2173/bna.6. Holdahl, S.R. and Mossison, N.L. 1975. Regional Investigations of Vertical Crustal Movements in the U.S., Using Precise Relevelings and MareoGraph Data. Tectonophysics, V.23, pp. 373-390. Holgersen, N.E. 1995. Wildflowers of Bombay Hook National Wildlife Refuge – A Preliminary List. 10 pp. Holgersen, N.E. and B. McAvoy. 1999. Trees, Shrubs and Ferns of Bombay Hook National Wildlife Refuge – A Preliminary List. 4 pp. International Union for Conservation of Nature (ICUN). 2016. Threats Classification Scheme (Version 3.2) and Red List Johnson-Pohlman, M. and J.D. Hewes. 1995. Fish of Bombay Hook National Wildlife Refuge, Smyrna, DE. 4 pp. Jones, C., J. McCann, S. McConville (2001). A Guide to the Conservation of Forest Interior Dwelling Birds in the Chesapeake Bay Critical Area. Critical Area Commission for the Chesapeake and Atlantic Coastal Bays, Annapolis, MD, USA. 58 pp. Kelley, J., S. Williamson, T.R. Cooper. 2008. American Woodcock Conservation Plan: A Summary of and Recommendations for Woodcock Conservation in North America. February. Kraft, J.C., 1976. Radiocarbon dates in the Delaware coastal zone (Eastern Atlantic Coast of North America): a Delaware Sea Grant Technical Report (DEL-SG-19_76), published by Coll. of Marine Studies, University of Delaware, Newark, 12pp. Neckles, H.A., Lyons, J.E., Nagel, J.L., Adamowicz, S.C., Mikula, T., Guiteras, S.T., and Mitchell, L.R. 2018. Optimization of salt marsh management at the Bombay Hook National Wildlife Refuge,

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Delaware, through use of structured decision-making (ver. 1.1, May 2019): U.S. Geological Survey Open-File Report 2018–1160, 29 pp. Accessed August 2019 at https://doi.org/10.3133/ofr20181160. Knutson, M.G., Tonneson, H.A., Wood, D., O’Brien, K., Wirwa, D., Robb, J.R., Heglund, P.J. 2017. Forging the future: a guide to implementing adaptive management in the National Wildlife Refuge System. Falls Church (VA): U.S. Fish and Wildlife Service, National Wildlife Refuge System. 64 pp. Kushlan, J., M. Steinkamp, K. Parsons, J. Capp, M. Cruz, M. Coulter, I. Davidson, L. Dickson, N. Edelson, R. Elliot, R. Michael Erwin, S. Hatch, S. Kress, R. Milko, S. Miller, K. Mills, R. Paul, R. Phillips, J. Saliva, B. Sydeman, J. Trapp, J. Wheeler, and K. Wohl. 2002. Waterbird Conservation for the Americas: The North American Waterbird Conservation Plan, Version 1. Longcore, J.R., D.G. McAuley, G.R. Hepp, and J.M. Rhymer (2000). American Black Duck (Anas rubripes), version 2.0. In The Birds of North America (A.F. Poole and F.B. Gill, Editors). Cornell Lab of Ornithology, Ithaca, NY, USA. https://doi.org/10.2173/bna.481. Macwhirter, R B., P. Austin-Smith Jr., and D.E. Kroodsma. 2002. Sanderling (Calidris alba), version 2.0. In The Birds of North America (A.F. Poole and F.B. Gill, Editors). Cornell Lab of Ornithology, Ithaca, NY, USA. https://doi.org/10.2173/bna.653. McDowell, C. 2017. Marsh sediment accumulation and accretion on a rapidly retreating estuarine coast (M.S thesis). University of Delaware. https://pdfs.semanticscholar.org/0c8d/48e865b0f20a53e9a81d17a901de52ddb9c8.pdf. McShea, W.J., and J.H. Rappole. 2000. Managing the Abundance and Diversity of Breeding Bird Populations through Manipulation of Deer Populations. Conservation Biology 14(4): 1161-1170. NatureServe. 2018. NatureServe Explorer: An online encyclopedia of life [web application]. Version 7.1. NatureServe, Arlington, Virginia. Available http://explorer.natureserve.org. (Accessed: October 18, 2018). North Atlantic Landscape Conservation Cooperative (NALCC). 2017. Nature’s Network. 2017-05-03 (data creation). Terrestrial Ecosystem Core Areas, Unstratified. Northeast U.S. Online at: http://www.naturesnetwork.org/. Nikitina, D.L., Pizzuto, J.E., Schwimmer, R.A., and Ramsey K.W., 2000, An updated Holocene sea-level curve for the Delaware coast, Marine Geology, 171, 17-20. Northeast Partners in Amphibian and Reptile Conservation (NEPARC). 2010. Northeast Amphibian and Reptile Species of Regional Responsibility and Conservation Concern. Publication 2010-1. Palmer, W.E., T.M. Terhune, and D.F. McKenzie (eds). The National Bobwhite Technical Committee. 2011. The National Bobwhite Conservation Initiative: A range-wide plan for recovering bobwhites. National Bobwhite Technical Committee Technical Publication, ver. 2.0, Knoxville, TN. Pierce, R.A., W. White and P. Graham. Revised 2008. Missouri Bobwhite Quail Habitat Appraisal Guide. University of Missouri Extension Service Publication MP902, 2005. Online at: https://extensiondata.missouri.edu/pub/pdf/miscpubs/mp0902.pdf. Poole, A.F., P.E. Lowther, J.P. Gibbs, F.A. Reid, and S.M. Melvin (2009). Least Bittern (Ixobrychus exilis), version 2.0. In The Birds of North America (A.F. Poole, Editor). Cornell Lab of Ornithology, Ithaca, NY, USA. https://doi.org/10.2173/bna.17.

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Ringleman, J., Anderson, K., Babcock, K. Bliss, D., Boomer, S., Case, D., Clark, B., Coppen, J., Dickson, K., Eadie, J., Goad, D., Humburg, D., Johnson, F., Johnson, M., Koneff, M., Mott, S., Raedeke, A., Smith, D., Soulliere, G., and S. Williams. 2012a. North American Waterfowl Management Plan 2012: People Conserving Waterfowl and Wetlands. Rooney, T.P. and D.M. Waller. 2003. Direct and indirect effects of white-tailed deer in forest ecosystems. Forest Ecology and Management 181(1):165-176. Rosenberg, K.V., J.A. Kennedy, R. Dettmers, R.P. Ford, D. Reynolds, J.D. Alexander, C.J. Beardmore, P.J. Blancher, R.E. Bogart, G.S. Butcher, A.F. Camfield, A. Couturier, D.W. Demarest, W.E. Easton, J.J. Giocomo, R.H. Keller, A.E. Mini, A.O. Panjabi, D.N. Pashley, T.D. Rich, J.M. Ruth, H. Stabins, J. Stanton, T. Will. 2016. Partners in Flight Landbird Conservation Plan: 2016 Revision for Canada and Continental United States. Partners in Flight Science Committee. Rosenberg, K.V., D. Pashley, B. Andres, P.J. Blancher, G.S. Butcher, W.C. Hunter, D. Mehlman, A.O. Panjabi, M. Parr, G. Wallace, and D. Wiedenfeld. 2014. The State of the Birds 2014 Watch List. North American Bird Conservation Initiative, U.S. Committee. Washington, DC. Available online at: http://abcbirds.org/birds/watchlist/. Rush, S.A., K.F. Gaines, W.R. Eddleman, and C.J. Conway (2018). Clapper Rail (Rallus crepitans), version 2.1. In The Birds of North America (P.G. Rodewald, Editor). Cornell Lab of Ornithology, Ithaca, NY, USA. https://doi.org/10.2173/bna.clarai11.02.1. Salas, D. and M. Pranckus. 2015. ROCSTAR: Resources of Concern Selection Tool for America’s Refuges. Cardno. Fitchburg, Wisconsin. Unpublished Report-37596. Smith EF and Others. 1994. Water Management Plan for Bombay Hook NWR. Smith EF and Others. 1994. Marsh and Water Management Plan Bombay Hook National Wildlife Refuge. Steinkamp, M. 2008. New England/Mid-Atlantic Coast Bird Conservation Region (BCR 30) Implementation Plan. Taylor, J.D. and Paveglio F.L., 2017. Identifying resources of concern and management priorities for a Refuge: a handbook. Washington, DC: U.S. Fish and Wildlife Service. 74 pp. United States National Vegetation Classification (USNVC). 2017. United States National Vegetation Classification Database, V2.01. Federal Geographic Data Committee, Vegetation Subcommittee, Washington, DC. Accessed on 14 August 2018 at http://usnvc.org/explore-classification/ U.S. Census Bureau 2018. Quick Facts: Delaware and Kent County. Accessible online at: https://www.census.gov/quickfacts/fact/table/de,kentcountydelaware/PST045217. U.S. Department of Agriculture. 2017. State Agriculture Overview: Delaware. U.S. Fish and Wildlife Service (USFWS). 2018. U.S. Fish and Wildlife Service Manual. Available online at http://www.fws.gov/policy/manuals/. U. S. Fish and Wildlife Service (USFWS). 2018. Aquatic Connectivity in the Northeast Region – Strategic Plan 2018, Hadley, Massachusetts. 22 pp. U.S. Fish and Wildlife Service (USFWS). 2017. Strategic Plan Update: Migratory Bird Program. September. U.S. Fish and Wildlife Service (USFWS). 2012. North American Waterfowl Management Plan Action Plan: A Companion Document to the North American Waterfowl Management Plan. December.

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U.S. Fish and Wildlife Service (USFWS). 2011. Birds of Management Concern and Focal Species. November. U.S. Fish and Wildlife Service (USFWS). 2010. Strategic Plan for Responding to Accelerating Climate Change. September. U.S. Fish and Wildlife Service (USFWS). 2010b. Application of the Sea-Level Affecting Marshes Model (SLAMM 6) to Bombay Hook NWR. 13 February. U.S. Fish and Wildlife Service (USFWS) 2008. Birds of Conservation Concern. U.S. Fish and Wildlife Service (USFWS). 2008. Strategic Habitat Conservation Handbook: A Guide to Implementing the Technical Elements of Strategic Habitat Conservation (Ver 1.0). Report from the National Technical Assistance Team. 22 pp. U.S. Fish and Wildlife Service (USFWS) 2004. Migratory Bird Program Strategic Plan. Available online at: http://www.fws.gov/migratorybirds/AboutUS.html. U.S. Fish and Wildlife Service (USFWS). Undated. Bombay Hook National Wildlife Refuge – Birds. 2 pp. U.S. Fish and Wildlife Service (USFWS). Undated. Bombay Hook National Wildlife Refuge – Mammals. 5 pp. U.S. Fish and Wildlife Service (USFWS). Undated. Bombay Hook National Wildlife Refuge – Amphibians and Reptiles. 4 pp. U.S. Fish and Wildlife Service (USFWS). Undated. Invertebrates of Bombay Hook National Wildlife Refuge – A Partial List. 6 pp. Watts. 1999. Bird Conservation Plan for the Mid-Atlantic Coastal Plain Physiographic Area. Williams, B.K., R.C. Szaro, and C.D. Shapiro. 2009. Adaptive management: the U.S. Department of the Interior technical guide. Adaptive Management Working Group, U.S. Department of the Interior, Washington, DC. Wurster, F.C., K.J. Hunt, and R.E. Burns. 2013. Water Resources Inventory and Assessment: Bombay Hook National Wildlife Refuge, Smyrna, DE. 26 February.

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APPENDIX A. DRAFT ENVIRONMENTAL ASSESSMENT FOR THE IMPLEMENTATION OF THE HABITAT MANAGEMENT PLAN AT BOMBAY HOOK NATIONAL WILDLIFE REFUGE

Appendix A. Environmental Assessment 1 August 2020 Habitat Management Plan for Bombay Hook National Wildlife Refuge

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Appendix A. Environmental Assessment 2 August 2020 Habitat Management Plan for Bombay Hook National Wildlife Refuge

Environmental Assessment for the Bombay Hook National Wildlife Refuge Habitat Management Plan

Date: August 17, 2020 This Environmental Assessment (EA) is being prepared to evaluate the effects associated with this proposed action and complies with the National Environmental Policy Act (NEPA) in accordance with Council on Environmental Quality regulations (40 CFR 1500-1509) and Department of the Interior (43 CFR 46; 516 DM 8) and U.S. Fish and Wildlife Service (550 FW 3) regulations and policies. NEPA requires examination of the effects of proposed actions on the natural and human environment. Proposed Action: The U.S. Fish and Wildlife Service (Service) has completed this Environmental Assessment (EA) for the Habitat Management Plan (HMP) for Bombay Hook National Wildlife Refuge (NWR). The Service has prepared the HMP, which is incorporated herein by reference and contains this EA, to provide more details regarding the Proposed Action for habitat management on the refuge. The Service discloses anticipated effects for each alternative, pursuant to the NEPA of 1969, as amended. Where possible, the HMP aligns with State conservation priorities outlined in the Delaware State Wildlife Action Plan (DNREC 2015). Combined, these efforts provided clarity about the desired future conditions we aim to protect, enhance, and/or restore on the refuge for the benefit of trust resources over the next 15 years. Two alternatives were prepared for this EA: a No Action Alternative and a Proposed Action Alternative. For details on the specific components and actions constituting the alternatives, see the ‘Alternatives Considered’ section of this EA. The draft Proposed Action Alternative may be modified between this draft and the final EA depending on the comments received from the public and other agencies and organizations. The Service’s Regional Refuge Chief for Interior Region 1 will decide which alternative will be implemented. Should the Service decide to implement the HMP, the analysis in this EA will inform the decision of whether a Finding of No Significant Impact (FONSI) can be reached. The FONSI would identify the alternative selected for implementation and the rationale behind the decision. If a FONSI cannot be reached, an Environmental Impact Statement (EIS) would be prepared. Background: National wildlife refuges are guided by the mission and goals of the National Wildlife Refuge System (Refuge System), the purposes of an individual refuge, Service policy, and laws and international treaties. Relevant guidance includes the National Wildlife Refuge System Administration Act of 1966, as amended by the National Wildlife Refuge System Improvement Act of 1997, Refuge Recreation Act of 1962, and selected portions of the Code of Federal Regulations (CFR) and Fish and Wildlife Service Manual (FW). The mission of the Refuge System, as outlined by the National Wildlife Refuge System Administration Act (NWRSAA), as amended by the National Wildlife Refuge System Improvement Act (Refuge Improvement Act; 16 U.S.C. 668dd et seq.), is to: “... to administer a national network of lands and waters for the conservation, management and, where appropriate, restoration of the fish, wildlife, and plant resources and their habitats within the United States for the benefit of present and future generations of Americans” Bombay Hook NWR, located in Kent County, Delaware, was established pursuant to Executive Order 7643 in 1937 (2 CFR 1305), under authority of the Migratory Bird Conservation Act of 1929 (MBCA; 16

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U.S.C. 715d). The primary purpose of the refuge is “…for use as an inviolate sanctuary, or for any other management purpose, for migratory birds” (MBCA). Consisting of 16,162 acres, the refuge is comprised of coastal marsh, forested, freshwater wetland, grassland, and shrubland communities that support a variety of migratory birds and resident wildlife. The refuge prepared this HMP to guide management actions of habitat for a period of 15 years. Purpose and Need for the Proposed Action: The purpose of the HMP is to provide a strategic, operational guide-to-guide strategic habitat management that will benefit migrating and wintering waterfowl, migrating shorebirds, salt marsh specialist species, and other species of conservation concern on the refuge. The need for this Proposed Action is to meet the Service’s priorities and mandates as outlined by the Refuge Administration Act, as Amended by the Refuge System Improvement Act of 1997. The Administration Act directs the Service to ensure that the biological integrity, diversity, and environmental health of the Refuge System are maintained for the benefit of present and future generations of Americans. To meet this mandate, the Service developed their Biological Integrity, Diversity, and Environmental Health Policy (BIDEH) to provide refuges with guidance for consideration and protection of the broad spectrum of native fish, wildlife, and habitat resources on refuges and in associated ecosystems. This policy provides refuges with a process for evaluating the best management direction to prevent the additional degradation of environmental conditions and to restore lost or severely degraded environmental components. In evaluating these factors, the Service looks at historic conditions and compares them to the current ones. This provides a benchmark of comparison for the relative intactness of ecosystems' functions and processes, as well as an assessment of the opportunities and limitations to restoring biological integrity, diversity, and environmental health. Alternatives Considered Alternative A: Current Management (No Action Alternative) The No Action Alternative is carried forward in this EA in accordance with 40 CFR 1502.14(d) to represent the environmental baseline against which to compare the impacts of the Proposed Action. The No Action Alternative represents a continuation of existing conditions, which includes the implementation of various management activities but represents a lack of formal, comprehensive management direction, which leaves the refuge open to inconsistencies, identified threats, uncertainties, and other risks. Habitat management has been limited to manipulation of water levels in the large freshwater impoundments, mowing fields used for goose hunting, and allowing natural succession on the most marginal (wet) former agricultural fields. Management would continue to be guided by separate, previously approved plans (HMP 1.4.3) that address management of marsh and water, open fields, forest, and fire. Because these separate plans span a large timeframe in their development, they did not always provide consistent management direction or cohesive management objectives, as management priorities and available science were changing over time. Alternative B: Strategic Habitat Management (Proposed Action) The HMP identifies goals and objectives aimed at supporting key life cycle requirements of priority resources of concern, as well as their required habitat. The HMP goals to provide strategic habitat management on the Refuge are as follows: Goal 1. Forested Habitats – Perpetuate and, where feasible, restore the biological integrity, diversity, and environmental health of refuge upland and wetland forests that benefit priority resources of concern. Goal 2. Freshwater Wetland Habitats – Maintain the biological integrity, diversity, and environmental health of the freshwater wetland habitats surrounding and within the

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Refuge’s wetland impoundments, ponds, and moist soil units, with seasonal management that benefits priority resources of concern. Goal 3. Coastal Salt Marsh Habitats – Perpetuate and restore the biological integrity, diversity, and environmental health of the refuge’s tidal salt marsh and associated tidal shrub and beach habitats to benefit priority resources of concern. Diminish marsh loss and pursue restoration, where appropriate, to ensure natural sustainability. Goal 4. Early Successional Upland Habitats – Maintain and/or enhance the vegetation, biological integrity, diversity, and environmental health of the refuge’s early successional habitats that benefit priority resources of concern. Objectives to support each of these four goals were developed as well. Under this alternative, the refuge would re-establish larger blocks of Coastal Plain forest and continue exploring management options for increasing the resiliency of its vulnerable coastal habitats. Specifically, the refuge would: • Expand the coverage area and enhance the quality of the refuge’s forested wetlands, one of the most imperiled habitats in the Delmarva Peninsula. o Passively allow natural succession to convert approximately 275 acres of former early successional habitat to forested wetland. o Actively convert early successional and upland areas through common restoration actions (e.g., plugging ditches, supplemental planting, aggressive invasive species spot control, and regenerating hardwood species). o Create isolated shallow waters or vernal pools by excavating earthen ditch plug material from unique sites.

• Enhance the quality of the refuge’s upland forest, one of the most imperiled habitats in the Delmarva Peninsula. o Passively allow natural succession to convert approximately 615 acres of early and mid- successional upland forest to mature upland forest. o Intensify invasive species spot control via physical, chemical, and biological treatments (HMP 1.2.3). o Actively improve forest structure as needed using supplemental planting.

• Protect the biological integrity of the refuge’s existing wetland impoundments and expand acreage of smaller impoundments, while also developing an impoundment management strategy. o Increase the treatment of invasives using prescribed fire, and other tools that become available (e.g., biological control). o Create about 20 acres of new, small, seasonally managed impoundments. o Implement sea level rise protection measures including, but not limited to, dike stabilization, impoundment deposition, or marsh restoration. o Maintain, replace, or repair existing infrastructure, as appropriate (i.e., water control structures, dikes, and other infrastructure that help sustain management of impounded areas).

• Maintain the biological integrity of the refuge’s vast tidal salt marsh, while also developing a tidal salt marsh management strategy to consider a reasonable range of management and restoration activities. o Reduce common reed from priority areas and use early detection rapid response (EDRR) to prevent expanded or new infestations. o Consider thin layer deposition projects to offset sea level rise impacts

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o Consider restoration of historic hydrology to areas of human-caused disturbance (mosquito ditching). o Identify, evaluate, prioritize, and implement other sea level rise protection measures, such as managing tidal marsh transgression on refuge-managed lands.

• Enhance the quality of the refuge’s early successional habitat, concentrating this disturbance- dependent natural habitat type near the refuge headquarters area (where there is high visitor use), as well as at Fisher Tract and Steamboat Landing. o Focus planting and seeding efforts of native grasses, especially native flowering nectar plants. o Focus invasive species treatments for priority populations of invasive species. o Install annual forage species (e.g., clover) on up to 80 acres of grassland annually to supplement foraging needs for migratory waterfowl, the northern bobwhite quail, and to compensate for grassland habitat losses to shrubland succession or forest restoration o Passively allow natural succession to convert former early successional habitat to forested wetlands and upland forests. More information on the goals and objectives can be found in Chapter 4 of the HMP. To avoid conflicts, we would complete additional administrative requirements prior to implementing activities not fully analyzed in this EA, including but not limited to: • Consultation with the Regional Historic Preservation Officer (RHPO) and State Historic Preservation Officer (SHPO) to ensure compliance with the National Historic Preservation Act (NHPA) Section 106 for the protection of historic properties.

• Employ best management practices and comply with permitting requirements (e.g., USACE Section 404 permitting).

• Seek concurrence for Coastal Zone Management Act Consistency Determination upon approval of FONSI and final HMP. This alternative meets the purpose and need for generating an approved plan that, when implemented, helps achieve the refuge purpose, fulfills the Refuge System’s mission, and complies with all applicable laws, regulations, and policies governing the management of Service lands. The HMP provides comprehensive management direction, along with identifying clear metrics for assessing what successful conservation delivery looks like at Bombay Hook NWR for the next 15 years. Alternatives Considered, But Dismissed From Further Consideration The Planning Team considered the evaluation of a separate “intensive management” alternative, which would increase the involvement, frequency, and number of management actions across all habitats. This alternative represents a scenario where increased or unlimited resources (funding, staff, or partners) would be available to more rapidly achieve (or exceed) the objectives of all Refuge habitats simultaneously. Because the refuge operates at a relatively constant and predictable level of allocated resources, this alternative was determined by the Planning Team to be unrealistic. Affected Environment The refuge consists of approximately 16,162 acres in Kent County, Delaware (see HMP Figure 1-1) providing a diversity of upland and wetland habitats for migrating and wintering waterfowl, migrating shorebirds, salt marsh specialist species, and other species of conservation concern. Bombay Hook NWR is relatively flat, with most habitat less than 10 feet in elevation. Seventy-five percent of the refuge consists of tidal salt marsh intersected by winding rivers, guts, and creeks. Landward of the marsh are forests, freshwater wetlands, grasslands, and shrubland communities. The refuge is bordered by

Appendix A. Environmental Assessment 6 August 2020 Habitat Management Plan for Bombay Hook National Wildlife Refuge

agricultural lands to the west, salt marsh communities to the north and south, and the Delaware Bay to the east. The HMP Section 2.0 (Existing Conditions) summarizes pertinent refuge background information, including a description of existing conditions such as, physical environment (water quality, topography and soils, geology and hydrology, climate, and air quality); the biological environment (terrestrial, wetland, and aquatic habitats, and fish and wildlife); the socioeconomic environment (geographic setting, history and archaeology, land use, and recreational use); historic and current ecosystem influences; and current threats. This analysis is not encyclopedic, and information is streamlined to inform the development of appropriate future management actions. Environmental Consequences of the Action This section analyzes the environmental consequences of the action on each affected resource, including direct and indirect effects. This EA only includes the written analyses of the environmental consequences on a resource when the impacts on that resource could be more than negligible and therefore considered an “affected resource” or are otherwise considered important as related to the proposed action. Any resources that would not be more than negligibly impacted by the action have been dismissed from further analysis (Table A-1). The following section contains: 1. A brief description of the affected resources in the proposed action area;

2. Impacts of the proposed action and any alternatives on those resources, including direct and indirect effects.

3. A brief description of the past, present, and reasonably foreseeable other actions affecting these resources, and the cumulative impacts of the proposed action and any alternatives. Impact Types: • Direct effects are those that are caused by the action and occur at the same time and place.

• Indirect effects are those that are caused by the action and are later in time or farther removed in distance, but are still reasonably foreseeable.

• Cumulative impacts result from the incremental impact of the action when added to other past, present, and reasonably foreseeable future actions regardless of what agency (Federal or non- Federal) or person undertakes such other actions.

Table A-1. Potential for adverse impacts from proposed action and the alternative. See Chapter 4 of the HMP for more detail regarding anticipated impacts on resources.

Resources Not Applicable: No/Negligible Greater than Resource does not exist Impacts: Exists but no Negligible Impacts: in project area or negligible impacts Impacts analyzed in this EA

Wildlife and Aquatic ☐ ☐ ☒ Species

Threatened and ☐ ☐ ☒ Endangered Species

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and Other Special Status Species

Vegetation ☐ ☐ ☒ Wetlands ☐ ☐ ☒ Geology and Soils ☐ ☒ ☐ Air Quality ☐ ☒ ☐ Wilderness* ☐ ☒ ☐ Visitor Use and ☐ ☐ ☒ Experience

Cultural Resources* ☐ ☒ ☐ Land Use ☐ ☐ ☒ Refuge Management ☐ ☒ ☐ and Operations

Environmental Justice ☐ ☒ ☐ *Although these resources were determined to have negligible impacts, for compliance with the National Historic Preservation Act (Section 106) and the Wilderness Act of 1964, all resources were identified and any potential impacts were addressed. Additionally, in compliance with Section 106, actions identified within the EA will be consulted with the SHPO prior to implementation.

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Table A-2. Affected Natural Resources and Anticipated Impacts of the Alternatives. Affected Resource / Existing Condition Potential Direct and Indirect Impacts Wildlife and Aquatic Species Alternative A: (HMP Section 2.6) The ongoing management of refuge habitat is generalized to each The refuge supports a diversity of land cover and does not specifically designate focal species and game and non-game wildlife species manage toward ecosystem attributes specifically benefitting them. across 7 broad habitat types, Existing management outcomes are generally limited to single including 278 species of birds, 35 species (i.e., invasive species spot treatment) without defined long- species of mammals, 35 species of range targets. The refuge would continue to meet its mandate as reptiles and amphibians, and diverse stewards to Trust resources, but may not optimize management but largely uninvestigated efforts that benefit a range of species assemblages. populations of fish and invertebrates. Because this alternative does not consider a landscape-scale approach to threat mitigation, certain habitats and species may be vulnerable to the incremental impacts of threats, such as sea level rise, coastal erosion, and subsidence. Alternative B (Proposed): The strategic, adaptive approach to land management outlined in the HMP and the prioritization of habitats would streamline available resources to maximize benefits of management efforts. The specific, measurable, science-based ecosystem endpoints are tied specifically to resources of concern (ROC) requirements (i.e., HMP Table 3-2) and are designed to promote ecosystem health in support of priority ROC, other candidate ROC, and associated wildlife (i.e., HMP Table 3-3). We anticipate that the Proposed Action would increase the dependability of the refuge as a sanctuary for target resident and migratory wildlife and aquatic species; would support the recovery, stabilization, or growth of target populations; and would promote the resiliency and adaptability of required habitats in the face of climate change and other ecosystem threats.

Potential minor adverse impacts may occur to some species as certain habitats are transitioned across the refuge. Specifically, populations of pollinators and other early successional uplands- obligate species may decline as the gradual transition of 223 acres of such habitat to forested wetland occurs. However, adverse impacts may be offset to some degree by the increase in field habitat value and quality through proposed management actions to increase diversity and extend available bloom in remaining locations. Likewise, the transition of 48 acres of upland forest to forested wetland is likely to benefit both upland and wetland forest- dwelling species as larger blocks of contiguous, mature forest ecosystem are established.

Consideration and planning for threats (e.g., HMP Figure 2-5) through adaptive management techniques would be implemented to either actively reduce threat risk, actively reduce threat effect, or assist in gradual transition to a new existing condition as unavoidable threats progress. For example, focusing on diversity in

Appendix A. Environmental Assessment 9 August 2020 Habitat Management Plan for Bombay Hook National Wildlife Refuge

Affected Resource / Existing Condition Potential Direct and Indirect Impacts plantings may help habitats maintain resiliency or adapt to changing climatic conditions. Threatened and Endangered Alternative A: Species and Other Special Status No appreciable change to existing condition anticipated. Species(HMP Section 2.6.6) Alternative B (Proposed): There are no known federally listed Red knot and pied-billed grebe: Improvement of impoundment and threatened/endangered species that associated wetland habitat management (e.g., structured invasive breed on the refuge. species control and prioritization of water management) may improve habitat quality and use by red knot and pied-billed grebe Federally threatened red knots during migration. (Calidris canutus) are known to use refuge impoundments and limited American kestrel: Potential negligible to discountable adverse beach habitats during migration, indirect impact from the transition of 223 acres of early although not consistently or in large successional upland habitat to forested wetland; however, loss in numbers. available acreage supporting prey-species may be offset by the increase in field habitat value and quality through proposed State listed endangered species management actions that may increase prey species abundance. documented as nesting on the refuge include American kestrel (Falco Forster’s tern and northern harrier – Potential minor beneficial sparverius), Forster’s tern (Sterna indirect impact as tidal salt marsh habitat is managed to preserve forsteri), northern harrier (Circus and restore habitat integrity. cyaneus), pied-billed grebe (Podilymbus podiceps), and sedge Sedge wren: Potential minor beneficial indirect impacts as wetland wren (Cistothorus stellaris). acreage, function, and value are increased across the refuge. Systematic focus on invasive species eradication may increase available habitat as Phragmites is removed and native grasses are released to provide quality-nesting habitat. Vegetation(HMP Chapter 3) Alternative A: Bombay Hook NWR consists of No change to existing condition anticipated. Common reed and coastal, forested, freshwater, other invasive species would continue to be spot-treated reactively grassland, and shrubland habitats. rather than under a proactive, systematic adaptive management Approximately 77 percent of the approach. Forests on the refuge would not be actively managed and refuge is tidal salt marsh with the supporting diversity and value of grassland and shrubland habitats remaining uplands currently would continue to require extensive invasive plant species control maintained as grassland/shrubland and native planting efforts. and forests. Alternative B (Proposed): In general, native target vegetation species would benefit from the Vegetation composition and structure is largely influenced by water level in Proposed Action, as it is intended to increase the natural attributes the Delaware Bay and, to some of all ecosystems and reduce impacts of and risks from known extent, by storms and shifting sand. threats, such as presence of invasive species. The Proposed Action sets the stage for increased occurrence and health of core forested Forested habitat is exceptionally habitat into the future, and helps increase diversity. Proposed valuable habitat in the region and is management would link fragmented habitats, such as forest blocks, underrepresented in the current which improves the integrity of vegetation communities. Early landscape. The refuge contains successional habitats will be managed more deliberately, to nearly 900 acres of woodlands; improve vegetation community diversity and quality and reduce the however, most stands are severely presence of invasive species. Wetland vegetation communities would continue to be protected, and where feasible, expanded or

Appendix A. Environmental Assessment 10 August 2020 Habitat Management Plan for Bombay Hook National Wildlife Refuge

Affected Resource / Existing Condition Potential Direct and Indirect Impacts fragmented and over half are less restored. The Proposed Action would not impact vegetation of than 10 acres in size. special management concern.

Wetlands(HMP Table 2-3) Alternative A: Bombay Hook NWR is over 86 No change from existing condition anticipated. percent wetland, with 12,786 acres of Alternative B (Proposed): tidal salt marsh, 793 acres of forested Over time, forested wetland habitat would increase by 277 acres, wetland, and 302 acres of semi- but freshwater wetland habitat would decrease by 23 acres, for a permanent freshwater wetland. total net gain of 254 acres of wetlands across the refuge. Health and function of all wetland systems, and value to migratory bird species and amphibians, would improve due to strategic focus on hydrologic restoration and invasive species control. Geology and Soils (HMP Section Alternative A: 2.8 and 2.9) As the elevation of the refuge generally does not exceed 10 feet Bombay Hook NWR is found in the above sea level, and because the majority of the refuge is directly Atlantic Coastal Plain of Delaware adjacent to the Delaware Bay shoreline, subsidence coupled with and is part of a larger geological climate change and severe weather could provoke significant structure known as the Atlantic ecosystem shifts if salt or brackish water intruded further inland. As Coastal Plain-Continental Shelf summer temperatures are projected to increase as a result of climate Geosyncline. This structure is known change, the duration of seasonal inundation and stable water levels to be sinking, relative to adjacent could be lessened, resulting in the drying of soils. land at a rate of 1.7 mm/year. The Alternative B (Proposed): Same as No Action Alternative shoreline of the entire lower Delaware Bay is migrating in a landward direction due to subsidence, sea level rise, and coastal erosion; and the effects of these three processes are observable on the refuge (Holdahl and Morrison 1975). Seventy-nine percent of the soils on the refuge are hydric and tend to be composed of peat and mucky silt loams. They are flooded frequently and have a relatively unconsolidated structure. Wilderness Alternative A: Although approximately 2,000 acres No change from existing condition anticipated. In accordance with at Bombay Hook NWR became the Wilderness Act and Service policies, the refuge’s proposed proposed wilderness in 1975 wilderness area would continue to be managed as if designated (USFWS 1975; 30 FR 47242), wilderness. Its wilderness character and values of the proposed Congress has not yet taken any steps wilderness would continue to be protected and monitored. to designate wilderness within the Alternative B (Proposed): Same as No Action Alternative refuge.

Appendix A. Environmental Assessment 11 August 2020 Habitat Management Plan for Bombay Hook National Wildlife Refuge

Table A-3. Affected Human Environment and Anticipated Impacts of the Alternatives. Affected Resource/Existing Condition Potential Direct and Indirect Impacts Visitor Use and Experience (HMP Alternative A: Section 2.10) No change from existing condition anticipated. The refuge would The refuge is open for nature continue to manage habitats for the greatest benefit to wildlife, photography, wildlife observation, which would continue to support wildlife-dependent recreation. The environmental education, and refuge would continue to manage all assets that support recreation interpretation. Amenities include a activities, such as the visitor center, roads, trails, and observation visitor center, boardwalk, 12-mile towers, to the greatest beneficial use and for the continued health round-trip wildlife drive, five nature and safety of all users. We anticipate that as the population trails, and three 30-foot observation continues to grow, and wild areas become increasingly scarce in the towers. landscape, the refuge would continue to support a gradual but consistent increase of visitors through time. In March 2020, the refuge released a Alternative B (Proposed): Draft Hunting and Fishing Plan, In addition to the impacts of alternative A, habitat quality for providing deer and waterfowl migratory waterfowl would be enhanced and should increase the hunting, along with limited quality of the hunting and viewing experience. Enhancement and opportunities for small game, wild restoration of forested habitats should also improve the quality and turkey, and upland migratory game variety of viewing experiences for visitors. bird hunting. This proposed plan would also open two areas of the refuge to recreational fishing. This draft proposes adopting State hunting and fishing regulations for the areas open for those uses, with some additional refuge-specific regulations to minimize conflicts with other refuge objectives and visitor activities. Cultural Resources (HMP Section Alternative A: 2.11 Ongoing refuge management does not impact historic, architectural, The Allee House was placed on the archaeological, and cultural resources (including the National National Register of Historic Places Register property). Any earth moving activities associated with in 1971. The house and furnishings habitat management (i.e., mowing, prescribed fire, field were restored in 1966, the house maintenance) affect only shallow, superficial soil layers and are was stabilized again in 2016 but was unlikely to encounter unknown artifacts and are within previously not restored, leading to the Allee disturbed contexts. However, in the event an unanticipated discovery House being currently closed to the of previously unidentified archaeological resources is made in the public (Springate et al. 2011). In course of normal maintenance activities, all activities near the consultation with the Delaware State discovery would stop and all reasonable measures would be taken to Historic Preservation Officer avoid or minimize harm to the property until the Service concludes (SHPO), the Service determined that consultation with the SHPO. In 2015, the Service entered into a the six remaining structures of the Memorandum of Agreement (MOA) with the SHPO regarding original Headquarters Complex mitigation measures for the adverse effects of the demolition of the were determined eligible for listing Vehicle Maintenance Shop. on the National Register of Historic Places. These six structures There are no known Indian Trust Resources on the refuge or the comprise the Headquarters Complex nearby area; therefore, there are no anticipated impacts on such Historic District and include; the resources.

Appendix A. Environmental Assessment 12 August 2020 Habitat Management Plan for Bombay Hook National Wildlife Refuge

Affected Resource/Existing Condition Potential Direct and Indirect Impacts Administration Alternative B (Proposed): Building/Maintenance Shop, the Coordination with the SHPO is not applicable at this time. Should Vehicle Maintenance Shop, the additional projects tiered from the HMP require earth moving Refuge Manager’s House, the activities or affect known historic properties, further coordination Patrolman’s House, the Equipment with the SHPO and potentially interested tribes would occur. For Shed, the Oil House, and the example, breaching or plugging of existing water control structures Storage Barn. or excavation to establish vernal pools may trigger additional environmental review under NEPA and Section 106 of the NHPA. The two Federally recognized Tribes with interests in Delaware are There are no known Indian Trust Resources on the refuge or the the Delaware Nation and Delaware nearby area; therefore, there are no anticipated impacts on such Tribe of Indians. There are no resources. known Indian Trust Resources on the refuge or the nearby area.

Land Use Alternative A: Refuge land use and land cover is Although the refuge would continue to uphold its responsibilities as predominantly utilized as described a steward of trust resources and fulfill its designated mission, in the Wildlife, Vegetation, and without a long-term strategy that identifies threats and prioritizes Recreation sections above. There are resources and strategies, achievement of habitat goals and objectives no active leases or for the effective longer-term function of refuge ecosystems may be consumptive/extractive uses of at risk from inconsistencies in potential funding and other threats. refuge land. Habitats would persist, but the refuge may not be able to support designated land use to be the most effective for and greatest value to identified ROC. Alternative B (Proposed): The refuge would continue to uphold its responsibilities as a steward of trust resources and fulfill its designated purpose and the Refuge System’s mission. The HMP will provide an approved long-term strategy that identifies habitat goals and objectives for the effective longer-term function of refuge ecosystems, while simultaneously identifying threats, prioritizing resources, and determining appropriate management strategies. The biological integrity, diversity, and environmental health of wildlife habitats would continue to be protected, enhanced, and/or restored to support identified ROC. The desired endpoint is management efficiency and land use optimization for all targeted ROC.

Environmental Justice Alternative A: Executive Order 12898, Federal No change from existing condition anticipated. The refuge does not Actions to Address Environmental disproportionally impact minority or low-income populations; Justice in Minority Populations and rather, the refuge provides a low-cost nature experience to all Low-Income Populations, requires visitors and strives to be a good neighbor in the local community. all Federal agencies to incorporate Alternative B (Proposed): Same as No Action Alternative environmental justice into their missions by identifying and addressing disproportionately high or adverse human health or environmental effects of their

Appendix A. Environmental Assessment 13 August 2020 Habitat Management Plan for Bombay Hook National Wildlife Refuge

Affected Resource/Existing Condition Potential Direct and Indirect Impacts programs and policies on minorities and low-income populations and communities.

Table A-4. Anticipated Cumulative Impacts of the Alternatives. Other Past, Present, and Reasonably Foreseeable Activity Impacting Affected Environment Descriptions of Anticipated Cumulative Impacts Regional Plans Bombay Hook NWR is situated along Bombay Hook NWR is currently managed as the Coastal Delaware the Delaware Bay and within the Complex with Prime Hook NWR. Bombay Hook is approximately 40 Atlantic Flyway migration corridor. miles North of Prime Hook, and shares administrative resources In December 2016, the Delaware (such as personnel and equipment). The Coastal Delaware Complex River Basin Conservation Act was falls within the Delaware River Basin Restoration Program, and signed into law, establishing the consequently, the refuge works in coordination with other Federal, Delaware River Basin Restoration State, and local governments to improve the ecological integrity of Program. The mission of this the Refuge within the Delaware River Basin. program is to bring Federal, State, and local governments together to Implementation of the HMP will bring a science-driven framework to identify, prioritize, and implement aid in the strategic pursuit of defining and implementing conservation restoration activities within the basin. priorities for sustainable landscapes. Strategic Habitat Conservation The mission of the program is to (SHC) involves both cross-programmatic Service groups and non- improve ecological integrity Service conservation partners. Within the limits of established throughout the basin, and in so doing, regulations, and policies, the refuge will support a unified and improve the economic health and coordinated approach generated by the Service, States, and quality of life for all citizens in the conservation partners to provide important migratory stopover and watershed. wintering area for both waterfowl and shorebirds in the Atlantic Flyway. Additionally, the refuge will also work in coordination with In August 2018, the National Fish other members of the Delaware River Basin Restoration Program to and Wildlife Foundation launched the achieve strategic habitat conservation. Delaware Watershed Conservation Fund in partnership with the Service. The HMP will continue to bring Bombay Hook into the folds of The fund represents the first step in regional strategic habitat conservation – focusing on species of implementing a strategy developed greatest conservation need and regional priority habitats. by partners with guidance from the Service to focus conservation in four key areas: clean water, habitat, recreation, and flow management.

At the regional level, Bombay Hook NWR plays a dominant role as part of the North Atlantic planning region within the Atlantic Flyway migration corridor. The Atlantic Flyway encompasses some of the hemisphere’s most productive

Appendix A. Environmental Assessment 14 August 2020 Habitat Management Plan for Bombay Hook National Wildlife Refuge ecosystems, including forests, beaches, and coastal wetland.

Bombay Hook NWR is considered to have regionally crucial core habitat, which fortunately is connected through various natural corridors to other core habitats which are also protected (HMP Table 1-1). Bombay Hook NWR is an important migratory stopover and wintering area for both waterfowl and shorebirds in the Atlantic Flyway. It was named a Ramsar Wetland Site of International Importance (1992) and an Audubon Society Important Bird Area of the Delaware Bay (2000).

Projects Bombay Hook NWR is in the process The current multi-purpose building is adjacent to the proposed of building a new multi-purpose location and will have a final footprint of 7,300 square feet. Per building and demolishing two older Service policy, the current building (4,400 square feet, along with the refuge buildings. The new building DelBay ES building (1,865 square feet.), and an office trailer at will be 7,300 square feet, and will be Prime Hook NWR will be demolished so the final foot print of the built adjacent to where the new building and attendant features (e.g., parking area) will be demolished buildings were located. mitigated. The existing parking areas will continued to be used for visitor The HMP will reduce the refuge’s acreage of early successional parking. The surrounding habitat is habitat, concentrating this disturbance-dependent natural habitat type late successional habitat. Actual near refuge headquarters, where there is high visitor use. The construction will take approximately demolished building areas will be re-vegetated to help mitigate the 8 months. The project will start in loss of early successional habitat near refuge headquarters from the late FY 2021 and finish in FY 2022. new building construction. The existing parking area will continue to be used for visitors to minimize the need to disturb any additional habitat for visitor parking.

Climate Change The refuge would use an adaptive management approach for its Bombay Hook’s mid-latitude location habitat management program, reviewing the program annually and and proximity to the Atlantic Ocean revising every 5 years (if necessary). The habitat management make the refuge particularly program can be adjusted to ensure that it does not contribute further susceptible to the effects of climate to the cumulative impacts of climate change on resident wildlife and change. Temperatures in Delaware migratory birds. To ensure sound wildlife management, the refuge have increased more than 2°F since will monitor the wildlife populations and habitat conditions. The the beginning of the 20th Century. proposed monitoring and re-evaluating will help to ensure that the Annual average precipitation is habitat management program continue to contribute to the projected to continue to increase for biodiversity and ecosystem health of the refuge, and that habitat Delaware, with the increases management activities on the refuge do not contribute to any occurring in winter and spring. cumulative impacts to habitat or wildlife from climate change, Additionally, sea level rise on population growth, and development, or local, State, or regional Delaware’s coasts has been greater wildlife management. than 1-foot-per-century due to a

Appendix A. Environmental Assessment 15 August 2020 Habitat Management Plan for Bombay Hook National Wildlife Refuge variety of factors including Alternative B was developed with a landscape perspective, where the subsidence and ocean and refuge recognizes its critical placement in the landscape, especially atmospheric dynamics. Sea level rise relative to other NWRs, core habitat, and connectors (HMP Figure has caused an increase in tidal floods 2-1 and 2-2). Enhancing the availability of quality habitat in the associated with nuisance-level region, especially the addition of larger, contiguous forest habitat impacts. Nuisance floods are events cores, would benefit migrating species, support genetic diversity, and in which water levels exceed the local provide natural areas that may be more prone to adaptation in the face threshold (set by NOAA’s National of changing climate. Weather Service) for minor impacts. As sea level has risen along the Delaware coastline, the number of tidal flood days (all days exceeding the nuisance level threshold) has also increased (Runkle et al. 2017).

Consequently, one primary concern for Bombay Hook NWR is the impacts of sea level rise on marsh elevation. This is causing marsh migration, marsh inundation, and increased mortality in forests adjacent to salt marshes. These habitat changes may dramatically reduce the amount and quality of both forest for resident wildlife and salt marsh for migratory birds that are hunted. As a result, wildlife could be forced into reduced amounts of available habitat. Concentrating birds into smaller areas also has potential to more readily allow disease to spread within overwintering waterfowl populations, resulting in increased bird mortality.

Monitoring: Refuge staff will implement the HMP. A primary component of the implementation of the HMP will include development of an Inventory and Monitoring Plan (IMP), establishment of baseline data, and establishment of procedures to evaluate effectiveness of management actions. Implementation of projects in this HMP will occur simultaneously with annual activities (e.g., water management, invasive species control) documented in the annual work plan (AWP), and both plans will be integrated with the Refuge IMP following completion of this HMP. Refuge staff will use this plan as a working document to apply adaptive management concepts. Periodic revisions are expected as projects are implemented and the response of the system is monitored. Summary of Analysis: The purpose of this EA is to briefly provide sufficient evidence and analysis for determining whether to prepare an EIS or a FONSI.

Appendix A. Environmental Assessment 16 August 2020 Habitat Management Plan for Bombay Hook National Wildlife Refuge

Alternative A – No Action Alternative The No Action Alternative means that the refuge will continue to manage the habitat following the guidance put forth by separate, previously approved plans (HMP 1.4.3) that address management of marsh and water, open fields, forest, and fire. Habitat management has been limited to manipulation of water levels in the large freshwater impoundments, mowing fields used for goose hunting, and allowing natural succession on the most marginal (wet) former agricultural fields. It is likely that the refuge would continue to uphold its responsibilities as a steward of trust resources and fulfill its designated mission; however, without a long-term strategy that identifies threats and prioritizes resources and strategies, achievement of habitat goals and objectives for the effective longer-term function of refuge ecosystems may be at risk from inconsistencies in potential funding and other threats. Habitats would persist, but the refuge may not be able to support designated land use to be the most effective for and greatest value to identified ROC. Overall, the No Action Alternative would not improve the Service’s ability to meet its legally mandated mission to protect other trust resources and preserve and enhance wildlife habitat. Alternative B – Proposed Alternative – Implementation of the HMP As described above, the Proposed Action is to implement the HMP and associated strategies. These strategies are aimed at increasing the dependability of the refuge as a sanctuary for target resident and migratory wildlife and aquatic species; supporting the recovery, stabilization, or growth of target populations; and promoting the resiliency and adaptability of required habitats in the face of climate change and other ecosystem threats. Proposed management would link fragmented habitats, such as forest blocks, which improves the integrity of vegetation communities. Early successional habitats will be managed more deliberately, to improve vegetation community diversity and quality and reduce the presence of invasive species. Wetland vegetation communities would continue to be protected, and where feasible, expanded or restored. Potential minor adverse impacts may occur to some species as certain habitats are transitioned across the refuge. Specifically, populations of pollinators and other early successional uplands-obligate species may decline as the gradual transition of 223 acres of such habitat to forested wetland occurs. However, adverse impacts may be offset to some degree by the increase in field habitat value and quality through proposed management actions to increase diversity and extend available bloom in remaining locations. Likewise, the transition of 48 acres of upland forest to forested wetland is likely to benefit both upland and wetland forest-dwelling species as larger blocks of contiguous, mature forest ecosystem are established. This Proposed Alternative helps meet the purpose and needs of the Service as described above because the strategic, adaptive approach to land management outlined in the HMP and the prioritization of habitats would streamline available resources to maximize benefits of management efforts. This will result in improved habitat for priority resources of concern, including migratory birds and resident wildlife. List of Preparers: U.S. Fish and Wildlife Service  Susan Guiteras – Supervisory Wildlife Biologist  Al Rizzo – Project Leader  Oscar Reed – Refuge Manager  Dan Stotts – Refuge Biologist  Bart Wilson – Project Manager  Nancy McGarigal – Natural Resource Planner (retired)  Ava Smith – Assistant Refuge Planner  Meghan Powell – Natural Resource Planner

Cardno  Dan Salas – Senior Project Ecologist/Team Lead  Benjamin Mannies – Senior Project Scientist

Appendix A. Environmental Assessment 17 August 2020 Habitat Management Plan for Bombay Hook National Wildlife Refuge

 Michael Smith – Geospatial Technician  Amy Paulson – Environmental Planner State Coordination: During early scoping and development of habitat management alternatives, refuge and Regional Planning Staff met with various representatives of state agencies, including Delaware Department of Natural Resources and Environmental Control (DNREC) and Delaware Department of Agriculture. These meetings occurred in December 2011, November 2017, and November 2018, and provided an opportunity for State input to general proposed management objectives and strategies. Public Outreach: During early development of habitat management alternatives, refuge and Regional Planning Staff provided opportunities for public input at scoping meetings in August 2011 and an open house in November 2017. Public notifications of the EA and HMP will be made available to the public through the refuge website and social media notices, and a hardcopy will be available or review at the refuge visitor center. There will be a 30-day public comment period. References: Delaware Division of Natural Resources and Environmental Control (DNREC), Division of Fish and Wildlife (DFW). 2015. The Delaware Wildlife Action Plan, 2015-2025. Accessed on 21 Aug 2018 at: http://www.dnrec.delaware.gov/fw/dwap/Pages/WAP-Progress.aspx. Holdahl, S.R. and N.L. Mossison. 1975. Regional Investigations of Vertical Crustal Movements in the U.S., Using Precise Relevelings and MareoGraph Data. Tectonophysics (23): pp. 373-390. Runkle, J., K. Kunkel, D. Easterling, R. Frankson, S. Champion, B. Stewart, W. Sweet, D. Leathers, and A.T. DeGaetano, 2017: Delaware State Climate Summary. NOAA Technical Report NESDIS 149-DE, 4 pp Springate, M.E., J.O. Walker, and D. Tvaryanas. 2011. Archaeological Overview and Assessment Study, Bombay Hook National Wildlife Refuge, Duck Creek and Little Creek Hundreds, Kent County, DE (Contract No. 501816D013, FWS/REGION 5/BA/CGS) (Task Order No. 50181-AY060). On file, USFWS Region 5, Hadley, MA. U.S. Fish & Wildlife Service (USFWS). 1975. Final Environmental Impact Statement: Proposed Bombay Hook Wilderness Area, Delaware. U.S. Department of the Interior, U.S. Fish & Wildlife Service, Washington D.C. Accessed September 2019 at: https://ecos.fws.gov/ServCat/DownloadFile/33367.

Appendix A. Environmental Assessment 18 August 2020 Habitat Management Plan for Bombay Hook National Wildlife Refuge

APPENDIX B. COMPREHENSIVE RESOURCES OF CONCERN (ROC) LIST

merica's Birds Birds merica's - Risk Species Species ic Conservation Priority Priority Conservation ic (RSGCN) State T & E FederalE T & Watchlist (2016) Watchlist Delaware SWAP SWAP Delaware BCR 3 Priority Species Priority BCR 3 XercesList Society Red of Management Concern of Management USFWS At NEPARC Species of Concern of Species NEPARC of Greatest Conservation Need Need Conservation of Greatest State of North A North Atlantic LCC Rare Plants Rare LCC North Atlantic NALCC Representative Species Representative NALCC NA Waterfowl Management Plan Management Waterfowl NA North Atlantic LCC Regional Species Species Regional LCC North Atlantic Delaware Wildlife Action Plan Species Species Plan Action Wildlife Delaware Fish and Aquat Common Name (2015)* Need Conservation of Greatest Birds Program Bird Migratory USFWS BIRDS Acadian Flycatcher Tier 3 X X X American Avocet Tier 2 X X X X American Bittern Tier 1 X X X X X American Black Duck Tier 1 X X X X X American Golden- plover Tier 3 X X X X American Kestrel Tier 1 X X X X American Oystercatcher Tier 1 X X X X X X American Redstart Tier 2 X X X American Tree Sparrow Tier 2 X X X American Widgeon Tier 2 X X X X American Woodcock Tier 2 X X X X X American/Black Scoter Tier 2 X Arctic Tern Tier 3 X X X Atlantic Brant Tier 2 X X X X Audubon's Shearwater Tier 3 X X X X Bald Eagle Tier 3 X X X X Baltimore Oriole Tier 3 X X X X Band-rumped Storm- Petrel Tier 1 X X X X X Bank Swallow Tier 2 X X X X Barn Owl Tier 2 X X X Bay-breasted Warbler Tier 3 X X X X Bicknell's Thrush Tier 1 X X X X X X Black Rail Tier 1 X X X X X X X

Appendix B. ROC List 1 August 2020 Habitat Management Plan for Bombay Hook National Wildlife Refuge

merica's Birds Birds merica's - Risk Species Species ic Conservation Priority Priority Conservation ic (RSGCN) State T & E FederalE T & Watchlist (2016) Watchlist Delaware SWAP SWAP Delaware BCR 3 Priority Species Priority BCR 3 XercesList Society Red of Management Concern of Management USFWS At NEPARC Species of Concern of Species NEPARC of Greatest Conservation Need Need Conservation of Greatest State of North A North Atlantic LCC Rare Plants Rare LCC North Atlantic NALCC Representative Species Representative NALCC NA Waterfowl Management Plan Management Waterfowl NA North Atlantic LCC Regional Species Species Regional LCC North Atlantic Delaware Wildlife Action Plan Species Species Plan Action Wildlife Delaware Fish and Aquat Common Name (2015)* Need Conservation of Greatest Birds Program Bird Migratory USFWS Black Skimmer Tier 1 X X X X X X Black Tern Tier 2 X X X Black-and-white Warbler Tier 3 X X X X X Black-bellied Plover Tier 2 X X X X Black-billed Cuckoo Tier 2 X X X Blackburnian Warbler Tier 3 X X X X X Black-crowned Night-Heron Tier 1 X X X X X Black-necked Stilt Tier 1 X Black-throated Blue Warbler Tier 3 X X X Black-throated Green Warbler Tier 3 X X X Blue-winged Teal Tier 2 X X X Blue-winged Warbler Tier 2 X X X X Bobolink Tier 2 X X X X Bridled Tern Tier 3 X X X X Broad-winged Hawk Tier 1 X X X X X Brown Creeper Tier 2 X X X Brown Pelican Tier 3 X X X Brown Thrasher Tier 3 X X X X X Brown-headed Nuthatch Tier 2 X X X X X Buff-breasted Sandpiper Tier 2 X X X X Bufflehead Tier 3 X X X X X Canada Goose Tier 1 X X X X Canada Warbler Tier 3 X X X X Canvasback Tier 3 X X X X X Cape May Warbler Tier 3 X X X Cattle Egret Tier 1 X X X Cerulean Warbler Tier 1 X X X X X X

Appendix B. ROC List 2 August 2020 Habitat Management Plan for Bombay Hook National Wildlife Refuge

merica's Birds Birds merica's - Risk Species Species ic Conservation Priority Priority Conservation ic (RSGCN) State T & E FederalE T & Watchlist (2016) Watchlist Delaware SWAP SWAP Delaware BCR 3 Priority Species Priority BCR 3 XercesList Society Red of Management Concern of Management USFWS At NEPARC Species of Concern of Species NEPARC of Greatest Conservation Need Need Conservation of Greatest State of North A North Atlantic LCC Rare Plants Rare LCC North Atlantic NALCC Representative Species Representative NALCC NA Waterfowl Management Plan Management Waterfowl NA North Atlantic LCC Regional Species Species Regional LCC North Atlantic Delaware Wildlife Action Plan Species Species Plan Action Wildlife Delaware Fish and Aquat Common Name (2015)* Need Conservation of Greatest Birds Program Bird Migratory USFWS Chestnut-sided Warbler DN X X X X Chimney Swift Tier 2 X X X X Chuck-will's-widow Tier 2 X Clapper Rail Tier 1 X X X X X Cliff Swallow Tier 2 X X X Coastal Plain Swamp Sparrow Tier 1 X X Common Eider Tier 3 X X X Common Gallinule N/A X Common Goldeneye Tier 3 X X X X Common Loon Tier 3 X X X X Common Nighthawk Tier 2 X X X X Common Tern Tier 1 X X X X X X Dickcissel Tier 2 X X X Double-crested Comorant Tier 2 X X X Dunlin Tier 1 X X X Eastern Kingbird Tier 3 X X X X Eastern Meadowlark Tier 3 X X X X Eastern Towhee Tier 3 X X X X X Eastern Whip-poor- will Tier 2 X Field Sparrow Tier 3 X X X X Forster's Tern Tier 1 X X X X X Fox Sparrow Tier 3 X X X Glossy Ibis Tier 1 X X X X Golden Eagle Tier 2 X X X X Golden-winged Warbler Tier 2 X X X X X X Grasshopper Sparrow Tier 1 X X X X X Great Black-backed Gull Tier 2 X X X Great Blue Heron Tier 3 X X X

Appendix B. ROC List 3 August 2020 Habitat Management Plan for Bombay Hook National Wildlife Refuge

merica's Birds Birds merica's - Risk Species Species ic Conservation Priority Priority Conservation ic (RSGCN) State T & E FederalE T & Watchlist (2016) Watchlist Delaware SWAP SWAP Delaware BCR 3 Priority Species Priority BCR 3 XercesList Society Red of Management Concern of Management USFWS At NEPARC Species of Concern of Species NEPARC of Greatest Conservation Need Need Conservation of Greatest State of North A North Atlantic LCC Rare Plants Rare LCC North Atlantic NALCC Representative Species Representative NALCC NA Waterfowl Management Plan Management Waterfowl NA North Atlantic LCC Regional Species Species Regional LCC North Atlantic Delaware Wildlife Action Plan Species Species Plan Action Wildlife Delaware Fish and Aquat Common Name (2015)* Need Conservation of Greatest Birds Program Bird Migratory USFWS Great Cormorant Tier 3 X X X Great Crested Flycatcher Tier 3 X X X X Great Egret Tier 2 X X X Great Shearwater Tier 3 X X X X Greater Scaup Tier 3 X X X X Greater Yellowlegs Tier 1 X X X X Gull-billed Tern Tier 2 X X X X Henslow's Sparrow Tier 1 X X X X X Herring Gull Tier 2 X X Hooded Merganser Tier 2 X X X X Hooded Warbler Tier 1 X X X X Horned Grebe Tier 3 X X X X Horned Lark Tier 2 X X X Hudsonian Godwit Tier 2 X X X X Kentucky Warbler Tier 3 X X X X King Rail Tier 1 X X X X X Laughing Gull Tier 2 X X X Least Bittern Tier 2 X X X X X Least Flycatcher DN X X X Least Tern Tier 1 X X X X Lesser Scaup Tier 3 X X X X Lesser Yellowlegs Tier 1 X X X X Little Blue Heron Tier 2 X X X X Loggerhead Shrike DN X X X X Long-eared Owl Tier 2 X X X Long-tailed Duck Tier 1 X X X X X Long-tailed Jaeger Tier 3 X X X Louisiana Waterthrush Tier 3 X X X X Mallard Tier 2 X X X X Marbled Godwit Tier 2 X X X X

Appendix B. ROC List 4 August 2020 Habitat Management Plan for Bombay Hook National Wildlife Refuge

merica's Birds Birds merica's - Risk Species Species ic Conservation Priority Priority Conservation ic (RSGCN) State T & E FederalE T & Watchlist (2016) Watchlist Delaware SWAP SWAP Delaware BCR 3 Priority Species Priority BCR 3 XercesList Society Red of Management Concern of Management USFWS At NEPARC Species of Concern of Species NEPARC of Greatest Conservation Need Need Conservation of Greatest State of North A North Atlantic LCC Rare Plants Rare LCC North Atlantic NALCC Representative Species Representative NALCC NA Waterfowl Management Plan Management Waterfowl NA North Atlantic LCC Regional Species Species Regional LCC North Atlantic Delaware Wildlife Action Plan Species Species Plan Action Wildlife Delaware Fish and Aquat Common Name (2015)* Need Conservation of Greatest Birds Program Bird Migratory USFWS Marsh Wren Tier 2 X X X X Merlin Tier 3 X X X Nelson's Sparrow Tier 1 X X X X X Northern Bobwhite Tier 2 X X X Northern Flicker Tier 3 X X X X Northern Gannet Tier 3 X X X X Northern Goshawk Tier 3 X X X Northern Harrier Tier 1 X X X X Northern Parula Tier 2 X X X Northern Pintail Tier 2 X X X X X Northern Saw-whet Owl Tier 3 X X X Olive-sided Flycatcher Tier 2 X X X Pectoral Sandpiper Tier 3 X X X Peregrine Falcon Tier 1 X X Pied-billed Grebe Tier 1 X X X X Pine Siskin Tier 2 X X X Piping Plover Tier 1 X X X X X X X X X X Prairie Warbler Tier 3 X X X X Prothonotary Warbler Tier 3 X X X X X Purple Finch Tier 3 X X X Purple Sandpiper Tier 2 X X X X X X Red Knot Tier 1 X X X X X X Red-breasted Nuthatch Tier 2 X X X Redhead Tier 3 X X X Red-headed Woodpecker Tier 2 X X X X Red-necked Phalarope Tier 3 X X X X Red-shouldered Hawk Tier 3 X X X X Red-throated Loon Tier 2 X X X X

Appendix B. ROC List 5 August 2020 Habitat Management Plan for Bombay Hook National Wildlife Refuge

merica's Birds Birds merica's - Risk Species Species ic Conservation Priority Priority Conservation ic (RSGCN) State T & E FederalE T & Watchlist (2016) Watchlist Delaware SWAP SWAP Delaware BCR 3 Priority Species Priority BCR 3 XercesList Society Red of Management Concern of Management USFWS At NEPARC Species of Concern of Species NEPARC of Greatest Conservation Need Need Conservation of Greatest State of North A North Atlantic LCC Rare Plants Rare LCC North Atlantic NALCC Representative Species Representative NALCC NA Waterfowl Management Plan Management Waterfowl NA North Atlantic LCC Regional Species Species Regional LCC North Atlantic Delaware Wildlife Action Plan Species Species Plan Action Wildlife Delaware Fish and Aquat Common Name (2015)* Need Conservation of Greatest Birds Program Bird Migratory USFWS Roseate Tern Tier 1 X X X X Rose-breasted Grosbeak Tier 2 X X X Rough-legged Hawk Tier 3 X X X Ruddy Duck Tier 2 X X X X Ruddy Turnstone Tier 1 X X X X Rusty Blackbird Tier 1 X X X X Saltmarsh Sparrow Tier 1 X X X X X X X Sanderling Tier 1 X X X X X Sandwich Tern Tier 2 X X X Savannah Sparrow Tier 2 X X X X Scarlet Tanager Tier 2 X X X X Seaside Sparrow Tier 1 X X X X Sedge Wren Tier 1 X X X X X Semipalmated Sandpiper Tier 1 X X X X X Sharp-shinned Hawk Tier 2 X X X Short-billed Dowitcher Tier 1 X X X X Short-eared Owl Tier 1 X X X X X Snow Bunting Tier 3 X X X Snowy Egret Tier 1 X X X X X Solitary Sandpiper Tier 3 X X X X Sooty Shearwater Tier 2 X X X Sora Tier 2 X X X X Spotted Sandpiper Tier 2 X X X X Summer Tanager Tier 3 X X X Surf Scoter Tier 2 X X X X Swainson's Warbler Tier 1 X X X X X Thick-billed murre Tier 3 X X X Tricolored Heron Tier 1 X X X X Tundra Swan Tier 2 X X X X

Appendix B. ROC List 6 August 2020 Habitat Management Plan for Bombay Hook National Wildlife Refuge

merica's Birds Birds merica's - Risk Species Species ic Conservation Priority Priority Conservation ic (RSGCN) State T & E FederalE T & Watchlist (2016) Watchlist Delaware SWAP SWAP Delaware BCR 3 Priority Species Priority BCR 3 XercesList Society Red of Management Concern of Management USFWS At NEPARC Species of Concern of Species NEPARC of Greatest Conservation Need Need Conservation of Greatest State of North A North Atlantic LCC Rare Plants Rare LCC North Atlantic NALCC Representative Species Representative NALCC NA Waterfowl Management Plan Management Waterfowl NA North Atlantic LCC Regional Species Species Regional LCC North Atlantic Delaware Wildlife Action Plan Species Species Plan Action Wildlife Delaware Fish and Aquat Common Name (2015)* Need Conservation of Greatest Birds Program Bird Migratory USFWS Upland Sandpiper Tier 1 X X X X X X Veery Tier 2 X X X Vesper Sparrow Tier 3 X X Virginia Rail Tier 2 X X X X Warbling Vireo Tier 2 X X X X Whimbrel Tier 2 X X X X X White-faced Storm- Petrel Tier 3 X X White-rumped Sandpiper Tier 2 X X X X White-winged Scoter Tier 3 X X X X X Willet Tier 1 X X X X X Willow Flycatcher Tier 2 X X X X X Wilson's Phalarope Tier 3 X X X X Wilson's Snipe Tier 3 X X X Wood Thrush Tier 2 X X X X X X Worm-eating Warbler Tier 3 X X X X X Yellow-breasted Chat Tier 3 X X X Yellow-crowned Night-Heron Tier 1 X X X X X Yellow-throated Vireo Tier 3 X X X X Yellow-throated Warbler Tier 2 X X X AMPHIBIANS Atlantic Coast Leopard Frog Tier 1 X Barking Treefrog Tier 1 X X X Carpenter Frog Tier 1 X X Cope's Gray Treefrog Tier 2 X X Eastern Mud Salamander Tier 1 X X X X Eastern Spadefoot Toad Tier 2 X X

Appendix B. ROC List 7 August 2020 Habitat Management Plan for Bombay Hook National Wildlife Refuge

merica's Birds Birds merica's - Risk Species Species ic Conservation Priority Priority Conservation ic (RSGCN) State T & E FederalE T & Watchlist (2016) Watchlist Delaware SWAP SWAP Delaware BCR 3 Priority Species Priority BCR 3 XercesList Society Red of Management Concern of Management USFWS At NEPARC Species of Concern of Species NEPARC of Greatest Conservation Need Need Conservation of Greatest State of North A North Atlantic LCC Rare Plants Rare LCC North Atlantic NALCC Representative Species Representative NALCC NA Waterfowl Management Plan Management Waterfowl NA North Atlantic LCC Regional Species Species Regional LCC North Atlantic Delaware Wildlife Action Plan Species Species Plan Action Wildlife Delaware Fish and Aquat Common Name (2015)* Need Conservation of Greatest Birds Program Bird Migratory USFWS Eastern/Northern Cricket Frog Tier 2 X Eastern/Tiger Salamander Tier 1 X X X Four-toed Salamander Tier 2 X X Fowler's Toad Tier 3 X X Longtail Salamander Tier 2 X Marbled Salamander Tier 3 X X X New Jersey Chorus Frog Tier 2 X X Northern Dusky Salamander Tier 3 X X Northern Red Salamander Tier 2 X Northern Two-lined Salamander Tier 3 X X Red-spotted Newt Tier 3 X X Spotted Salamander Tier 2 X X X Wood Frog Tier 3 X X X X REPTILES Atlantic Green Sea Turtle Tier 1 X X X X X X X Atlantic Hawksbill Sea Turtle Tier 1 X X X X X Atlantic Leatherback Sea Turtle Tier 1 X X X X X X X Atlantic Loggerhead Sea Turtle Tier 1 X X X X X X X X Bog Turtle Tier 1 X X X X X X Broad-headed Skink DN X X Brownsnake Tier 3 X E. Redbelly Turtle/N. Red-bellied Cooter Tier 2 X X X X Eastern Box Turtle Tier 1 X X X Eastern Hog-nosed Snake Tier 3 X X X

Appendix B. ROC List 8 August 2020 Habitat Management Plan for Bombay Hook National Wildlife Refuge

merica's Birds Birds merica's - Risk Species Species ic Conservation Priority Priority Conservation ic (RSGCN) State T & E FederalE T & Watchlist (2016) Watchlist Delaware SWAP SWAP Delaware BCR 3 Priority Species Priority BCR 3 XercesList Society Red of Management Concern of Management USFWS At NEPARC Species of Concern of Species NEPARC of Greatest Conservation Need Need Conservation of Greatest State of North A North Atlantic LCC Rare Plants Rare LCC North Atlantic NALCC Representative Species Representative NALCC NA Waterfowl Management Plan Management Waterfowl NA North Atlantic LCC Regional Species Species Regional LCC North Atlantic Delaware Wildlife Action Plan Species Species Plan Action Wildlife Delaware Fish and Aquat Common Name (2015)* Need Conservation of Greatest Birds Program Bird Migratory USFWS Eastern Kingsnake Tier 2 X Eastern Milksnake Tier 2 X X Eastern Ribbonsnake Tier 2 X X Eastern/Northern Scarlet Snake Tier 1 X X Ground Skink Tier 2 X X Kemp's Atlantic Ridley Sea Turtle Tier 1 X X X X X X X Northern Black Racer N/A X X X Northern Copperhead Snake Tier 2 X Northern Diamond- backed Terrapin Tier 2 X X X Northern Ring- necked Snake Tier 3 X X Queen Snake Tier 2 X X Red Cornsnake Tier 1 X X Redbellied Snake Tier 2 X Redbelly Watersnake Tier 1 X X Rough Greensnake Tier 2 X X Smooth/Eastern Earthsnake Tier 2 X Spotted Turtle Tier 1 X X X X X MAMMALS American Mink Tier 2 X Big Brown Bat Tier 3 X Blue Whale Tier 2 X X X X X Bobcat X Delmarva Fox Squirrel Tier 1 X X X X Eastern Red Bat Tier 3 X X X Eastern Small-footed Bat Tier 1 X X Evening Bat Tier 2 X Fin Whale Tier 3 X X X X X

Appendix B. ROC List 9 August 2020 Habitat Management Plan for Bombay Hook National Wildlife Refuge

merica's Birds Birds merica's - Risk Species Species ic Conservation Priority Priority Conservation ic (RSGCN) State T & E FederalE T & Watchlist (2016) Watchlist Delaware SWAP SWAP Delaware BCR 3 Priority Species Priority BCR 3 XercesList Society Red of Management Concern of Management USFWS At NEPARC Species of Concern of Species NEPARC of Greatest Conservation Need Need Conservation of Greatest State of North A North Atlantic LCC Rare Plants Rare LCC North Atlantic NALCC Representative Species Representative NALCC NA Waterfowl Management Plan Management Waterfowl NA North Atlantic LCC Regional Species Species Regional LCC North Atlantic Delaware Wildlife Action Plan Species Species Plan Action Wildlife Delaware Fish and Aquat Common Name (2015)* Need Conservation of Greatest Birds Program Bird Migratory USFWS Harbor Porpoise Tier 3 X Hoary Bat DN X X Humpback Whale Tier 1 X X X X Little Brown Bat Tier 1 X X X X X Long-tailed Weasel Tier 3 X Maryland Shrew DN X North American Least Shrew Tier 3 X X North Atlantic Right Whale Tier 1 X X X X X X Northern Long-eared Bat Tier 2 X X X X X X Sei Whale Tier 1 X X X X X Silver-haired Bat DN X X Sperm Whale Tier 1 X X X X X Star-nosed Mole Tier 3 X Tri-colored Bat Tier 2 X X X X FISH Alewife Tier 1 X X X American Brook Lamprey Tier 2 X X American Eel Tier 1 X X American Goosefish Tier 3 X American Sand Lance Tier 2 X American Shad Tier 2 X X Atlantic Angel Shark DN X Atlantic Bluefin Tuna Tier 1 X X Atlantic Croaker Tier 3 X Atlantic Herring Tier 3 X Atlantic Mackerel Tier 3 X Atlantic Menhaden Tier 2 X Atlantic Sharpnose Shark Tier 3 X

Appendix B. ROC List 10 August 2020 Habitat Management Plan for Bombay Hook National Wildlife Refuge

merica's Birds Birds merica's - Risk Species Species ic Conservation Priority Priority Conservation ic (RSGCN) State T & E FederalE T & Watchlist (2016) Watchlist Delaware SWAP SWAP Delaware BCR 3 Priority Species Priority BCR 3 XercesList Society Red of Management Concern of Management USFWS At NEPARC Species of Concern of Species NEPARC of Greatest Conservation Need Need Conservation of Greatest State of North A North Atlantic LCC Rare Plants Rare LCC North Atlantic NALCC Representative Species Representative NALCC NA Waterfowl Management Plan Management Waterfowl NA North Atlantic LCC Regional Species Species Regional LCC North Atlantic Delaware Wildlife Action Plan Species Species Plan Action Wildlife Delaware Fish and Aquat Common Name (2015)* Need Conservation of Greatest Birds Program Bird Migratory USFWS Atlantic Silverside Tier 3 X Atlantic Sturgeon Tier 1 X X X Atlantic Tomcod Tier 3 X Banded Sunfish Tier 2 X X Basking Shark Tier 1 X Bigeye Thresher Shark Tier 1 X X Black Drum Tier 3 X Black Sea Bass Tier 2 X X Blackbanded Sunfish Tier 1 X X X Blacktip Shark Tier 2 X Blue Ridge Sculpin Tier 1 X X Blue Shark Tier 2 X Blueback Herring Tier 1 X X Bluefish Tier 3 X X Bluntnose Sixgill Shark Tier 2 X Bonnethead Shark Tier 3 X Bowfin Tier 3 X Bridle Shiner Tier 1 X X X Bull Shark Tier 2 X Butterfish Tier 3 X Comely Shiner Tier 2 X Cunner Tier 3 X Cutlip Minnow Tier 3 X Dusky Shark Tier 2 X X Eastern Mud Minnow Tier 3 X Eastern Silvery Minnow Tier 3 X Fallfish Tier 3 X Finetooth Shark Tier 3 X Fourspine Stickleback Tier 2 X

Appendix B. ROC List 11 August 2020 Habitat Management Plan for Bombay Hook National Wildlife Refuge

merica's Birds Birds merica's - Risk Species Species ic Conservation Priority Priority Conservation ic (RSGCN) State T & E FederalE T & Watchlist (2016) Watchlist Delaware SWAP SWAP Delaware BCR 3 Priority Species Priority BCR 3 XercesList Society Red of Management Concern of Management USFWS At NEPARC Species of Concern of Species NEPARC of Greatest Conservation Need Need Conservation of Greatest State of North A North Atlantic LCC Rare Plants Rare LCC North Atlantic NALCC Representative Species Representative NALCC NA Waterfowl Management Plan Management Waterfowl NA North Atlantic LCC Regional Species Species Regional LCC North Atlantic Delaware Wildlife Action Plan Species Species Plan Action Wildlife Delaware Fish and Aquat Common Name (2015)* Need Conservation of Greatest Birds Program Bird Migratory USFWS Fourspot Flounder Tier 3 X Glassy Darter Tier 1 X X X Great Hammerhead Tier 1 X Hickory Shad Tier 2 X Ironcolor Shiner Tier 1 X X Least Brook Lamprey Tier 2 X Lemon Shark Tier 2 X Little Skate Tier 2 X Longfin Mako Shark Tier 1 X X Longhorn Sculpin Tier 3 X Mottled Sculpin Tier 2 X Mud Sunfish Tier 2 X Mummichog Tier 3 X Night Shark Tier 1 X X Northern Puffer Tier 3 X Northern Searobin Tier 3 X Nurse Shark DN X Ocean Pout Tier 3 X Oceanic Whitetip Shark Tier 1 X Oyster Toadfish Tier 2 X Porbeagle Shark Tier 1 X X Red Drum Tier 3 X Red Hake Tier 3 X Redbreast Sunfish Tier 3 X Rosette Skate Tier 3 X Roughtail Stingray Tier 3 X Sand Tiger Shark Tier 1 X Sandbar Shark Tier 1 X Satinfin Shiner Tier 3 X Scalloped Hammerhead Shark Tier 1 X X X X

Appendix B. ROC List 12 August 2020 Habitat Management Plan for Bombay Hook National Wildlife Refuge

merica's Birds Birds merica's - Risk Species Species ic Conservation Priority Priority Conservation ic (RSGCN) State T & E FederalE T & Watchlist (2016) Watchlist Delaware SWAP SWAP Delaware BCR 3 Priority Species Priority BCR 3 XercesList Society Red of Management Concern of Management USFWS At NEPARC Species of Concern of Species NEPARC of Greatest Conservation Need Need Conservation of Greatest State of North A North Atlantic LCC Rare Plants Rare LCC North Atlantic NALCC Representative Species Representative NALCC NA Waterfowl Management Plan Management Waterfowl NA North Atlantic LCC Regional Species Species Regional LCC North Atlantic Delaware Wildlife Action Plan Species Species Plan Action Wildlife Delaware Fish and Aquat Common Name (2015)* Need Conservation of Greatest Birds Program Bird Migratory USFWS Scup Tier 1 X Sea Raven Tier 3 X Sharpnose Sevengill Shark Tier 2 X Shield Darter Tier 2 X Shortfin Mako Shark Tier 1 X X Shorthead Redhorse Tier 2 X Shortnose Sturgeon Tier 1 X X X X X X X Silky Shark Tier 2 X Silver Hake Tier 3 X Smooth Dogfish Tier 2 X Smooth Hammerhead Shark Tier 1 X X Spanish Mackerel Tier 3 X Spinner Shark Tier 2 X Spiny Dogfish Tier 1 X X Spot Tier 3 X Spotfin Killfish Tier 2 X Spotted Seatrout Tier 3 X Spotted/Margined Madtom Tier 2 X Striped Bass Tier 2 X Striped Killfish Tier 3 X Striped Searobin Tier 3 X Summer Flounder Tier 3 X X Swallowtail Shiner Tier 3 X Swamp Darter Tier 3 X X Tautog Tier 1 X X Thresher Shark Tier 1 X X Tiger Shark Tier 2 X Weakfish Tier 2 X X Whale Shark Tier 1 X X

Appendix B. ROC List 13 August 2020 Habitat Management Plan for Bombay Hook National Wildlife Refuge

merica's Birds Birds merica's - Risk Species Species ic Conservation Priority Priority Conservation ic (RSGCN) State T & E FederalE T & Watchlist (2016) Watchlist Delaware SWAP SWAP Delaware BCR 3 Priority Species Priority BCR 3 XercesList Society Red of Management Concern of Management USFWS At NEPARC Species of Concern of Species NEPARC of Greatest Conservation Need Need Conservation of Greatest State of North A North Atlantic LCC Rare Plants Rare LCC North Atlantic NALCC Representative Species Representative NALCC NA Waterfowl Management Plan Management Waterfowl NA North Atlantic LCC Regional Species Species Regional LCC North Atlantic Delaware Wildlife Action Plan Species Species Plan Action Wildlife Delaware Fish and Aquat Common Name (2015)* Need Conservation of Greatest Birds Program Bird Migratory USFWS White Shark Tier 1 X X Windowpane Flounder Tier 3 X Winter Flounder Tier 3 X X Winter Skate Tier 1 X X INVERTEBRATES American Lobster Tier 3 X Blue Crab Tier 2 X A Caddisfly Tier 1 X A Cellophane Bee Tier 1 X A Cuckoo Bee Tier 2 X A Dagger Moth DN X A Dytiscid Beetle Tier 1 X A Firefly Tier 1 X A Geometrid Moth Tier 2 X A Hydrophilid Beetle DN X A Mother Underwing DN X A Noctuid Moth DN X A Notodontid Moth DN X A Residua Underwing Tier 2 X A Spider Wasp Tier 1 X A Sweat Bee Tier 2 X A Walnut Sphinx DN X A Water Scavenger Beetle DN X Alabama Underwing Tier 1 X Amber-winged Spreadwing Tier 1 X American Bumble Bee Tier 1 X X American Burying Beetle Ext X X X X

Appendix B. ROC List 14 August 2020 Habitat Management Plan for Bombay Hook National Wildlife Refuge

merica's Birds Birds merica's - Risk Species Species ic Conservation Priority Priority Conservation ic (RSGCN) State T & E FederalE T & Watchlist (2016) Watchlist Delaware SWAP SWAP Delaware BCR 3 Priority Species Priority BCR 3 XercesList Society Red of Management Concern of Management USFWS At NEPARC Species of Concern of Species NEPARC of Greatest Conservation Need Need Conservation of Greatest State of North A North Atlantic LCC Rare Plants Rare LCC North Atlantic NALCC Representative Species Representative NALCC NA Waterfowl Management Plan Management Waterfowl NA North Atlantic LCC Regional Species Species Regional LCC North Atlantic Delaware Wildlife Action Plan Species Species Plan Action Wildlife Delaware Fish and Aquat Common Name (2015)* Need Conservation of Greatest Birds Program Bird Migratory USFWS American Snout Butterfly Tier 2 X An Underwing Moth Tier 2 X Angel Winged Emerald Moth Tier 2 X Aphrodite Fritillary DN X Appalachian Azure Tier 1 X Aralia Shoot Borer Moth Tier 1 X X X Arctiid A Moth Tier 2 X Arrow Clubtail Tier 2 X Ash Borer Moth DN X Ash Sphinx DN X Ashy Clubtail Tier 3 X Attenuated Bluet Tier 2 X Aurora Damsel Tier 2 X Azure Bluet Tier 3 X Baltimore Checkerspot Tier 1 X X Banded Pennant DN X Band-winged Meadowhawk Tier 2 X Banner Clubtail Tier 1 X X Bar-winged Skimmer Tier 2 X Bent Forestfly Tier 1 X Bethany Beach Firefly Tier 1 X X Big Bluet Tier 2 X Black Alder/Pawpaw Sphinx DN X Black and Gold Bumble Bee Tier 2 X Black Dash Tier 1 X X Blacked-etched Prominent DN X

Appendix B. ROC List 15 August 2020 Habitat Management Plan for Bombay Hook National Wildlife Refuge

merica's Birds Birds merica's - Risk Species Species ic Conservation Priority Priority Conservation ic (RSGCN) State T & E FederalE T & Watchlist (2016) Watchlist Delaware SWAP SWAP Delaware BCR 3 Priority Species Priority BCR 3 XercesList Society Red of Management Concern of Management USFWS At NEPARC Species of Concern of Species NEPARC of Greatest Conservation Need Need Conservation of Greatest State of North A North Atlantic LCC Rare Plants Rare LCC North Atlantic NALCC Representative Species Representative NALCC NA Waterfowl Management Plan Management Waterfowl NA North Atlantic LCC Regional Species Species Regional LCC North Atlantic Delaware Wildlife Action Plan Species Species Plan Action Wildlife Delaware Fish and Aquat Common Name (2015)* Need Conservation of Greatest Birds Program Bird Migratory USFWS Black-Shouldered Spineyleg Tier 2 X Black-tipped Darner Tier 1 X X Blackwater Bluet Tier 2 X Blue-ringed Dancer DN X Bracken Borer Moth DN X Brick-red Borer Moth Tier 1 X Bronze Copper Tier 2 X Brown Elfin DN X Brown Spiketail Tier 1 X X Buffalo Moth DN X Burgundy Bluet Tier 1 X X Calico Pennant Tier 3 X Canadian Owlet Tier 2 X Chain Fern Borer Moth Tier 2 X Checkered White DN X Chermock's Mulberry Wing Tier 1 X X X Clamp-tipped Emerald Tier 3 X Clouded Underwing Tier 2 X Cobweb Skipper Tier 1 X Colona Moth DN X Comet Darner Tier 3 X Common Sanddragon Tier 2 X Coneflower Borer Moth Tier 1 X Cow Path Tiger Beetle DN X Dark Stoneroot Borer Moth Tier 1 X X X Dejected Underwing Tier 1 X Delaware Skipper Tier 2 X

Appendix B. ROC List 16 August 2020 Habitat Management Plan for Bombay Hook National Wildlife Refuge

merica's Birds Birds merica's - Risk Species Species ic Conservation Priority Priority Conservation ic (RSGCN) State T & E FederalE T & Watchlist (2016) Watchlist Delaware SWAP SWAP Delaware BCR 3 Priority Species Priority BCR 3 XercesList Society Red of Management Concern of Management USFWS At NEPARC Species of Concern of Species NEPARC of Greatest Conservation Need Need Conservation of Greatest State of North A North Atlantic LCC Rare Plants Rare LCC North Atlantic NALCC Representative Species Representative NALCC NA Waterfowl Management Plan Management Waterfowl NA North Atlantic LCC Regional Species Species Regional LCC North Atlantic Delaware Wildlife Action Plan Species Species Plan Action Wildlife Delaware Fish and Aquat Common Name (2015)* Need Conservation of Greatest Birds Program Bird Migratory USFWS Delta-spotted Spiketail Tier 2 X Dion/Sedge Skipper Tier 1 X Dot-tailed Whiteface DN X Double-ringed Pennant Tier 2 X Double-striped Bluet Tier 2 X Dreamy Duskywing DN X Duckweed Firetail Tier 2 X Dusky Dancer Tier 2 X Dusted Skipper Tier 1 X Eastern Beach Tiger Beetle Tier 1 X X Eastern Buckmoth DN X Eastern Cactus- boring Moth DN X Eastern Least Clubtail Tier 2 X Eastern Red Damsel Tier 3 X Elegant Spreadwing Tier 2 X Elfin Skimmer Tier 1 X X X Eupatorium Borer Moth DN X Exiled Dagger Moth Tier 2 X Eyed Brown DN X Fawn Darner Tier 3 X Festive Tiger Beetle Tier 2 X Fine-lined Emerald Tier 2 X Four-lined Chocolate Moth DN X Four-spotted Pennant Tier 2 X Franck's Sphinx DN X Frosted Elfin Tier 1 X X X X X Galium Sphinx DN X

Appendix B. ROC List 17 August 2020 Habitat Management Plan for Bombay Hook National Wildlife Refuge

merica's Birds Birds merica's - Risk Species Species ic Conservation Priority Priority Conservation ic (RSGCN) State T & E FederalE T & Watchlist (2016) Watchlist Delaware SWAP SWAP Delaware BCR 3 Priority Species Priority BCR 3 XercesList Society Red of Management Concern of Management USFWS At NEPARC Species of Concern of Species NEPARC of Greatest Conservation Need Need Conservation of Greatest State of North A North Atlantic LCC Rare Plants Rare LCC North Atlantic NALCC Representative Species Representative NALCC NA Waterfowl Management Plan Management Waterfowl NA North Atlantic LCC Regional Species Species Regional LCC North Atlantic Delaware Wildlife Action Plan Species Species Plan Action Wildlife Delaware Fish and Aquat Common Name (2015)* Need Conservation of Greatest Birds Program Bird Migratory USFWS Giant Stag Beetle DN X Golden-banded Skipper DN X Golden-winged Skimmer Tier 2 X Gray Comma DN X Great Ash Sphinx DN X Great Purple Hairstreak Tier 1 X Great Spreadwing Tier 2 X Green-striped Darner Tier 2 X Grote's Sallow DN X Gypsy/Ashton's Cuckoo Bumble Bee DN X X Habilis Underwing Tier 2 X Hackberry Emporer Tier 2 X Hairy-necked Tiger Beetle Tier 2 X Half-black Bumble Bee Tier 2 X Harlequin Darner Tier 2 X Harvester Tier 1 X Henry's Elfin DN X Hermit Sphinx Tier 1 X Hessel's Hairstreak Tier 1 X X X X Hobomok Skipper DN X Hop Borer Tier 1 X Hübner's Pero Moth Tier 2 X Huckelberry Sphinx DN X Hydrangea Sphinx Moth Tier 2 X Imperial Moth DN X Inconsolable Underwing DN X Indian Skipper DN X

Appendix B. ROC List 18 August 2020 Habitat Management Plan for Bombay Hook National Wildlife Refuge

merica's Birds Birds merica's - Risk Species Species ic Conservation Priority Priority Conservation ic (RSGCN) State T & E FederalE T & Watchlist (2016) Watchlist Delaware SWAP SWAP Delaware BCR 3 Priority Species Priority BCR 3 XercesList Society Red of Management Concern of Management USFWS At NEPARC Species of Concern of Species NEPARC of Greatest Conservation Need Need Conservation of Greatest State of North A North Atlantic LCC Rare Plants Rare LCC North Atlantic NALCC Representative Species Representative NALCC NA Waterfowl Management Plan Management Waterfowl NA North Atlantic LCC Regional Species Species Regional LCC North Atlantic Delaware Wildlife Action Plan Species Species Plan Action Wildlife Delaware Fish and Aquat Common Name (2015)* Need Conservation of Greatest Birds Program Bird Migratory USFWS Juniper Hairstreak Tier 2 X Kentucky Lichen Moth DN X King's Hairstreak Tier 1 X X X X Lancet Clubtail Tier 3 X Laura's Clubtail Tier 1 X X Lettered Sphinx DN X Lilypad Forktail Tier 2 X Little Blue Dragonlet Tier 2 X Little Glassywing DN X Little Underwing DN X Loosestrife Borer Moth DN X Marbled Underwing Tier 1 X X X Margined Tiger Beetle N/A X Maritime Sunflower Borer Moth Tier 1 X X Martha's Pennant DN X X Masked Parahypenodes Moth DN X May Apple Borer Moth DN X Meadow Fritillary Tier 1 X Midland Clubtail Tier 1 X X Mocha Emerald Tier 3 X Monarch Butterfly Tier 1 X X Mottled Duskywing Tier 1 X X Mournful Underwing Tier 2 X Mulberry Wing Tier 1 X X Myrina Fritillary Tier 2 X Needham's Skimmer Tier 2 X Nessus Sphinx Tier 3 X

Appendix B. ROC List 19 August 2020 Habitat Management Plan for Bombay Hook National Wildlife Refuge

merica's Birds Birds merica's - Risk Species Species ic Conservation Priority Priority Conservation ic (RSGCN) State T & E FederalE T & Watchlist (2016) Watchlist Delaware SWAP SWAP Delaware BCR 3 Priority Species Priority BCR 3 XercesList Society Red of Management Concern of Management USFWS At NEPARC Species of Concern of Species NEPARC of Greatest Conservation Need Need Conservation of Greatest State of North A North Atlantic LCC Rare Plants Rare LCC North Atlantic NALCC Representative Species Representative NALCC NA Waterfowl Management Plan Management Waterfowl NA North Atlantic LCC Regional Species Species Regional LCC North Atlantic Delaware Wildlife Action Plan Species Species Plan Action Wildlife Delaware Fish and Aquat Common Name (2015)* Need Conservation of Greatest Birds Program Bird Migratory USFWS Northern Barrens Tiger Beetle Tier 1 X X Northern Flower Moth Tier 1 X X Obscure Underwing Tier 2 X Obtuse Yellow Tier 2 X Once-Married Underwing DN X One-spotted Tiger Beetle Tier 2 X Osmunda Borer Moth Tier 1 X Painted Skimmer Tier 3 X Pale Bluet Tier 1 X X Phyllira Tiger Moth DN X Pine Barrens Tiger Beetle DN X Pink Spotted HawkMoth DN X Pipe Vine Swallow Tail Tier 2 X Pitcher Plant Borer Moth Tier 1 X X Pitcher Plant Moth Tier 1 X Praeclara Underwing Tier 2 X Rare Skipper Tier 1 X X X X Red-Bellied Tiger Beetle DN X Regal Fritillary Ext X X X X Robust Baskettail Tier 1 X Royal River Cruiser Tier 2 X Ruby Meadowhawk Tier 3 X Russet-tipped Clubtail Tier 2 X Rustic Sphinx Tier 2 X Rusty-patched Bumble Bee Tier 1 X X X X X X

Appendix B. ROC List 20 August 2020 Habitat Management Plan for Bombay Hook National Wildlife Refuge

merica's Birds Birds merica's - Risk Species Species ic Conservation Priority Priority Conservation ic (RSGCN) State T & E FederalE T & Watchlist (2016) Watchlist Delaware SWAP SWAP Delaware BCR 3 Priority Species Priority BCR 3 XercesList Society Red of Management Concern of Management USFWS At NEPARC Species of Concern of Species NEPARC of Greatest Conservation Need Need Conservation of Greatest State of North A North Atlantic LCC Rare Plants Rare LCC North Atlantic NALCC Representative Species Representative NALCC NA Waterfowl Management Plan Management Waterfowl NA North Atlantic LCC Regional Species Species Regional LCC North Atlantic Delaware Wildlife Action Plan Species Species Plan Action Wildlife Delaware Fish and Aquat Common Name (2015)* Need Conservation of Greatest Birds Program Bird Migratory USFWS Sable Clubtail Tier 1 X X X Sad Underwing Tier 2 X Scribbled Sallow Moth DN X Seaside Dragonlet Tier 2 X Sedge Sprite DN X Seepage Dancer Tier 1 X Selys' Sundragon Tier 1 X X Sensitive Fern Borer Moth Tier 3 X Seth Forest Water Scavenger Beetle Tier 1 X X Skimming Bluet Tier 3 X Sleepy Duskywing DN X Slender Bluet Tier 3 X Slender Spreadwing Tier 3 X Small Tolype Moth DN X Southern Broken- Dash Tier 2 X Southern Pine Looper Moth Tier 2 X Southern Pine Sphinx Tier 2 X Southern Plains Bumble Bee Tier 1 X Southern Pygmy Clubtail Tier 1 X Southern Spreadwing Tier 2 X Southern Sprite Tier 2 X Spangled Skimmer Tier 3 X Sparkling Jewelwing Tier 2 X Spatterdock Darner Tier 1 X X Spectral/Little White/Dune Ghost Tiger Beetle Tier 1 X X X Sphagnum Sprite Tier 2 X

Appendix B. ROC List 21 August 2020 Habitat Management Plan for Bombay Hook National Wildlife Refuge

merica's Birds Birds merica's - Risk Species Species ic Conservation Priority Priority Conservation ic (RSGCN) State T & E FederalE T & Watchlist (2016) Watchlist Delaware SWAP SWAP Delaware BCR 3 Priority Species Priority BCR 3 XercesList Society Red of Management Concern of Management USFWS At NEPARC Species of Concern of Species NEPARC of Greatest Conservation Need Need Conservation of Greatest State of North A North Atlantic LCC Rare Plants Rare LCC North Atlantic NALCC Representative Species Representative NALCC NA Waterfowl Management Plan Management Waterfowl NA North Atlantic LCC Regional Species Species Regional LCC North Atlantic Delaware Wildlife Action Plan Species Species Plan Action Wildlife Delaware Fish and Aquat Common Name (2015)* Need Conservation of Greatest Birds Program Bird Migratory USFWS Spotted Spreadwing Tier 2 X Spring-loving Psiloneuran Caddisfly Tier 1 X Springtime Darner Tier 3 X Streaked Dagger Moth DN X Stream Cruiser Tier 3 X Striped Hairstreak Tier 2 Stripe-winged Baskettail Tier 2 X Swamp Spreadwing Tier 3 X Sweetfern Underwing DN X Sweetflag Spreadwing Tier 2 X Swift River Cruiser Tier 2 X Taper-tailed Darner Tier 1 X X Tawny Emporer Tier 2 X Tearful Underwing Tier 2 X The Betrothed Underwing Tier 3 X Thin-banded Lichen Moth DN X Thin-winged Owlet Moth Tier 1 X Three Lined Flower Moth DN X Tiger Spiketail Tier 1 X X Treetop Emerald Tier 1 X X Trumpet Vine Sphinx DN X Turquoise Bluet Tier 3 X Tussock A Moth Tier 1 X Twelve-spotted Tiger Beetle DN X

Appendix B. ROC List 22 August 2020 Habitat Management Plan for Bombay Hook National Wildlife Refuge

merica's Birds Birds merica's - Risk Species Species ic Conservation Priority Priority Conservation ic (RSGCN) State T & E FederalE T & Watchlist (2016) Watchlist Delaware SWAP SWAP Delaware BCR 3 Priority Species Priority BCR 3 XercesList Society Red of Management Concern of Management USFWS At NEPARC Species of Concern of Species NEPARC of Greatest Conservation Need Need Conservation of Greatest State of North A North Atlantic LCC Rare Plants Rare LCC North Atlantic NALCC Representative Species Representative NALCC NA Waterfowl Management Plan Management Waterfowl NA North Atlantic LCC Regional Species Species Regional LCC North Atlantic Delaware Wildlife Action Plan Species Species Plan Action Wildlife Delaware Fish and Aquat Common Name (2015)* Need Conservation of Greatest Birds Program Bird Migratory USFWS Twin-spotted Spiketail Tier 3 X Umbellifer Borer Moth DN X Umber Shadowdragon Tier 2 X Unicorn Clubtail Tier 3 X Variable Cuckoo Bumble Bee DN X X Vesper Bluet Tier 2 X Virginia Big-headed Tiger Beetle DN X Washed-out Zale Moth Tier 2 X Waved Sphinx DN X White Tiger Beetle Tier 1 X White-tailed Diver Moth DN X Wild Indigo Borer Moth DN X Wild Indigo Duskywing DN X Wonderful Underwing Tier 2 X Yellow Banded Underwing DN X Yellow Stoneroot Borer Tier 1 X X X Yellow-sided Skimmer DN X Alewife Floater N/A X Brook Floater Tier x X X X X Creeper Tier 2 X Dwarf Wedgemussel Tier 1 X X X X X X X Eastern Elliptio Tier 2 X Eastern Lampmussel Tier 1 X X Eastern Oyster Tier 2 X

Appendix B. ROC List 23 August 2020 Habitat Management Plan for Bombay Hook National Wildlife Refuge

merica's Birds Birds merica's - Risk Species Species ic Conservation Priority Priority Conservation ic (RSGCN) State T & E FederalE T & Watchlist (2016) Watchlist Delaware SWAP SWAP Delaware BCR 3 Priority Species Priority BCR 3 XercesList Society Red of Management Concern of Management USFWS At NEPARC Species of Concern of Species NEPARC of Greatest Conservation Need Need Conservation of Greatest State of North A North Atlantic LCC Rare Plants Rare LCC North Atlantic NALCC Representative Species Representative NALCC NA Waterfowl Management Plan Management Waterfowl NA North Atlantic LCC Regional Species Species Regional LCC North Atlantic Delaware Wildlife Action Plan Species Species Plan Action Wildlife Delaware Fish and Aquat Common Name (2015)* Need Conservation of Greatest Birds Program Bird Migratory USFWS Eastern Pondmussel Tier 1 X X X Horseshoe Crab Tier 1 X Northern Lance Mussel Tier 2 X X Ribbed Mussel Tier 2 X Tidewater Mucket Tier 1 X X X Triangle Floater Tier 1 X X Yellow Lampmussel Tier 1 X X X Angular Disc Tier 2 X Armed Snaggletooth Tier 2 X Black Gloss Tier 2 X Carolina Physa Tier 2 X Channeled Whelk Tier 3 X Coastal Marsh Snail Tier 2 X Coastal Plain Tigersnail Tier 1 X Coastal-plain Ambersnail Tier 1 X Flamed Tigersnail Tier 2 X Flexed Gyro Tier 3 X Glass Spot Tier 2 X Gray-foot Lancetooth Tier 2 X Hairy Slitmouth Tier 2 X Honey Vertigo Tier 2 X Knobbed Whelk Tier 3 X Northern Threetooth Tier 2 X Obese Thorn Tier 2 X Ovate Vertigo snail Tier 2 X Pygmy Vertigo Tier 2 X Pyramid Dome Tier 2 X Rust Glyph Snail Tier 1 X Sharp Sprite Tier 3 X

Appendix B. ROC List 24 August 2020 Habitat Management Plan for Bombay Hook National Wildlife Refuge

merica's Birds Birds merica's - Risk Species Species ic Conservation Priority Priority Conservation ic (RSGCN) State T & E FederalE T & Watchlist (2016) Watchlist Delaware SWAP SWAP Delaware BCR 3 Priority Species Priority BCR 3 XercesList Society Red of Management Concern of Management USFWS At NEPARC Species of Concern of Species NEPARC of Greatest Conservation Need Need Conservation of Greatest State of North A North Atlantic LCC Rare Plants Rare LCC North Atlantic NALCC Representative Species Representative NALCC NA Waterfowl Management Plan Management Waterfowl NA North Atlantic LCC Regional Species Species Regional LCC North Atlantic Delaware Wildlife Action Plan Species Species Plan Action Wildlife Delaware Fish and Aquat Common Name (2015)* Need Conservation of Greatest Birds Program Bird Migratory USFWS Slender Walker Tier 2 X Snowhill Ambersnail Tier 1 X Swamp Vertigo Tier 2 X Toothed Hive Tier 2 X White-lip Dagger Tier 2 X Winding Mantleslug Tier 2 X PLANTS Amaranth, seabeach N/A X X X X Beaked-rush, Knieskern's N/A X X X X Dropwort, Canby's N/A X X X X Fimbristylis, Harper's N/A X X Pink, swamp N/A X X X X Pogonia, small- whorled N/A X X X X

* Delaware Wildlife Action Plan Tier definitions: Tier 1 = Species in the highest need of conservation action; Tier 2 = Species of moderate conservation concern in Delaware; Tier 3 = Species that are for the most part still relatively common in Delaware, but are listed as SGCN for various reasons, including documented population declines, high responsibility of the Northeast region for the global population, or continued need for monitoring and/or management; DN (DNs) = Species in need of monitoring efforts to determine their conservation status in Delaware.; Ext = Extirpated; N/A = Species does not appear in the SGCN list, or no Tier is assigned

Appendix B. ROC List 25 August 2020

APPENDIX C. BOMBAY HOOK NWR HABITAT MANAGEMENT PLANNING TEAM

Bombay Hook NWR Habitat Management Plan Planning Team

U.S. Fish and Wildlife Service Al Rizzo - Project Leader Coastal Delaware NWR Complex

Oscar Reed - Refuge Manager Bombay Hook NWR

Susan Guiteras - Supervisory Wildlife Biologist Coastal Delaware NWR Complex

Dan Stotts - Wildlife Biologist Bombay Hook NWR

Bart Wilson - Project Manager Coastal Delaware NWR Complex

Nancy McGarigal (Retired) Chief, Division of Natural Resources and Conservation Planning USFWS North Atlantic-Appalachian Region

Ava Smith - Assistant Refuge Planner USFWS North Atlantic-Appalachian Region

Meghan Powell - Natural Resource Planner USFWS North Atlantic-Appalachian Region

Austin Rizzo - Assistant Refuge Planner USFWS North Atlantic-Appalachian Region

Contracted Dan Salas - Senior Ecologist, ESA/Senior Consultant Cardno

Benjamin Mannies - Senior Project Scientist Cardno

Kristina Shope - Project Scientist Cardno

Amy Paulson - Senior Managing Associate Environmental Science Associates

Appendix C. HMP Team 1 August 2020