TIJUANA SLOUGH/SWEETWATER MARSH NATIONAL WILDLIFE REFUGES Imperial Beach, California

ANNUAL NARRATIVE REPORT

Calendar Year 1990

U.S. Department of the Interior Fish and Wildlife Service NATIONAL WILDLIFE REFUGE SYSTEM TIJUANA SLOUGH NATIONAL WILDLIFE REFUGE

IMPERIAL BEACH, CALIFORNIA

, ANNUAL NARRATIVE REPORT

CALENDAR YEAR 1990

U.S. Department of the Interior Fish and Wildlife Service NATIONAL WILDLIFE REFUGE SYSTEM REVIEW AND APPROVAL

TIJUANA SLOUGH NATIONAL WILDLIFE REFUGE

IMPERIAL BEACH, CALIFORNIA

ANNUAL NARRATIVE REPORT

CALENDAR YEAR 1990

L—JAUA /O/d^fV Refuge Manager Refuge Supervisor Date ^ Review INTRODUCTION

Sited in southern San Diego County, approximately one mile north of the United States/Mexico border, Tijuana Slough NWR encompasses 1,056 acres of saltmarsh, riparian, dune and upland habitats. Established in 1980, the Refuge includes the southern-most estuarine system (Tijuana Estuary) on the Pacific Coast of the United States, and represents one of the few remaining, relatively undisturbed tidally influenced wetlands in southern California.

The Refuge forms the northern half of the Tijuana River National Estuarine Research Reserve. The Reserve, established in 1982 under Section 315 of the Co&stal Pond Management Act, totals 2,531 acres. Overall Reserve management iiir^a cooperative effort primarily between the Fish and Wildlife Service and the California Department of Parks and Recreation.

Because the Refuge lies in proximity to the sixth largest metropolitan center in the United States (San Diego), and the most rapidly expanding urban site in Mexico (Tijuana), public use pressures remain intense throughout the year. Tijuana Slough supports numerous federal and state listed endangered species, including the California least tern, light-footed clapper rail, and the salt marsh birds beak. Priority management efforts are directed at minimizing public use impacts to these resources, enhancing the Estuary's tidal prism, and restoring degraded saltmarsh and dune habitat.

Marbled godwit foraging near the mouth of the Tijuana River. PR-12/88 < PAGE INTRODUCTION

TABLE OF CONTENTS 1

A. HIGHLIGHTS 1

B. CLIMATIC CONDITIONS 1

C. LAND ACQUISITION

fV Fee Title NTR Easements NTR 3. Other NTR

D. PLANNING

1. Master Plan NTR 2. Management Plan NTR 3. Public Participation 1 4. Compliance with Environmental and Cultural Resource Mandates .... 2 5. Research and Investigations 2 6. Other 5

E. ADMINISTRATION

1. Personnel ' 9 2. Youth Program 10 3. Other Manpower Programs NTR 4. Volunteer Program 10 5. Funding 11 6. Safety 11 7. Technical Assistance 11 8. Other 13

F. HABITAT MANAGEMENT

1. General 15 2. Wetlands 16 3. Forests NTR 4. Croplands NTR 5. Grasslands NTR 6. Other Habitats 18 7. Grazing NTR 8. Haying NTR 9. Fire Management 20 10. Pest Control 20 11. Water Rights NTR 12. Wilderness and Special Areas NTR 13. WPA Easement Monitoring NTR

i G. WILDLIFE * PAGE

1. Wildlife Diversity 20 2. Endangered and/or Threatened Species 21 3. Waterfowl 27 4. Marsh and Water Birds 27 5. Shorebirds, Gulls, Terns and Allied Species 27 6. Raptors 28 7. Other Migratory Birds 28 8. Game Mammals NTR 9. Marine Mammals NTR . lOX Other Resident Wildlife 28 ITV" Fisheries Resources 29 12, Wildlife Propagation and Stocking NTR 13. Surplus Animal Disposal NTR 14. Scientific Collections NTR 15. Animal Control NTR 16. Marking and Banding 29 17. Disease Prevention and Control 30

H. PUBLIC USE

1. General 30 2. Outdoor Classrooms - Students 30 3. Outdoor Classrooms - Teachers 31 4. Interpretive Foot Trails 31 5. Interpretive Tour Routes NTR 6. Interpretive Exhibits/Demonstrations 31 7. Other Interpretive Programs 32 8. Hunting NTR 9. Fishing 32 10. Trapping NTR 11. Wildlife Observation 33 12. Other Wildlife Oriented Recreation NTR 13. Camping NTR 14. Picnicking NTR 15. Off-Road Vehicling 33 16. Other Non-Wildlife Oriented Recreation 34 17. Law Enforcement 34 18. Cooperating Associations NTR 19. Concessions NTR

I. EQUIPMENT AND FACILITIES

1. New Construction 36 2. Rehabilitation 36 3. Major Maintenance NTR 4. Equipment Utilization and Replacement 36 5. Communications Systems 36 6. Computer Systems 36 7. Energy Conservation NTR 8. Other 37

ii • < J. OTHER ITEMS' PAGE

1. Cooperative Programs NTR 2. Other Economic Uses NTR 3. Items of Interest 37 4. Credits 38

K. FEEDBACK NTR

L. INFORMATION PACKET (inside back cover)

iii 1

A. HIGHLIGHTS

Visitor center dedicated. (See Section B.8)

Director Turner visits Refuge. (See Section E.8)

National Estuarine Research Reserve Managers Workshop hosted by Refuge. (See Section E.8)

Official liaison efforts with Mexico initiated, (See Section E,8)

The Pacific Estuarine Research Laboratory inaugurates a field laboratory on the Refuge. (See Section D.6)

Planning continues for proposed San Diego Bay and Vernal Pools National Wildlife Refuges." (See Section D.6)

B. CLIMATIC CONDITIONS

According to the U.S. Weather Bureau, local 1990 climatic data will not be available until at least June 1991,

Climatic conditions exemplify a coastal sub-tropical (Mediterranean) climate. Annual precipitation averages ten inches, with December to March typically receiving the most rainfall. Mean temperatures reach annual lows of 480F in winter and increase to 780F in July/August. Dominant winds are from the southeast during the winter and from the northwest in summer.

D. PLANNING

3. Public Participation

Tijuana Slough NWR is a component of the Tijuana River National Estuarine Research Reserve (Research Reserve).- The Research Reserve, established in 1982, includes land owned by the Fish and Wildlife Service (Service), the California Department of Parks and Recreation (CDPR), the U.S. Navy, and the County and City of San Diego. Under a 1984 Memorandum of Understanding (MOU), the Navy transferred management of their property (551 acres) within the Research Reserve to the Service. This MOU was up for official review in June 1989. At that time a letter was forwarded to the Navy requesting their official comments; a response was received nine months later.

The Navy proposed a number of modifications unacceptable to the Service, primarily relating to public use/education. A series of meetings will be needed to address these items, and until an accord is reached, the existing MOU will remain in effect.

Discussions were initiated during the period relative to incorporating an additional 50 acres of Navy property into the MOU.

To promote cooperative management efforts throughout the Research Reserve, an eight member group, the Reserve Management Authority (Management Authority) meets monthly to discuss complex resource issues affecting the area. The Management Authority is chaired by the CDPR, and includes representatives from the Service, the State Coastal Conservancy, the National Oceanic and Atmospheric Administration (NOAA), California Coastal Commission, County of San Diego, and the Cities of Imperial Beach and San Diego. Project Leader Ken Voget (Salton Sea) and Manager Marc Weitzel attend monthly meetings. Subcommittees have been designated to address specialized resource issues such as public use and research.

Because of the Research Reserve's proximity to the international border, and dtfif to the binational significance of numerous resource issues, the Management Authority has formally requested, via Mexico City, that Mexico appoint a permanent representative to attend their monthly meetings. Mexico will hopefully fill this position in the near future.

4. Compliance with Environmental and Cultural Resource Mandates

In late December, a comprehensive internal Section 7 Consultation relative to the proposed trail system was submitted to the Laguna Niguel Field Office (LNFO). The trail proposal has proven to be extremely controversial. Various entities are opposed, believing that we are inviting the public into resource sensitive areas; Research Reserve management staff view the action as an educational and public use control tool. During the period, Tijuana Slough NWR (Refuge) staff effected numerous trail coordination meetings with concerned groups, including University researchers, CDPR managers. Navy personnel and others.

A response was received from LNFO approximately eight months later. A number of constraints were outlined that the Refuge considered unacceptable, and a series of discussions and document revisions ensued to rectify differences. It is anticipated that by early 1991, an agreement can be reached so that formalization of our interpretive trail can be accomplished.

5. Research and Investigations

Since the 1970's, research interest in the Tijuana Estuary (Estuary) has increased exponentially, with emphasis centered around saltmarsh and dune communities. Research efforts have addressed the challenges posed by environmental changes and ecosystem responses. Studies have progressed from resource inventories and measurements of wetland processes to long-term comparisons of the effects of disturbances. Of priority concern is the determination of cause-effect relationships. The types of projects have shifted as the Estuary experienced new and different environmental assaults. All research proposals are evaluated by Refuge staff and submitted to the Regional Office for approval. Research efforts during the year included:

Refuge Personnel

a. Tijuana Slough Contaminant Reconnaissance Study

This project was initiated to determine concentrations of various contaminants in fish, birds/mammals, plants, invertebrates, and sediments. 3

The primary concern is the potential uptake of contaminants such as organochlorine pesticides and PCBs, trace metals, and aliphatics in the diets of resident and migratory birds, and other waterbirds in general. The Refuge is now ranked number two priority in the Region relative to contaminant assessment efforts. The 1990 sampling program was based on preliminary analytical results from the previous three years.

During the period, selected biota totalling approximately 100 samples were collected and catalogued from three stations within the Estuary and near the international border. Biological samples from a salvaged California light footed.clapper rail were secured. Fine grained sediments, fish, plant and invertebrate samples composed of killifish, gobies, topsmelt, scaulpin, pickleweed, bulrush, water hyacinth, gambusia, crayfish, African clawed frogs, mussels, and mud crabs were collected in July.

This year's contaminant sampling was effected by the Laguna Niguel Field Office Contaminant Specialist and staff, with assistance rendered by Wildlife Biologist McGill. Sampling will continue through at least FY 91,

Formal interpretation of 1990 results has not been accomplished; full results have not yet been received. Preliminary feedback show low levels of aliphatics and aromatics in this years samples of sediments and blue mussels. Results from 1989 data indicated a potential concern involving petroleum contamination (concentration of Aliphatic hydrocarbons) with clapper rails (see Section G.2c); 1990 data noted elevated levels of PCB and DDE (from one fat sample) in this same species.

Other Personnel

a. The integration of simulation modeling and saltmarsh monitoring for improved management at Tijuana Estuary

Joy Zedler, San Diego State University, Ted Foin, UC Davis.

Activities include developing a simulations model to predict interannual variation in vegetation, based on factors controlling plant growth. This project, involving the systematic sampling of saltmarsh flora, was initiated nine years ago. Efforts will continue into FY 91.

b. Fish and Benthic invertebrate dynamics: responses to wastewater influxes

Chris Nordby and Joy Zedler, Pacific Estuarine Research Laboratory.

Efforts include quarterly monitoring of fish and benthic invertebrate species composition to examine relationships between fauna and proximity to wastewater sources. Testing includes water salinity and oxygen, and assessing fish for heavy metal concentration. Funded by NOAA, this effort will continue through FY 91. 4

c. Pre-project studies for the Ti.luana Estuary Tidal Restoration and Wetland Enhancement Project

San Diego State University - numerous investigators.

Initiated in September, this effort will: a) establish the environmental baseline to assess any impacts associated with the project; b) outline project objectives; and c) establish post-project monitoring procedures. Efforts will continue into FY 91.

'd.. Cordylanthus maritimus ssp. maritimus experimentation within the Tijuana Estuary

Pacific Estuarine Research Laboratory.

Project will proceed into FY 91. Objectives include: a) improve Cordylanthus seed germination within the Refuge by clipping above ground biomass of associated flora to promote light penetration to the soil surface; and b) to assess the impact of sand substrate on seed germination and seedling survivorship.

e. Wastewater Wetlands: Pulsed discharges to protect coastal water bodies

Pacific Estuarine Research Laboratory.

Initiated in 1989, this effort will, within a controlled environment, manipulate the inundation/drainage regime of wastewater treated wetlands to assess their water quality improvement functions while also examining their impact on the salinity of downstream coastal systems when treated wastewater is discharged on outgoing tides. Efforts will continue into FY 91.

f. Linkages among estuarine habitats and with the watershed

Pacific Estuarine Research Laboratory.

Initiated in 1989, this project is investigating the relationship between estuarine habitats and the adjacent watershed, including interactions between the saltmarsh and its tidal creek. Water quality of the Tijuana River is being monitored as it enters and moves through the Estuary. Activities will progress into FY 91.

g. Assessing the sources and loading of pollutants affecting the Tiiuana Estuarv

Pacific Estuarine Research Laboratory.

This on-going effort is evaluating how the fish and invertebrate fauna is impacted from inflows from different watershed types, both quantitatively and qualitatively. h. Effects of density on shorebird foraging behavior and agfiresslon

D. Parker Chapman, San Diego State University.

Initiated in 1989, this effort is also in progress concurrently at Sweetwater Marsh NWR. This program will investigate the effects of density on shorebird behavior and aggression. Actions will continue into FY 91.

San Diego State University shorebird researcher, and assistant, in action. RR-1/90

6. Other

Visitor center related construction activities continued throughout the period. The Center, sited on Refuge property, is a Service/State Parks cooperative venture.

Landscaping visitor center grounds (approximately five acres), with native flora, was initiated during the year using volunteer assistance. Planting efforts will continue into 1991. Crews from the San Diego Job Corps Center installed the Center's underground irrigation system. Youth Conservation Corps enrollee Melendez planting native flora near Visitor Center. LF-7/90

Construction of the Center's garage/workshop/research lab was scheduled to commence during the year; however, the owner of an apartment complex adjacent to the proposed construction site filed suit against State Parks, in State court, to block the project (The Service was not named in this action.). The owner maintained that the construction of the 66 ft. length x 24 ft. wide x 15 ft. high structure would be in violation of the Coastal Zone Management Act and impact the public's ability to view the Refuge. The reality is that the appropriate documentation had been submitted to the California Coastal Commission (see Section D.4) and that only the occupants of one or two apartments would have their view of the Refuge partially obstructed. The owner was successful in securing a temporary restraining order that blocked implementation of the garage project. The State Court directed the Coastal Commission to hold a public hearing on the issue. The hearing was convened on 11 December; Manager Weitzel testified at the function. The Coastal Commission upheld their earlier endorsement of the project's Negative Determination and again ruled in favor. This ruling provided the "green light" for the garage project, and solicitation of contract bids was underway by the end of the year. It is anticipated that construction will begin in early 1991 even though rumor has it that the apartment owner is contemplating pursuing additional litigation.

Planning efforts relative to visitor center exhibitry continued throughout the period. The Regional Office's Division of Education, Publications, Information and Cultural Resources produced, in May, an attractive 7

"Interpretive Development Prospectus Summary" that discusses the exhibiting proposed for the Center, the interpretive trails and an anticipated overlook at Seacoast Drive. This document will be employed for fundraising efforts.

Functions relevant to visitor center matters, including Southwest Wetlands Interpretive Association (SWIA) quarterly/monthly meeting and Imperial Beach City Council meetings were attended, when possible, by Manager Weitzel.

Throughout the year, a number of meetings/discussions were effected to formalize an interpretive facility concept for the south end of Seacoast DfiVe.. A partial interpretive prospectus was developed by the Regional Office in 1988. This document outlines a general approach, including boardwalk/overlook; and panels emphasizing endangered species, saltmarsh/dune ecology, and active management themes. It is hoped that this project will come to fruition in the near future. Funding for this action, however, has not yet been secured. The San Diego Job Corps Center has expressed an interest in donating their carpentry crews to complete project construction.

Throughout the period, coordination meetings were effected between Refuge/Research Reserve and San Diego State University personnel to discuss details relative to relocating the Pacific Estuarine Research Laboratory (PERL) to Tijuana Slough. PERL, a function of San Diego State University, concentrates in research related to wetland restoration/creation. PERL is currently sited in the southern half of the Research Reserve along the international border. An increase in border violence has curtailed a significant portion of PERL's field efforts. Hence, a justifiable need exists to secure an alternate site for PERL's activities. Because PERL's research and restoration actions are compatible with Refuge objectives, it was felt that moving to Tijuana Slough, on a controlled basis, would be acceptable. The Refuge will evaluate PERL's relocation requests on a project by project basis. One effort, which will assess the role of wetlands in filtering wastewater received our permission in late 1989; construction of fencing and associated facilities relative to that project should be completed by mid 1991. "PERL Norte", as the new facility is called, was officially dedicated 12 January. San Diego State University's Pacific Estuarine Research Laboratory - North Unit was inaugurated in January. RR-1/90

Throughout the year, various coordination/planning meetings were completed relative to the Vernal Pools NWR proposal. For example, in May, Regional Office Realty personnel, LNFO and local refuge staff completed field inspections of vernal pool sites under consideration for inclusion into the proposal. The Service's Laguna Niguel Field Office assumed the lead in preparing the required environmental assessment (EA); Refuge staff assisted. The Preliminary Project Proposal was-endorsed by the Director in 1989 and pre- acquisition contaminant assessment surveys were completed that same year. Preliminary contaminant results indicate that no problem areas exist within the acreage targeted for acquisition; however, additional evaluations are planned next year.

The refuge proposal includes up to 3,020 acres of vernal pools, watershed and necessary upland buffers. Target areas are located throughout San Diego County, and acquisition will be accomplished via transfer of fee title acreage (from California Department of Transportation, for example), and establishment of overlay refuge relationships with entities such as the Navy (Miramar Naval Air Station) and the City of San Diego (Lindberg Air Field),

The draft EA was completed during the period; the final document should be available by late 1991. It is hoped that acquisition efforts can be initiated by mid-1992. Planning efforts relative to the proposed San Diego Bay (Bay) NWR continued at an aggressive pace throughout the period. Service Director John Turner approved the Preliminary Project Proposal in June. This endorsement opened the door for detailed planning efforts. The project could involve up to 2500 acres of estuarine habitat and upland buffer in the extreme southern section of the Bay.

At various times during the year, Regional Office Realty staff, along with local Refuge personnel met with interested landowners and other entities to explain aspects of the Bay proposal. While a large base of public support e^sts for this proposed refuge, concern has been expressed by a number of developers who would like to implement non-refuge type projects in the south part of the Bay.

Environmental groups such as the Sierra Club and Audubon Society are consolidating efforts to help market this proposal to the political community. These groups convene monthly at the visitor center to discuss progress. It is hoped that the environmental assessment can be completed by late summer of 1991, and that acquisition, which will probably prioritize cooperative management agreements with landowners, can be initiated by late winter of that same year.

E. ADMINISTRATION

1. Personnel

Marc M. Weitzel - Refuge Manager, GS-485-11 PFT: EOD 1/87 Ronnie L. Ryno - Refuge Operations Specialist, GS-485-09 PFT: EOD 8/89 Michael L. McGill - Wildlife Biologist, GS-486-05 TFT: EOD 6/90

Biologist McGill, retired from the Marine Corps and employed last year as a Biological Technician, graduated from San Diego State University in June. Our intent is to convert Mike to permanent status in the near future.

In January, two California Conservation Corps interns started working full time to address primarily facility maintenance actions. Supervisory responsibility is shared between the Service and State Parks.

Tijuana Slough is a satellite station of the Salton Sea NWR Complex, which is located in Imperial County, California, approximately 140 miles east of the Refuge. Most office/field duties are accomplished by on-site staff; however the Refuge does secure some administrative and maintenance support from Salton Sea, 10

2. Youth Programs

The 1989 Youth Conservation Corps (YCC) program, active from 25 June to 17 August, involved the following personnel:

Linda Foster - Social Services Assistant, GS-05; 18 June - 24 August Brandon Moody (Youth Leader) Jack Memea Librado Orduno Jennifer Melendez

The season was a resounding success. Taskings completed at Tijuana Slough and Sweetwater Marsh during the period included: collection of litter and flotsam, road maintenance, restoring dune protective fencing, removal of exotic vegetation, boundary posting, assisting with contaminant sampling, fencing (including erection of approximately three quarters of a mile of freeway type barricade around Sweetwater Marsh's F-G Street wetland.

1990 Youth Conservation Corps crew. Right to left: Crewleader Linda Foster; enrollees Jennifer Melendez, Brandon Moody and Librado Orduno. MW-8/90

4, Volunteer Program

Now that Refuge staff are located on an on-site administrative facility aggressive efforts are in progress to upgrade our volunteer support program. 11

Phillip C. Roullard, a San Diego County Park Ranger who also dabbles as a professional wildlife photographer and Tijuana Slough's first official volunteer, continued to supply the Refuge with high quality slides. Callie Mack, who owns a wildlife illustration business, concentrates her volunteer interests around exotic plant removal, general debris collection and other strenuous taskings. After another stint as the 1990 Social Services Assistant, Linda Foster continued as a volunteer, upgrading the Refuge's herbarium collection, which includes a fine photographic representation of local flora.

Iff^une, Olen Golden (State Park Ranger) and Mac McEachern (a State Park volunteer) signed on as volunteers to work on habitat restoration and facility maintenance projects.

In October, Patty Israel began volunteering her efforts, primarily towards refurbishing the station library.

While not official Service volunteers, numerous organizations, in particular scouting groups did donate their time towards litter pick-up or related actions.

5. Funding

The Refuge does not receive direct funding; refer to the Salton Sea narrative for Complex funding levels'.

The station maintains an imprest fund ($500.00); Manager Weitzel is the designated cashier.

6. Safety

All safety oriented literature received from the Regional Office and Complex headquarters was reviewed. Safety discussions were conducted as needed. Time permitting, formal safety meetings at- Salton Sea were attended. No accidents (to personnel or equipment) occurred during the period.

7. Technical Assistance

Manager Weitzel attended monthly Management Authority meetings and actively participated in decisions affecting the Research Reserve. Manager Weitzel is an agency advisor to the Pacific Estuarine Research Laboratory (PERL), the Southwest Wetlands Interpretive Association, the South Bay Land Use Task Force, and the United Nations Association "Environmental Committee for the San Diego-Tijuana Region". Biologist McGill attended Otay River Enhancement Committee meetings and Assistant Ryno is on the Tijuana River Valley Community Planning Group.

Throughout the 1991 California least tern nesting season (April - September), Refuge staff coordinated Tijuana Slough and Sweetwater Marsh NWRs monitoring efforts with CDFG contract biologists (see Section G.2d). Assistance was also provided to a CDPR ecologist overseeing California light-footed clapper rail winter high tide surveys and spring call counts. 12

The first phase (EIS and permit preparation) for the long-term, multi-agency, $40 million "Tijuana Estuary Tidal Restoration and Wetland Enhancement Project" was initiated in 1988. San Diego State University received a disbursement of almost'$300,000 from the California Coastal Conservancy to complete the needed environmental assessment documents/permits. The Service agreed to become the Federal lead agency during the EIS development process; the Corps of Engineers was incorporated as a co-Federal lead this year.

The preliminary draft environmental impact statement (PDEIS) for the project . was available for review in September 1989. After conferring with the Coastal Conservancy, the State lead on this project, it was decided that the PDEIS did not sufficiently comply with NEPA/CEQA impact statement format. Hence, the University is being required to dramatically modify the PDEIS; the revised version will probably not be available until mid-1991. Refuge staff participated in various project coordination meetings during the period.

Additional items of interest include:

In March, Manager Weitzel reviewed the PDEIS relative to endangered species management at Seal Beach NWR.

In May, Refuge Operations Specialist Ryno provided the Air Force with information regarding BASH at Tijuana Slough and Sweetwater Marsh Refuges.

In September, Ryno met with the Navy's local natural resource staff to discuss proposed wetland restoration projects relative to a 55 acre parcel to be transferred to the Refuge.

In November, Weitzel provided management recommendations to the Friends of Famosa Slough and the City of San Diego regarding the City's new Famosa Slough Reserve. Also that same month, Weitzel presented wetland restoration advise to the Navy regarding their Radio Receiving Station, Imperial Beach; and Ryno and Salton Sea NWR's Biologist B. Radke met with the Navy to discuss a draft vernal pools management plan for Miramar NAS.

In December, Ryno assisted with the Christmas Bird Count and waterfowl hunting season law enforcement efforts at Salton Sea.

At mid-year. Manager Weitzel initiated efforts to develop strong professional bonds with the conservation community in Baja California (Baja).

Priority objectives of this liaison program include: a) Enhance the working dialogue between the U.S. Fish and Wildlife Service (Service) and Mexico. b) Address resource issues specific to the Service's Region 1 border zone and Baja, such as those related to water quality, transportation of wildlife artifacts and binational monitoring of endangered species. c) Accommodate provisions of Service-wide endeavors, including the North American Waterfowl Management Plan and training aspects of the Western Hemisphere Program. 13

To accomplish program objectives routine contact was maintained with various institutions in Baja, including appropriate offices of the Secretaria de Desarrollo Urbano Y Ecologia, a private sector binational environmental group called Pro Esteros, and other entities such as the Centro de Investigacion Cientifica y Educacion Superior de Ensenada and the Universidad Autonoma de Baja California. Basic activities involved exchanging technical literature, providing or participating in special training and routine travel across the border to discuss mutual management concerns. Issues related to migratory birds, refuge operations/land management, endangered species, contaminants and laiw enforcement were addressed.

This liaison project is expected to continue on an indefinite basis. Projected actions include establishing a binational wetlands advisory council and developing a land use plan for Baja's Punta Banda Estuary. Punta Banda has been proposed for reserve designation.

8. Other

Noteworthy events included:

On 19 January, Deputy Region 1 Director Bill Martin visited the Refuge. Weitzel presented an overview of the Refuge, the San Diego Bay NWR proposal and proposed liaison efforts with Mexico.

On 6 February, Service Director John Turner, Region 1 Director Marv Plenert, Southern California Field Station Supervisor Jeff Opydycke and Special Agent in charge Larry Farrington visited the Refuge and received an overview of refuge activities in San Diego County from Weitzel.

Director John Turner and Regional Director Marv Plenert receive briefing from Manager Weitzel at the Refuge in February. RR-2/90 14

The annual station inspection was effected by California/Nevada Associate Manager Bob Fields on 8-9 February. Efforts included a visit to the proposed Vernal Pools NWR site at Miramar NAS and discussions relative to creating a Southern California coastal refuge complex based out of Tijuana Slough.

On 23 March, Rob Shallenberger, Deputy Assistant Regional Director/Refuges and Wildlife, Region 1, visited the Refuge.

The Tijuana Estuary Visitor Center was officially dedicated on 12 May. Approximately 400 people attended, including members of the political community. Region 1 Assistant Regional Director John Doebel represented the Service,

John Doebel, Assistant Regional Director - Refuges and Wildlife represented the Service at May's Visitor Center dedication. PR-5/90

On 2 July, Project Leader K. Voget (Salton Sea NWR) and Weitzel attended a meeting with Representative Duncan Hunter's aide. City of Imperial Beach officials and various environmental activities to discuss impacts to the Refuge caused by helicopter activity from the adjacent Navy Outlying Landing Field.

On 6 July, Janet Carroll, Editorial Assistant, "Fish and Wildlife News" was on-site to accrue information for a future article on Tijuana Slough and Sweetwater Marsh. 15

In October, the 1990 National Estuarine Research Reserve Manger's Workshop was held at the Refuge. Approximately 40 Research Reserve staff members from throughout the U.S. attended. The conference's theme revolved around restoration and research.

From 28-31 December, noted photographer Tupper Ansel Blake was at the Refuge securing photos for an upcoming Smithsonian sponsored book celebrating the 100th year anniversary of the monumenting of the U.S./Mexico border. ir. —Special Use Permits issued during the period were as follows:

— - 28 August - 31 October; Delbert A. La Rue; to collect Cichdela tiger beetles.

01 May - 30 April 1992; Pacific Estuarine Research Laboratory; construct and maintain tidal channels as a component of PERL Norte.

21 June - 20 June 1991; City of Imperial Beach; continued use of a designated portion of Refuge as a "T-Ball Field".

10 April - 31 October; Liz Copper and Assistants; to monitor California least tern nesting actions.

11 November; Richard Hansen; one day permit to photograph from kayak.

05 November - 31 December; San Diego County Parks; to run "Wildlife Trek Program" in conjunction with the Zoological Society of San Diego.

F. HABITAT MANAGEMENT

1. General

The following habitat types are found within the Refuge:

a) Upland Zones. Best classified as coastal sage scrub and modified grasslands, indicator species includes California sagebrush (Artemisia californica). flat-top buckwheat (Eriogonum fasciculatum) and lemonade-berry (Rhus integrifolia). Within the Refuge, this zone is primarily impacted by trampling from illegal alien foot traffic from Mexico.

b) Riparian and Brackish Marsh. Represented by flora such as willows (Salix sp.), saltcedar (Tamarix SP.) and cattail (Tvnha SP.). Within the Refuge's riparian corridor, nesting pairs of the federally listed least Bell's vireo (Vireo bellii pusillus) have been recorded.

c) Salt pannes. These areas are found adjacent to mud and high saltmarsh habitat. Salt pannes are inundated during the winter; however, due to evaporation, these areas are dry and covered with a salt crust in summer. Winter bird use of this habitat during the aquatic phase is substantial. 16

d) Upland/Wetland Transitions. A zone, indicated by both saltmarsh and coastal sage scrub flora, including flat-top buckwheat, coastal cholla (Opuntia prolifera), saltgrass (Distichlis spicata), and alkali health (Frankenia grandifolia). This zone has been historically exposed to substantial pedestrian traffic; however, through increased law enforcement and environmental awareness efforts, visitor use impacts to this habitat type have been reduced.

e) Intertidal flats. These include the sand and mudflat areas exposed during . lc^ tide. This habitat type is used extensively by the shorebird community ftJr'" foraging and loafing; bird densities are highest in the winter.

f) Dunes/Beach. A dynamic habitat, subject to numerous disturbances, such as human trampling of vegetation, and assorted public use impacts to beach/dune nesting avifauna, including the California least tern and the western snowy plover. Sand verbana (Abronia maritimia) and dune ragweed (Ambrosia chamissonia) are typical native dune plants.

g) Salt Marsh, The Refuge administers 85 percent of the 1,255 acres of critical saltmarsh habitat within the Research Reserve. Typically the zone is subclassed as either low, middle or high marsh. An elevational range of approximately five feet separates the low marsh from the high marsh wetland zone. The low marsh (that area around mean sea level) is dominated by cordgrass (Spartina foliosa) a species which requires daily tidal inundation. Cordgrass provides dense dover and nesting material for the light-footed clapper rail. The intermediate zone, from mean high water to approximately mean higher high tide, is dominated by perennial pickleweed (Salicornia virginica). The middle marsh is biologically rich and supports the nesting efforts of the Belding's savannah sparrow (Passerculus sandwichensis beldingi). a species listed by the state of California as endangered. The high marsh zone, from mean higher high tide to extreme high tide, is indicated by flora such as shoregrass (Monanthochloe littoralis). perennial glasswort (Salicornia subterminalis). and alkali health. The endangered saltmarsh bird's beak (Cordvlanthus maritimus -spp. maritimus) can be found in the high marsh.

The Tijuana River bisects the Refuge and flows easterly through sand dunes to the Pacific Ocean. The River transports untreated wastewater, up to 12 million gallons daily, from Tijuana, Mexico, to the ocean. Efforts are in progress to alleviate this situation; however, because of the international ramifications of this issue, a simple solution is not forthcoming. Assessments relative to the long-term effects of this effluent load on Refuge resources are lacking; short-term impacts have not been noted. In fact, it appears that the increased nutrient load resulting from the intrusion of wastewater is creating a positive influence on the growth of wetland flora located within the River corridor.

2. Wetlands

Priority habitat management efforts are directed at enhancing the Estuary's tidal prism (flushing capacity). Adequate tidal flushing is considered the key to the health of the entire system. Reduction in tidal prism can threaten 17 the status of all resources associated with the Estuary. Over the years, the Service has been actively involved in maintaining and increasing the tidal prism.

During the winter of 1982 and 1983, violent storms impacted the coast of southern California. Resulting storm surge accreted large volumes of sand, overwash from the barrier dune system, into the Refuge's primary flushing channel, the Oneonta Slough. This sand deposition depressed tidal flows, and the resulting reduction in ebb tide scouring caused periodic closure of the Tijuana River mouth. This situation created various management problems rtffatiye to endangered species and their habitats. In addition, three dams on the Mexican side of the Tijuana River substantially reduced the River's flow. This reduced flow and tidal flushing eventually caused extreme changes in the saltmarsh community, including severe impacts to the saltmarsh bird's beak and light-footed clapper rail. The longest closure of the River's mouth, with a complete absence of tidal flushing, occurred from April - December 198A. This eight month closure had a devastating effect on the Estuary; tidal channels became hypersaline, shallow creeks evaporated, and the substrate turned to brick. Soil salinity was recorded at greater than 100 ppt in September 1984, and this caused a substantial die-back of salt marsh vegetation.

From 1982-84, staff from Salton Sea NWR made several attempts to open the River's mouth; however, after each effort, the ocean established a sand bar across the mouth and, within hours, tidal flushing was again restricted or blocked. From September 1984 to January 1985, to increase tidal prism and open the mouth. Refuge staff dredged over 6400 cubic yards of sand/sediment from Oneonta Slough. Tidal flushing was again reestablished. From January to April 1985, dredge spoil was used to refurbish the barrier dune system. On 1 February 1986, the River's mouth again became blocked with sand due to extremely high winds and nearshore waves, accompanied by high tides. On 4 February, dozer work again restored tidal flushing. The mouth of the Tijuana River has since remained open, with continued tidal flushing throughout the year. Low marsh vegetation is once again exhibiting vigor.

To further enhance the Estuary's tidal prism, contract dredging was initiated in March 1987. The contractor Northbilt, Inc. (Lake Tahoe, CA) dredged MOOO ft. of Oneonta Slough and repaired a 700 ft. breached section of the barrier dune. Dredging was accomplished via dragline. Spoil, (about 50,000 cubic yards) was stockpiled along the western side of the Slough. Because of least tern nesting season (April - September), the operation was curtailed on 08 April 1987. Under a new contract, efforts were reinitiated on 19 October 1987, The new contractor, Gyro Engineering accomplished the following: a) approximately 200 ft of the west bank of the Slough was widened by up to 25 ft, and sloped at .+3:1; b) a backdune system was constructed; c) to facilitate drainage of any overwash, a gradient was created from the landward base of the backdunes to the Slough; d) the seaward aspect of the barrier dune was refurbished; e) light colored sand was deposited around the perimeter of one of the historical least tern nesting sites, thus increasing potential nesting habitat for the species; and f) grading down substrate north of the Seacoast Drive entry gate to expose the area to tidal action. After initial contractual requirements were completed, a substantial amount of surplus hours existed. To utilize these hours, the contractor redeplqyed his equipment to 18 the 5th and Iris area to complete the following: a) dozer removal of exotic fennel; b) regrading the maintenance road; c) assisting Refuge staff in excavating a runoff catchment basin; and d) bridging a section of Scirpus marsh with fill generated from the Refuge quarry site. The "bridge" was constructed so that a portion of the old maintenance road could be rerouted away from a more sensitive upper marsh zone. That segment of the old maintenance road which had traversed the upper marsh was then ripped with a dozer to promote revegetation. Gyro Engineering completed their Refuge work on 29 December 1987.

IfT'september 1988, a detailed assessment, "The Effect of the Oneonta Slough Dredge Project on Tidal Circulation and Entrance Channel Closure Conditions", was received from consulting hydrologists Phil Williams and Associates/San Francisco. The report summarized that 1987 tidal prism enhancement efforts (i.e. dredging) had been very successful. Numerous improvements had been accomplished such as increasing tidal range by 1,2 feet and enhancing ebb tide velocity by 3.0 ft./second. These conditions have helped to ensure proper scouring at the mouth, which, in turn, contributes dramatically to maintaining or increasing tidal circulation within the Estuary. Maintenance dredging has not been needed since the 1987 effort.

In April 1987, a wetland mitigation project (Shelter Islands Yachtways Boatyard) was completed. Actions included creating +_ 8,000 sq. ft. of intertidal habitat, widening an existing levee by 20 ft., transferring all spoil to a county landfill, and relocating vegetation that would have been impacted by dredging efforts to an adjacent area within the Refuge, This project had been initiated a year earlier; however, adverse weather had delayed its completion. By the end of 1990, the translocated vegetation had not established itself. This mitigation effort is not considered a success by the regulatory agencies.

During September, Refuge staff evaluated a report from the Boca Rios Homeowners Association (condominium owners at the south end of Seacoast Drive) to rearrange the Associations beach riprap. This action would impact a portion of riprap sited on Refuge property. That same month, coordination on the subject was initiated with the California Coastal Commission. In October, the Refuge gave formal permission to the Homeowners Association to proceed with the project. Activities will commence early next year.

6. Other Habitats

In December 1987, in preparation for a revegetation project, a work detail from Salton Sea NWR used a grader to scarify numerous trails and roads within the coastal sage scrub/grassland zone. These specific trails/roads were considered obsolete relative to Refuge operations. Later that month Refuge staff began seeding these areas with appropriate species. The seeds were raked in, and efforts were coordinated with rainfall to the extent practicable. Because of unanticipated heavy precipitation occurring shortly after seed placement, it is known that much of the seed stock was washed off of the seed project site and into tidal channels. Some success has been noted. 19

As previously outlined, maintaining a strong barrier dune is a key factor in precluding sediment deposition resulting from wave overwash into tidal channels. In addition, the presence of these dunes tends to direct visitors to the intertidal beach areas, and thus, reduce public use in the more sensitive habitat landward of the dune system. In late November - early December 1987, in conjunction with dredging efforts, contractors (Gyro Engineering) used the spoil generated from their activities to restore eroded segments of the barrier dune, and construct a backdune system. The seaward face of the barrier dune, however, was refurbished using intertidal beach sand that had accreted during the fall and winter months. The backdunes were constructed as a second line defense against major storm surge. All efforts were accomplished with one front-end loader and one crawler dozer.

The barrier dune system (+. the first 1,000 ft., from Seacoast Drive south) was heavily damaged by severe storm surge in January 1988. By mid-March of that year, an emergency storm damage repair contract had been let to effect the following taskings: restore damaged barrier dunes, reshape back dunes, remove storm generated debris from the Seacoast Drive entry road, redeposit light colored sand on the perimeter of the California least tern nesting site, and dredge out a sand plug (a product of storm surge) blocking an important flushing channel located just south of the River's mouth. These projects were satisfactorily completed by the end of March 1988 by Gyro Engineering. Even though the barrier dunes were severely damaged, they played a very significant role in precluding storm generated overwash into Oneonta Slough; thus overall tidal prism was not reduced.

During the current period, dune restoration/maintenance efforts were not required.

In an attempt to stabilize the barrier dunes, and in particular the new back dune system, PERL was contracted, in 1988, to complete revegetation efforts during that year's growing season. The Refuge purchased and installed a drip line irrigation system in January 1988; and reinstalled the system after it had been damaged by the severe January storm. Under the provisions of the $2,450.00 revegetation contract, PERL was required to: a) plant 800 nursery plants, including Encelios californica. Lotus nuttalianus, and Ambrosia chamissonis. b) at specified locations, seed species such as Chamissonia cheiranthifolia. Abronia maritimus and Ambrosia bipinnatifida, c) thin multiple germinations to one seedling, d) monitor drip line irrigation and e) submit a project summary report.

PERL's contractual requirements were completed to satisfaction by mid fall of 1988, Assessments at that time indicated that approximately 675 beach strand and dune scrub plants had been established as a result of this revegetation project. If human trampling impacts can be controlled, these plants can become established and thus contribute to maintaining this vitally important, protective dune system. Recent monitoring indicates that numerous strands of Abronia and Chamissonia have become well established. 20

9. Fire Management

In June, a small (+ 50 sq. ft.) brush fire near the 5th and Iris Street area of the Refuge was suppressed by the San Diego Fire Department. The fire had evidently been set by juveniles; no suspects were apprehended.

10. Pest Control

At least 11 species of mosquitos occur within the Estuary. Because of their potential as pests and disease vectors (malaria and encephalitis), and due to tTTe"' proximity of the Refuge to urbanization, a formal mosquito control plan is in effect. Under the provisions of this document, the Vector Control Division, County of San Diego, assumes all control measures; however, they must coordinate their actions with the Refuge office. The control plan outlines procedures for source reduction, larviciding and sets minimum levels of mosquito breeding before treatment is initiated. Infrequent use of the larvicide, "Golden Bear", a fast dissipating petroleum product that does not impact non-target resources, is permitted within the Refuge/Research Reserve. Fogging (adulticiding) is not allowed. Currently, Refuge staff are working with Vector Control to encourage the use of biological controls, including Bti.

G. WILDLIFE

1, Wildlife Diversity

Within the Refuge, the intertidal salt marsh and tidal channels of the Estuary provide wildlife habitat for a variety of birds, fishes and invertebrate species. As previously stated, the federally endangered light-footed clapper rail is found within the lower salt marsh while the state endangered Belding's savannah sparrow occurs in the pickleweed-dominated middle and upper marsh areas. The California least tern is frequently observed foraging within the Estuary's tidal channels. Upland habitat provides foraging opportunities for many birds, reptiles and small mammals. Raptors such as the northern harrier are frequently observed in these areas. Small mammals such as deer mice, rabbits and ground squirrels provide a food base for these and other birds of prey.

The coastal sand dunes and intertidal beach habitat offers important foraging, roosting, and nesting areas for numerous shorebirds. As mentioned, both the endangered California least tern and the western snowy plover nest on the sandy beaches and dunes of the Refuge. Migrating and resident shorebirds forage within the intertidal beach areas. 21

2. Endangered and/or Threatened Species

SPECIES STATUS*

California Brown Pelican FE, SE American Peregrine Falcon FE, SE Light-footed Clapper Rail FE, SE •California Least Tern FE, SE =fefSast Bell's Vireo FE, SE Belding's Savannah Sparrow Federal Candidate, SE Salt Marsh Bird's Beak FE, SE

*FE = Federal Endangered SE = State Endangered

a) California Brown Pelican

This endangered bird typically occurs along the California coastline where it forages and roosts. At the Refuge, their numbers increase in the summer months to 150 individuals. They are generally observed roosting at the Tijuana River mouth. No nesting activity occurs on the Refuge; however, breeding is documented from the nearby Coronado Islands, Mexico.

b) American Peregrine Falcon

Although this falcon historically nested along the San Diego coastline, recent nesting activity within the County, near the Coronado Bay Bridge, has been documented. A hacking program for these birds is currently underway on the Point Loma peninsula, approximately 12 miles north of the Refuge. Individuals of this species are infrequently observed within the Estuary, particularly near mudflats, shores or ponds where,water birds congregate.

c) Light-footed Clapper Rail

This secretive bird is endangered throughout its range due to the critical decrease in salt marsh habitat in Southern California. The rail population which occurs within the Estuary has been the subject of study since 1975 and its occurrence in the area is monitored regularly. Census (vocalization counts) activities for these birds were conducted in March/April 1990. A winter high tide count was conducted on December 1. Results of these counts, and prior surveys for the Refuge are listed below. It appears that the birds are rebounding from the previous years when closure of the River mouth (late 1984-early 1985) resulted in severe habitat loss and degradation in the Estuary, Spring surveys in 1988 indicated a rather abnormal number of unbonded individuals, at least when compared to rail populations at other sites in southern California; however, this situation was not noted during 1989 nor 1990 spring census efforts. Encouragingly, only two lone advertising females were heard during the 1990 spring census. As outlined in Section D,5, analysis of 1988 contaminant samples (rail eggs) indicated an alarmingly high

— 22

level of petroleum hydrocarbons. Are pollutants adversely impacting pairing efforts? This years contaminant program evaluated this issue in greater detail; assessment results, however, are not yet available. Results are available for a rail (fat sample) killed by a cat in 1989. It contained detectable but low levels of aliphatic and aromatic hydrocarbons and elevated levels of PCB and DDE,

CENSUS OF LIGHT-FOOTED CLAPPER RAIL AT TIJUANA SLOUGH MARSH (minimum numbers)

YEAR NUMBER OF PAIRS INDIVIDUALS WINTER HIGH TIDE COUNT

1982 25 — —

1983 41 — 36

1984 38 — —

1985 0 4 -

1 1987 15 40 40

1 1988 14 37 17

| 1989 16 49 oo

1 1990 19 42 82

In January, with assistance from the Southwest Working Group (Patuxent), based in Ventura, California, the Refuge completed its second banding exercise with clapper rails. Six birds were captured using canoes and dip nets during a winter high tide; a fairly labor intensive venture. A 1.0 cc sample of blood was also collected from each bird to evaluate genetic composition. 23

California light-footed clapper rail banding efforts. Dip nets were employed to capture rails. MW-1/90

Late in 1989 Refuge staff noticed a Northern harrier attempting to take a light-footed clapper rail. This was cause for some concern as it was believed that harriers do not prey upon clapper rails in Southern California. In January 1990 such observations were becoming common place. During the rail banding episode described above, a Refuge volunteer intervened and caused a female harrier to release a clapper rail as the hawk attempted to kill the rail. This was assumed to be an isolated case until wintering harriers returned in late 1990. On 15 November a female harrier was observed killing and consuming a clapper rail. On 01 December, Refuge Operations Specialist Ryno saw a female harrier kill and eat a clapper rail. While she was still feeding, at least two and possibly three other Northern harriers repeatedly tried to take rails. In an attempt to alleviate this predator problem, raptor consultant Pete Bloom was contracted through the Laguna Niguel Enhancement office to live trap harriers. This resulted in an immature female harrier being trapped on 14 December and released the next day at Cibola NWR,

d) California Least Tern

The California least tern is a migratory species, with breeding activity in southern California occurring between April and September. This endangered bird has suffered a significant decline in numbers due to loss of nesting habitat and feeding areas, general disturbance of nesting efforts and depredation. Least terns have been documented as nesting in the Tijuana River 24 area since 1962. Their numbers have remained somewhat sporadic from year to year as indicated below:

CALIFORNIA LEAST TERN NESTING DATA AT TIJUANA SLOUGH NWR

YEAR NUMBER OF NESTS FLEDGLINGS 1

1982 21-30 17+ 1 1983 60-65 50 + 1984 50-66 12-20 1985 41 18-20 1986 36-41 25-40 1987 46+ 13-19 1988 70+ 18+ 1989 79 21-31 O i—i 96 22 (13-39)

Generally these birds nest on the sandy beach to the south of the Tijuana River/Ocean interface and in an area north of the mouth and landward of the barrier dunes; however recent use of the beaches immediately north of the mouth has been documented. In 1990, both the northern and southern dune/beach areas were utilized for nesting. Nesting efforts were monitored primarily by and contract personnel from CDFG; Refuge staff do assist in completing end of season reports. A meeting held with CDFG/contract personnel to coordinate least tern monitoring efforts was accomplished in February. Because staffing level constraints preclude the Refuge from addressing least tern concerns in detail, this assistance from CDFG is highly appreciated. Least terns were observed in the area on 10 April; nesting activity began by early May, Ninety-six nests were recorded during the 1990 season. Many of the nesting pairs were unsuccessful during the season and renesting was suspected at both sites. Although both north and south nesting sites are clearly posted and the northern site "fenced" with a strand of wire between signs and the southern area partially protected by a field fence, human disturbance to the colonies remained a very significant problem. Illegal alien traffic, particularly at the site south of the River mouth, essentially destroyed that nesting colony. There were unconfirmed reports of illegals "egging" at this southern site. Equestrian traffic is an additional problem for the south colony. The northern colony receives pressure from recreational beach users, some illegal fishing activity, uncontrolled dogs, illegal alien traffic, and infrequent off-road vehicular traffic. Other than to post a 24-hour armed guard at these sites, there is no possible way to contain these public use problems. Increased educational efforts along with an on-site presence offer some long- term solutions to this resource protection issue. 25

Members from the California Conservation Corps install fencing around California least tern nesting grounds in April. MM-4/90

e) Least Bell's Vireo

This vireo was once commonly found throughout southern California and parts of Mexico, nesting in riparian woodland habitat found along rivers and streams. This population has declined substantially since 1920 as a result of brood parasitism by brown-headed cowbirds, and destruction of up to 95% of its critical habitat due to farming practices and development pressures. The current population of these birds within the Refuge is found south of the Naval Outlying Landing Field along the Tijuana River. Staff level constraints have precluded efficient monitoring of this resource; however, with an additional assistant manager on board, greater effort can now be directed towards monitoring this species. 26

San Diego State University workers surveyed the Tijuana River Valley, including the Refuge, weekly between 8 April and 31 August 1990. On the Refuge, only one male was observed (a transient who was present for one day).

Beginning in 1991, the Refuge will initiate a cowbird removal agenda.

f) Belding's Savannah Sparrow

This bird is a year-round resident of coastal salt marshes preferring the mid- u^er zones of southern California, including the Estuary. It is considered endangered by the State of California and is a federal candidate for listing. A 1986 nesting survey by biologists from the Laguna Niguel Field Office recorded 225 pairs within the Estuary; 160 of these were found along the Oneonta Slough. This large number of pairs is attributed to an increase in suitable elevations for nesting as a result of reduction in tidal flow within the Estuary due to closing of the River mouth in 1984. Surveys were not effected again until this year. San Diego State University personnel assumed the lead in the 1989 effort, 320 pairs were noted, primarily concentrated south of the Tijuana River mouth. University personnel again surveyed the Refuge in 1991 - 299 pairs were noted and 211 individuals (pairs?) were recorded.

g) Salt Marsh Bird's Beak

This endangered plant occurs in patches throughout the northern portion of the Refuge. Encountered in the high marsh zone, this species is subject to trampling by Refuge pedestrian traffic. The bird's beak is an annual, and the establishment of yearly population numbers is contingent upon seed dispersal. The plant is hemiparasitic on the roots of species such as pickleweed and alkali health. Flowering typically occurs April through June. To update distribution patterns, extensive surveys are conducted in Spring of each year. 27

3. Waterfowl

One aerial waterfowl survey was conducted that encompassed the Refuge. The results of this 05 January effort are listed below:

AERIAL WATERFOWL SURVEY, TIJUANA SLOUGH NWR, JANUARY 1988

>. SPECIES JANUARY JANUARY JANUARY JANUARY 1987 1988 1989 1990

Coot 130 245 205 185

Canada Geese — 02 — —

Mallard — 15 60 15

Gadwall — 15 75 — American Wigeon 400 565 535 345

Green-winged Teal — 265 45 75

Blue-winged/Cinnamon Teal — 05 20 — Northern Shoveler 150 40 90 190 Pintail 225 490 230 170

Redhead — 10 — 10

Canvasback 35 10 — —

Scaup — 35 20 — Bufflehead 05 30 05 15

Scoter — 65 05 —

— Merganser — 05 —

Ruddy 45 —

Ground surveys were conducted throughout the year by Refuge staff. American coot, lesser scaup, American wigeon, and northern pintail were the most common waterfowl wintering within the Tijuana River Valley, The month of December and January generally afford the highest counts of these and other species. Other waterfowl sighted include ruddy duck, red-breasted merganser, black brant, cinnamon and green-winged teal and bufflehead. Known nesters within the Estuary include mallard, ruddy duck, northern pintail, American coot and cinnamon teal.

4. Marsh and Water Birds

The mudflats and saltmarsh zones of the Estuary provides water birds with important foraging and loafing areas. Herons (including the little blue heron), egrets, cormorants, ibis, grebes, sora and others all make extensive use of the Refuge's estuarine environment. There are no known nesting colonies of herons or egrets within the Refuge; however, rookeries of wood storks, egrets, and herons are located within the Tijuana River Valley.

5. Shorebirds. Gulls. Terns and Allied Species

Shorebird numbers generally increase during the fall and winter months. Marbled godwits and willets comprise a large fraction of these birds. Other 28 species include: dowitchers, dunlin, long-billed curlew, plovers, American avocet, and black-necked stilt. These birds are generally observed foraging or loafing on tidal mudflats within the Estuary or along the shoreline, Caspian, elegant and fdrster's terns are common throughout the summer months. A newcomer to the area, a gull-billed tern, was sighted within the Refuge in July 1987; individuals nested in south San Diego Bay during the 1988, 1989 and 1990 breeding seasons. Black skimmers, which also nest in south San Diego Bay, were often observed in the summer foraging in tidal channels. Numerous gulls are found within the Refuge, the most common being western, California, Heermann's and ring-billed gulls.

6. Raptors

Northern harrier, American kestrel, red-tailed hawk, black-shouldered kite and an occasional short-eared owl and great-horned owl were sighted foraging within the Refuge in 1990. Osprey are common in the area during spring and fall migration. American peregrine falcons also frequent the Refuge during fall and spring months.

7. Other Migratory Birds

Of the 380 birds recorded for the entire Tijuana River Valley, 303 are considered migrants or visitors (non-breeders). Avifauna represent the primary group of sensitive wildlife recorded in this area, many of which are migratory and federal candidate species such as the reddish egret, long-billed curlew, and the savannah sparrow.

10. Other Resident Wildlife

The Refuge provides habitat for other groups of wildlife such as mammals, invertebrates (both marine and terrestrial), as well as reptiles and amphibians. Examples of these groups include: mammals - bobcat, striped skunk, raccoon, long-tailed weasel, desert cottontail, black-tailed jackrabbit, deer mouse and coyote; herptiles - western fence lizard, gopher and king snakes, San Diego horned lizard, Pacific tree frog, and western toad. Over 100 marine invertebrates have been recorded from the Estuary's tidal creeks, channels and mudflats. The Refuge and surrounding areas host over 2000 species of insects, several of which are federal candidates for listing as endangered or threatened. 29

Behr's Metalmark, a component of Tijuana Slough's insect fauna. PR-6/90

11. Fisheries Resources

The Estuary's channels support an important fishery resource within the Refuge, The distribution and abundance of the fishes is dynamic, responding to the variable tidal and flood regimes of the area. Up to 29 species of fish have been recorded for the Estuary, dominated by arrow goby fish, topsmelt, and California killifish. Monitoring of fishes and benthic invertebrates of the Estuary is regularly conducted by the PERL, with funding provided by NOAA.

16. Marking and Banding

A clapper rail banding effort was effected in January (see Section G.2c). In addition, as part of a San Diego State university sponsored shorebird study (see Section D,5h), researchers banded 11 sanderlings and nine sandpipers. 30

17. Disease Prevention and Control

As outlined in F.l, renegade wastewater from Mexico flows into the Estuary, primarily via the Tijuana River. The longest influxes occur as sewage spills which have the potential of discharging industrial/toxic compounds into the Estuary. As yet, there has been no documented disease outbreaks within the Refuge, but the potential is high due to the discharges from Mexico and other sources, such as contaminants from the adjacent Navy Outlying Landing Field, As outlined, however, in Sections D.5a and G,2c, potential contaminant . prbblems have now surfaced with regard to clapper rails.

H. PUBLIC USE

1. General

Tijuana Slough receives at least 35,000 visits annually. Due to the Refuge's urban setting and mild climate, public use levels are fairly constant throughout the year. The visitor center, when fully operative, will result in an upsurge of public use activities; however, potential impacts to Refuge resources that might be caused by this increased use of the area will be partially mitigated by a well planned trail system, active visitor education programs, and intensified law enforcement efforts.

Refuge staff actively promote environmental awareness in the community by emphasizing visitor contact; disseminating interpretive literature; generating newspaper articles; and, time permitting, providing formal tours and presentations to school groups, organizations/clubs, political officials, and other interested parties.

San Diego and Imperial Beach newspapers produced numerous articles during the period covering Refuge related subjects, including: the Refuge's water quality (wastewater) problem. Navy Outlying Landing Field helicopter activity, illegal alien movement through the area, mosquito control efforts, habitat development activities, the status of least terns and other endangered species, the San Diego Bay NWR project, illegal paramilitary operations, and the proposed third border crossing. Refuge staff were usually involved via interviews.

Local TV stations interviewed Refuge staff during the year. Examples include:

In September, Weitzel participated in a KNSD Channel 39 environmental series being run in anticipation of Earth Day.

Weitzel discussed the proposed third border crossing on XETV Channel 12 (Tijuana, Mexico) in January.

2. Outdoor Classrooms - Students

The CDPR environmental education specialist conducts classes within the Refuge throughout the year. Local elementary/high school groups participate in these programs. In addition, Boy/Cub Scout clubs, docents from the Chula Vista Nature Interpretive Center, and undergraduate/graduate students from San Diego State University, were among the numerous groups that incorporated Refuge visits into their classroom activities during 1990. Refuge staff assisted with many of these efforts. These efforts will greatly intensify when the visitor center's educational program becomes fully functional.

3. Outdoor Classrooms - Teachers

The Research Reserve's Education Coordinator provides teacher training seminars on an infrequent basis during the year. Participants include e4i>eators from throughout the various school systems in San Diego County.

4. Interpretive Foot Trails

As discussed in Section D.4, permitting efforts relative to the proposed trail system continued throughout the period. Wording for regulatory and interpretive signage was proposed.

A well maintained trail system will facilitate control of public use activities and direct visitor use away from sensitive resources.

6. Interpretive Exhibits/Demonstrations

Visitor Center exhibitry planning continued throughout the period. Dick Kuehner, Regional Office Public Use Specialist assumed the role as the Service's representative on the exhibit committee. An interpretive prospectus, for fundraising purposes, was developed by the Regional Office in May.

In July, the Refuge sponsored a booth at the third annual "Color of Conservation Fair" at the San Diego Wild Animal Park. The Refuge exhibit, manned by staff and volunteers, included videos, brochures, the mobile refuge system exhibit and a display of confiscated wildlife artifacts (e.g. marine turtle shells, spotted cat pelts). Via this action, hundreds of visitors were exposed to Tijuana Estuary Management issues and the Service/Refuge system in general. Refuge participation in this event is anticipated annually. 32

The Refuge booth at this year's "Conservation Fair" at the San Diego Wild Animal Park. LF-7/90

7, Other Interpretive Programs

The need for bilingual (Spanish/English) signage and interpretive leaflets is recognized. Ongoing efforts include translating educational posters, questionnaires and other material to Spanish; most translations are accomplished by Manager Weitzel,

In September, Manager Weitzel participated in a rainforest conservation symposium, sponsored by the Smithsonian, and held at the San Diego Museum of Natural History. The last day of the event, 07 September, included a tour of the Refuge involving participants from Colombia, Brazil, Mexico, Ecuador and Bolivia.

9. Fishing

Fishing, including clamming and shrimping, is restricted to the intertidal beach zone and mouth of the Tijuana River. Due to active law enforcement patrols and the public's perception of a deteriorated water quality situation (from untreated wastewater), illegal fishing efforts are infrequent. Ghost shrimping within closed areas is the most commonly observed violation. 33

11. Wildlife Observation

With over 300 species frequenting the Refuge, birding opportunities are considered excellent. 'Examples of groups participating this year in organized bird watching trips: San Diego Field Ornithologists, local chapters of the Audubon Society and the Sierra Club, Imperial Beach Quilters, Scripps Aquarium, the San Diego National History Museum, numerous elementary/high school/college classes, the Nature Company and Zoological Society of San Diego and classes organized by San Diego County Parks Department.

Btffh SWIA and CDPR offer guided tours on the first and second Saturday of each month. These popular tours, initiated in 1984, average 30+ participants per session.-

15. Off-Road Vehicling

Non-Service traffic is prohibited; however, access by U.S. Border Patrol and County of San Diego Mosquito Abatement vehicles is authorized under special circumstances. All vehicles must stay on established maintenance roads.

An ongoing issue with Border Patrol, relative to agents driving into restricted areas, was addressed throughout the year via telephone conversations and on-site meetings between that agency and Research Reserve/Refuge staff. The frequency of the infractions seems to be decreasing.

This wayward driver ended up in the Refuge's wetland zone. RR-8/90 3A

16. Other Non-Wildlife Oriented Recreation

Surfing and swimming in the beach zone are avidly practiced throughout the year. Bike riding, jogging and hiking are common recreational pursuits in the upland areas; these activities are restricted to established roads.

A _+ one acre site, located immediately adjacent to 5th Street housing, is used by City of Imperial Beach Little League teams. Under an annual Special Use Permit, League teams have utilized this area for many years; however, no pe^rmanent structures are allowed on the site.

17. Law Enforcement

The presence of on-site staff has alleviated the intensity of illegal actions such as off road vehicle use of beach/dune habitat, dumping/littering, and trespass; however, because of the Refuge's urban position, these activities will probably always occur to some degree. Law enforcement efforts at this stage in the development of the Refuge emphasize sensitizing visitors to the value of the area's resources and infoming them of public use regulations. Citations, however, are issued when necessary.

Impacts to marsh vegetation and least tern nesting efforts result from illegal alien foot traffic from Mexico. The U.S. Border Patrol apprehends 1500 or more illegals on the Refuge every month; hundreds more pass through the area, escaping arrest. I1legal traffic is increasing exponentially as more Mexicans are forced to seek work in the U.S. due to the continued devaluation of the Mexican peso.

Northbound illegal immigrants from Mexico about to negotiate the mouth of the Tijuana River. PR-3/90 35

Some of these aliens are in the business of transporting illicit drugs, with most of this narcotic traffic accomplished at night. According to Border Patrol, the Refuge is fast becoming a well established drug route. Enforcement efforts within the Refuge, relative to these alien/drug activities, are left to the Border Patrol, Throughout the year, an increase in drug related violence along the Research Reserve/international border interface was noted. Luckily, to date, personnel affiliated with the Research Reserve/Refuge have not been involved in such incidents.

. Manager Weitzel provides formal orientation to Refuge law enforcement policy, as heeded, to newly arrived CDPR rangers.

During the period, the following citations were issued:

—February - use of air gun (BB gun); $150,00

—April - Disturbing plants and animals; $150.00

—June - Fishing in an area closed to fishing; $100.00

—August - Fishing in an area closed to fishing; $100,00

—August - Operating a motor vehicle off road, through the wetland; $75.00

—September - Fishing in an area closed to fishing; $100.00

—September - Fishing in an area closed to fishing; $100.00

—October - Fishing in an area closed to fishing; $100,00

—October - Fishing without a license; $100.00

—October - Fishing without a license; $100.00

—October - Fishing in an area closed to fishing; $100.00

—November - Disposal of waste into the Refuge; $150.00

—November - Disturbing plants and animals; $150,00

Other noteworthy law enforcement actions during the period included:

—During the year, a human body, on two separate occasions, was discovered on the Refuge. One Hispanic male, an apparent drowning victim who had been in the water for at least eight days, was observed in May. The second individual, another apparent drowning, was recovered in late August,

—Various Service/CDPR law enforcement coordination meetings were accomplished during 1990. It was finally determined that State Park Rangers can enforce California game codes and some municipal ordinances on Refuge property. Up to this point, uncertainty relative to the Rangers' authority on the Refuge had precluded establishing an efficient cooperative enforceipent program. 36

—A horse was abandoned by an illegal alien on the north part of the Refuge in August. A local stable owner recovered the animal.

—Assistant Ryno met with LNFO and County Park personnel to review illegal clearing of riparian habitat within the Tijuana River Valley by a local sand and gravel operation.

—Manager Weitzel and Biologist McGill were interviewed in January for the Fox TV series, "The Reporters", relative to illegal paramilitary activities along tfife international border.

I. EQUIPMENT AND FACILITIES

1, New Construction

As indicated in Section D.6, Visitor Center landscaping and related efforts were initiated during the year. Landscaping will be completed in 1991.

Early in the year, a number of small construction projects related to the Visitor Center were completed by the contractor.

2. Rehabilitation

In August Salton Sea NWR maintenance worker M. Orozco and the YCC crew replaced the highly oxidized entry gate at Seacoast Drive.

4. Equipment Utilization and Replacement

Refuge vehicles are leased through GSA Fleet Management. Currently, the Refuge maintains a Ford Ranger pickup, a Chevrolet S-10 4x4 and a compact Chevrolet Sedan (acquired in June).

In September, Refuge staff secured office furniture from the recently closed Bureau of Census office in Irvine, California. Items included desks, chairs, partitions, calculators, and coat racks.

5. Communication Systems

A radio base station and two mobile (car) units were purchased from Motorola and installed in August.

A Canon Faxphone 15CD machine was purchased by CDPR in November. The Service funded line installation.

6. Computer Systems

The long awaited NEC 260 laptop computer and portable printer arrived in January. The unit had been ordered approximately 10 months earlier. 37

8. Other

Approximately 120 yards of six foot chain link fence, plus steel posts, was donated to the Refuge hy the Vista, California Boys and Girls Club in January.

The Refuges previous office, located in City of Imperial Beach's Public Works Building was painted/cleaned and officially "returned" to the City in January.

J. OTHER ITEMS J- 3. 'Items of Interest

Training/Conferences/Workshops, etc. completed during the period.

Weitzel: Pacific Coast Clapper Rail Workshop; Sacramento, CA; 16 February

Law Enforcement Refresher; Sacramento, CA; 5-9 March

California/Nevada Project Leaders Meeting; Sacramento, CA; 26-28 March

"Study, Management and Conservation of Migratory Shorebirds and Aquatic Environments"; Ensenada, Mexico; 16 April; Presentation made.

Beneficial Dredging in the Western U.S.; Corps of Engineers sponsored; San Diego, CA; 23-25 May

Supervision and Group Performance; 0PM; San Diego, CA; 4-8 June

San Diego Bay Symposium; San Diego, CA; 15 June

Pro Esteros 1st Annual Meeting; Tijuana Slough NWR, Imperial Beach, CA; 16 June; Presentation made.

Firearm Requalification; Lake Parrish, CA; 30 August

National Estuarine Research Reserve Manager's Workshop; Tijuana Slough NWR, Imperial Beach, CA; 14-19 October; Presentation made.

Management of Protected Areas; University of Baja California, Ensenada, Mexico; Seminar held at Tijuana Slough NWR, Imperial Beach, CA; 30 November; Presentation made.

Ryno:

Basic Law Enforcement; FLETC, Glynco, GA; 27 February - 12 May

Firearms Requalification; Lake Parrish, CA; 30 August

Public Use Workshop; Malhuer NWR, Princeton, OR; 22-26 October

Weitzel was presented with a Special Achievement Award period. Weitzel is affiliated with the following professional organizations:

Society for Ecological Restoration Society for Caribbean Ornithology San Diego Peace Corps Association National Military Fish and Wildlife Association

Ryno belongs to:

The Wildlife Society

4. Credits

Written and edited by Marc Weitzel; Ron Ryno assisted with Section G.2c. Typing/assembly by Shelly Hunter. Photos are credited by initials: Marc Weitzel - MW; Ron Ryno - RR; Mike McGill - MM; Linda Foster - LF; Phill Roullard - PR.

SWEETWATER MARSH NATIONAL WILDLIFE REFUGE

CHULA VISTA, CALIFORNIA

, ANNUAL NARRATIVE REPORT

CALENDAR YEAR 1990

U.S. Department of the Interior Fish and Wildlife Service NATIONAL WILDLIFE REFUGE SYSTEM REVIEW AND APPROVAL

SWEETWATER MARSH NATIONAL WILDLIFE REFUGE

CHULA VISTA, CALIFORNIA

ANNUAL NARRATIVE REPORT

CALENDAR YEAR 1990

Refuge Manager Date Refuge Supervisor Review

Regional Office Approval Date INTRODUCTION

Sweetwater Marsh NWR, sited in southern San Diego County, California, was incorporated into the National Wildlife Refuge System on August 12, 1988. The 315.8 acre Refuge, the product of years of controversial litigation between the City of Chula Vista and the Sierra Club and League for Coastal Protection, consists of land transferred from the State of California and the Santa Fe Land Improvement Company.

The Refuge encompasses the largest emergent wetland zone remaining in San Diego Bay, and supports approximately 200 species of birds, including the erJdangered light-footed clapper rail and California least tern. A substantial population of the state endangered/federal candidate Belding's savannah sparrow thrives in the pickleweed dominated mid-upper salt marsh. Remnant numbers of an endangered annual estuarine plant, the salt-marsh bird's beak, are located in upper marsh habitat. One upland transition plant, Frankenia palmeri. a colony of which is sited within the Refuge's Gunpowder Point area, is not known to occur anywhere else in the U.S.

The City of Chula Vista operates a multi-million dollar nature interpretive center sited on a court granted Refuge easement.

Currently, priority Refuge management continues to be directed at establishing and enhancing working relationships with the City of Chula Vista and other concerned parties; overseeing the design and implementation of numerous long range mitigation programs required by a U.S. District Court Settlement; and developing routine refuge programs, such as law enforcement, resource monitoring, contaminant assessment, and educational activities.

Sweetwater Marsh NWR - view looking east. WH-1/88 SWEETWATER MARSH NATIONAL WILDLIFE REFUGE UNITED STATES SAN DIEGO COUNTY. CAUFORNIA UNITED STATES DEPARTMENT Of THE INTERlOH FISH AND WILDLIFE SERVICE R 2 W

m-or R 2 W 117*0«' COMPILED IN REALTY FROM SAN BERNARDINO MERIDIAN SURVEYS BY FW3. USQS. BLM MEAN O 1000 2000 3000 4000 FEET jt DECLINATION I 1989 0 600 1000 METERS PORTLAND. OREGON DECEMBER 198S REV,: 1R CALIF 1076 402 'PAGE

INTRODUCTION

TABLE OF CONTENTS i

A. HIGHLIGHTS 1

B. CLIMATIC CONDITIONS 1

C. LAND ACQUISITION fT Fee Title 1 2. Easements 1 3. Other NTR

D. PLANNING

1. Master Plan NTR 2. Management Plan 2 3. Public Participation 2 4. Compliance with Environmental and Cultural Resource Mandates .... 2 5. Research and Investigations 4 6. Other 4

E. ADMINISTRATION

1. Personnel 5 2. Youth Program 5 3. Other Manpower Programs 7 4. Volunteer Program 8 5. Funding 8 6. Safety 9 7. Technical Assistance 9 8. Other 9

F. HABITAT MANAGEMENT

1. General 10 2. Wetlands 11 3. Forests NTR 4. Croplands NTR 5. Grasslands NTR 6. Other Habitats 14 7. Grazing NTR 8. Haying NTR 9. Fire Management 14 10. Pest Control 15 11. Water Rights NTR 12. Wilderness and Special Areas NTR 13. WPA Easement Monitoring NTR

i G. WILDLIFE 'Page

1. Wildlife Diversity 15 2. Endangered and/or Threatened Species 16 3. Waterfowl 18 4. Marsh and Water Birds 19 5. Shorebirds, Gulls, Terns and Allied Species 19 6. Raptors 19 7. Other Migratory Birds 19 8. Game Mammals NTR 9. Marine Mammals NTR . lOX Other Resident Wildlife 19 iTT Fisheries Resources 20 12. Wildlife Propagation and Stocking NTR 13. Surplus Animal Disposal NTR 14. Scientific Collections 20 15. Animal Control 20 16. Marking and Banding 20 17. Disease Prevention and Control NTR

H. PUBLIC USE

1. General 21 2. Outdoor Classrooms - Students 22 3. Outdoor Classrooms - Teachers NTR 4. Interpretive Foot Trails 22 5. Interpretive Tour Routes ' NTR 6. Interpretive Exhibits/Demonstrations NTR 7. Other Interpretive Programs 22 8. Hunting NTR 9. Fishing NTR 10. Trapping NTR 11. Wildlife Observation 24 12. Other Wildlife Oriented Recreation NTR 13. Camping NTR 14. Picnicking NTR 15. Off-Road Vehicling NTR 16. Other Non-Wildlife Oriented Recreation NTR 17. Law Enforcement 24 18. Cooperating Associations NTR 19. Concessions NTR

I. EQUIPMENT AND FACILITIES

1. New Construction 25 2. Rehabilitation 25 3. Major Maintenance NTR 4. Equipment Utilization and Replacement NTR 5. Communications Systems NTR 6. Computer Systems NTR 7. Energy Conservation NTR 8. Other NTR J. OTHER ITEMS "Page

1. Cooperative Programs NTR 2. Other Economic Uses NTR 3. Items of Interest NTR 4. Credits 25

K. FEEDBACK NTR

I. INFORMATION PACKET (inside back cover)

iii 1.

A. HIGHLIGHTS r

Numerous mitigation projects initiated during the period (see Section D.2, D.4, D.6, F.2, F.6, F.10).

The YCC crew installed"vehicle barricade protecting F-G Marsh (see Section F.2).

The Director of Chula Vista's Nature Interpretive Center, sited on a refuge easement is the subject of a high profile law enforcement action (see Section H.17).

^ . B. CLIMATIC CONDITIONS

See Tijuana Slough NWR narrative.

C. LAND ACQUISITION

I. Fee Title

Resulting from extensive litigation in U.S. District Court between the City of Chula Vista and the Sierra Club/League for Coastal Protection, the Sweetwater Marsh NWR (Refuge) was established upon close of escrow on August 12, 1988, Of the 315.8 acres deeded to the Fish and Wildlife Service (Service), 35.5 acres were transferred from the State of California and 280.3 acres from the Santa Fe Land Improvement Company (SFLIC). Santa Fe, by transferring this acreage to the federal government, has now reserved the legal right to proceed with commercial/residential development within their midbayfront property sited immediately adjacent to the Refuge (see section D.6).

As the midbayfront is developed, it is possible that a few acres may be added to the Refuge as mitigation for impacts associated with these actions. Another +_ 25.0 acres may be secured as mitigation from the United Port District of San Diego at some point in the future. The close proximity of urbanization, however will prevent any other expansion.

2. Easements

The U.S. District Court "stipulated settlement" (Settlement) granted the City of Chula Vista an easement to 3.4 acres of Refuge uplands, specifically within Gunpowder Point. Sited within this easement is the City-owned and operated $2,3 million Nature Interpretive Center (NIC), The City has been granted this easement in perpetuity as long as NIC is operated as a nature center; any deviation (e.g. converting NIC to City office space) will void the easement and building ownership will revert to the Service. The City of Chula Vista also maintains a court issued license to use and maintain the Refuge's south levee road (the only access route to NIC).

In addition, the Settlement designated +_ 92 acres of Refuge as "lease hold acreage", or mitigation bank acres/credits, A private sector developer, for example, can purchase said mitigation credits for enhancement purposes. The developer may elect to perform the actual restoration, or provide the Refuge with an equivalent amount of funds. The Refuge gives the final "yea or nay" on a proposed project. Shortly after the Refuge was established in August 2.

1988, Signal Landmark Corp./Coronado, CA, purchased, for $450,000.00, t^n acres of lease hold acreage for the purpose of enhancing California least tern nesting habitat. Of this purchase fee, $48,500.00 went to the Service for Refuge operations; under the terms of the Settlement, the balance was available to the previous landowner. The Service's portion of this transaction, and funds 'from any subsequent sale will be held by the Fish and Wildlife Foundation, Washington, D.C, until requested by the Refuge. This funding source covered much of the least tern management work for 1989 and 1990.

On March 3, 1990 a right-of-way easement was granted to the City of Chula Vista for a flowthrough seawater pump station and distribution system. This easement encompasses 0,21 acres. NIC will construct a 400 ft. pump house and two four inch pipelines as funds become available to supply water from the bay to various interpretive exhibits requiring circulating seawater. Currently this water is trucked to a holding tank at NIC. The use of a flowthrough system will both reduce truck traffic on the South Levee Road and improve the quality of exhibits.

D. PLANNING

2. Management Plan

Detailed planning will be accomplished in the future. Currently, however, the Settlement and a detailed Biological Opinion (Opinion) rendered by the Service are employed as interim management documents.

The Opinion pertains to the combined Sweetwater River flood control channel and widening of Interstate Highway 5 (1-5) projects. The Opinion outlines mitigation requirements that must be performed on Refuge lands by the U.S. Army Corps of Engineers (Corps) and/or the California Department of Transportation (Caltrans) due to impacts caused by construction of the flood control channel and widening of 1-5 (both the channel and highway abut the Refuge). The Corps or Caltrans are the overseeing agencies on these construction projects, thus they are responsible for the mitigation provisions of the Opinion. These provisions include saltmarsh restoration, California least tern nest monitoring, predator control, fencing, various research actions, general wetland clean up, and other projects. With the exception of providing assistance with project design, and monitoring implementation, these enhancement efforts will be completed at no cost to the Service.

3. Public Participation

The Bayfront Conservancy Trust (BCT) was established to address operational concerns of NIC. The BCT meets every one to one and a half months. Current voting members include: the Mayors of Chula Vista and National City, the San Diego Unified Port District, the Sierra Club, the San Diego County Board of Supervisors, and California Department of Fish and Game; the Refuge is an ex- official member.

4. Compliance with Environmental and Cultural Resource Mandates

The Refuge has the on-going responsibility to ensure that all mitigation programs and other provisions required by the Settlement, and/or Opinion are 3 implemented (see Section C.2 and D.2). Many of the programs take place within the Refuge, and most if not all others adjoin the Refuge. The following table is a partial list of coordination meetings attended by Refuge staff to meet this responsibility.

DATE ORGANIZATIONS REPRESENTED PRIMARY SUBJECT (in addition to the Refuge)

-dune 12 Corps, Chula Vista, Salton Sea Corps' mitigation, NWR, USFWS Enhancement Office especially (Enhancement) recreation facilities

June 19 Corps, Chula Vista, NIC Corps' mitigation responsibilities

August 21 Enhancement, Corps, NIC Corps' mitigation responsibilities

October 18 Caltrans, Enhancement, San Diego Caltrans State University mitigation progress

November 7 & 14 Corps, Enhancement Impacts of work on the Flood Control Channel

November 29 Corps, Enhancement Impacts of work on the Flood Control Channel

December 5 Caltrans Preparation of D St. Fill for terns; Predator control. December 10 Enhancement, Corps Minimizing impacts of Flood Control Channel on marsh vegetation

December 18 Enhancement, Corps Minimizing impacts of Flood Control Channel on marsh vegetation

Meetings attended by Refuge staff to coordinate implementation of the Settlement and Opinion. 5. Research and Investigations

Refuge Personnel

A contaminant assessment program was initiated in 1989. Again this year the same seven sites were sampled. The Sweetwater Marsh program is patterned after the Tijuana Slough NWR contaminant study (see Tijuana Slough narrative, section D.5), Steve Goodbred of the Laguna Niguel Field Office coordinated the study. He received assistance in collecting samples from Wildlife Biblogist McGill and the YCC enrollees.

Non-Refuge Personnel

a. Sweetwater River wetlands complex: functional assessment of constructed wetlands 11631-SW-02

Pacific Estuarine Research Laboratory

An ongoing effort, with the overall objective of assessing how well man-made wetlands replicate the functional values of the natural wetlands remaining in the Sweetwater Marsh complex. For example, how long does it take artificially created wetlands to develop a food chain support system? Initial results indicate the created wetland soils are, at least for a number of years, lower in organic matter and nutrients, the cordgrass has less biomass and less foliar nitrogen and epibeilthic invertebrates are less than half as abundant when compared to nearby natural marshes. Results of the project could greatly impact how regulatory agencies develop mitigation programs.

b. Assessment of habitat characteristics and shorebird use-patterns in the Sweetwater River Wetlands Complex 11631-SW-05

P. Ashfield, San Diego State University

This study, initiated in 1989, compares shorebird use of various habitats. In particular, it compares man-made habitats with natural ones. This information could improve mitigation projects for creation of shorebird habitat,

c. Growing Frankenia palmeri in a controlled growth chamber 1163l-SW-07

C. Davis, Bonita Vista High School

The only known colony of Frankenia palmeri in the U.S. is on Gunpowder Point. Plans call for using cuttings from these plants in revegetation projects at the Refuge. This study is designed to compare the relative effectiveness of growing cuttings outdoors versus in controlled growth chambers.

6. Other

On-going assistance was provided to adjacent landowner/developer Chula Vista Investors (CVI) in addressing environmental concerns relative to their proposed $500 million "Bayfront" project. Said project, which will abut the Refuge, may include: retail shops; five hotels; a 1,550 unit apartment complex; conference center/theater; athletic facilities, including a tennis court; and miscellaneous offices supporting a resident population of over 3,000 people. So far, "CVI has been very receptive to Refuge input and incorporated much of it into the EIS currently being written. Although the "Bayfront" project accounts for most of the land adjacent to the Refuge not included in the I-5/Flood Control Channel construction, refuge staff coordinated with other organizations planning development bordering the Refuge that could negatively impact sensitive resources. The two most significant Is were the Rohr Corporation office project and the San Diego Bay Route

The Rohr Corporation formalized plans to construct a large office building and parking lot along the east side of the F-G Marsh unit of the Refuge. Through meetings with refuge staff and Martin Kenney of the Laguna Niguel Enhancement Office, Rohr's environmental consultant has developed a plan that will not only mitigate much of the impact of this project on the F-G Marsh, but will actually enhance the area with the creation of a seasonal freshwater wetland.

For several years now, the San Diego Association of Governments has been adding to and/or upgrading existing segments of the San Diego Bay Route Bikeway, a bicycle trail that will eventually form a loop completely around the Bay. During this period, the Bay Route Bikeway Committee invited Assistant Ryno to be a member of their "Technical Committee". Originally, plans called for the Bikeway to cut through the Refuge from the north to the south with one or two east-west spurs. This would have clearly had a negative impact on refuge resources, especially endangered species. Eventually a compromise was reached to place the Bikeway on the eastern boundary along the berm of 1-5 and eliminate any east-west spurs into the Refuge, An added benefit of Service representation on this committee was that the final portion of the Bikeway, intended to bisect the south end of San Diego Bay, was re­ routed to avoid areas used by large numbers of wintering migratory birds as well as important nesting areas for several endangered and sensitive species.

E. ADMINISTRATION

1. Personnel

The Refuge is administered by Tijuana Slough NWR personnel. Staffing for the period involved:

Marc M. Weitzel - Primary Assistant Refuge Manager, GS-485-11 PFT: EOD 1/87 Ronnie L. Ryno - Assistant Refuge Manager, GS-485-09 PFT: EOD 8/89 Michael L. McGill - Wildlife Biologist, GS-486-07 TFT: EOD 6/90

2. Youth Programs

This was the second year for a Youth Conservation Corps (YCC) program at the Refuge. YCC projects ran from June 25 to August 17, and involved the following personnel: 6

Linda Foster - Social Services Assistant, GS-186-05 Jack S• Memea Jennifer B. Melendez Brandon J. Moody'- Youth Leader Librado 0. Orduno

The YCC crew completed a number of significant projects at the Refuge. The construction of a vehicle barricade along F Street was especially beneficial. The city of Chula Vista supplied the materials, Marcos Orozco, maintenance . worker from Salton Sea NWR, provided expertise, guidance and tools and the YCC creln supplied the blood, sweat and tears (luckily blood was kept to only a drop or two). This area along the F-G Marsh has always been a major problem site, attracting people looking for a place to collect bait, drain waste oil, dump trash, and practice off-road vehicle maneuvers, BMX races and more. As a result of the YCC's actions these activities have been all but eliminated, especially the more serious ones. Additionally, the YCC crew assisted with contaminant sampling, filled a 40 yd3 dumpster with all kinds of things that do not belong around a marsh, and removed exotic vegetation.

Vehicle barricade erected by YCC to keep people, vehicles and trash out of F-G Marsh. Left to right are: L. Orduno, J. Memea and B. Moody. LF-7/90 YCC crew fills a durnpster with trash and exotic vegetation. Left to right are: L. Orduno, J. Melendez, B. Moody and J. Memea. LF-7/90

3. Other Manpower Programs

While reviewing Caltrans' plans for construction and restoration along the southeastern portion of Sweetwater Marsh, it was noticed that an area of fill consisting of an elevated road bed running through the Refuge had not been listed among the areas to be restored in the Settlement. Caltrans agreed to remove the road and haul off the material at no expense to the Service. Not only did this create an additional one half acre of freshwater marsh, but it greatly improved the health and vigor to the adjoining marsh. As this is the only major fresh water source within the Refuge, it has increased wildlife diversity. In addition, light-footed clapper rails have been noted in this area including an adult with a chick. Since the removal of the levee, clapper rails have been noted here more than any other site on the Refuge. Caltrans heavy equipment removed an old road bed from the fresh water marsh at the south end of Connector Marsh. RR-2/90

4. Volunteer Program

The Refuge relied heavily on NIC's volunteer system. Again this year dozens of individuals donated time to remove tons of debris from the area. From September through April, NIC volunteers conducted bi-monthly bird walks and bay walks. These walks not only provide valuable data to refuge staff concerning wildlife activity, but they are extremely popular interpretive programs. Other volunteer efforts include a long term program to remove exotic vegetation and re-establish native plants, as well as training future docents that will conduct educational programs at both Sweetwater Marsh and Tijuana Slough NWR's. Official Service volunteers assisted in both wildlife inventory work and in providing professional quality photography.

5, Funding

The Refuge does not receive direct Service funding; refer to the Salton Sea NWR narrative for details.

As outlined in section C.2, mitigation funds generated from the sale of lease hold acreage are available for operational concerns. The Refuge's mitigation account currently sets at $26,132 following an expenditure of approximately $7,400 during 1990 for endangered species work, primarily directed towards California least terns. A substantial amount of additional funds may become available in future years. 9

6. Safety

No accidents (to personnel or equipment) occurred during the period.

7. Technical Assistance

To insure compliance with the Opinion and Settlement as well as Refuge policy and resource needs, frequent meetings have been held with Caltrans and the Corps. Planning meetings were held prior to the renewal of construction in September (see Section D.4).

New proposals to develop both land and water near the Refuge continue to arise, each with potential impacts to the Refuge. In addition to CVI (see Sec. D.6) other private developers received Refuge staff assistance during the period (see Section D.4). Staff attended a number of meetings concerning proposals ranging from parking lots to marinas around the Refuge. For example, in August ARM Ryno met with Martin Kenney of the Laguna Niguel Enhancement Office and representatives of California Fish and Game, National Marine Fisheries Service, several environmental consultants and developers to evaluate a boat yard proposal for the southwest corner of 24th Street across from the California least tern colony on the D Street fill. In November ARM Ryno met with California Fish and Game, the Mayor of National City and more environmental consultants concerning a used car reception depot and railroad siding adjoining Paradise Marsh.

8. Other

The following special use permits were issued during the period:

April - Six month permit to E. Copper and assistants to monitor CA least tern nesting,

June - Three month permit for a marine science course of the Sweetwater Union High School District.

November - Eight month permit to NIC to conduct environmental education activities.

December - One day permit to Jennifer Price of Southwestern College to clean up trash on D Street Fill.

The annual station inspection occurred on February 8 and 9 with Associate Manager Bob Fields. Included was a meeting with Caltrans biologist John Reiger to discuss Settlement/Opinion projects.

During June, Bill Meek, appraiser from the Regional Office visited the Refuge to update the land values for revenue sharing purposes. 10

F. HABITAT MANAGEMENT

1. General

The Refuge supports the following habitat types: a) Upland Zones. Includes historically disturbed sites such as Gunpowder Point, which contains a remnant coastal sage scrub community; and the D Street Fill, an area created by dredge spoil in the ISSO's. Until 1989, D Street Fi^l was dominated by exotic flora, such as pampas grass.

As part of the Settlement, Caltrans cleared nearly all of the exotic vegetation. This action has three primary benefits. It creates ideal open habitat for nesting California least terns, promotes compatible native species and it removes almost all cover for land predators such as skunks and feral cats.

Caltrans used heavy equipment to dig up pampas grass and other exotic vegetation, then buried the material to create open California least tern nesting habitat. MW-3/90 b) Upland/Wetland Transitions. An area indicated by both saltmarsh and coastal sage scrub flora, including saltgrass (Distichlis spicata) and alkali heath (Frankenia grandifolia)« A rare plant, Yerba Reuma (Frankenia palmeri), is found within the zone. The Refuge colony of F., palmeri represents the only known occurrence of this plant in the U.S.; the species is common at certain localities in Mexico. 11 c) Intertidal Mud Flats. Areas exposed at low tide that provide extensive forage and loafing opportunities for shorebirds. d) Saltmarsh, This tidally influenced habitat is typically defined as low, middle, or high marsh zones (see Tijuana Slough NWR narrative, section F.lg). All characteristic southern California saltmarsh flora can be encountered within the Refuge including a small remnant population of the endangered saltmarsh bird's beak (Cordylanthus maritimus). Saltmarsh areas include the Vener Pond and the E, F-G, Sweetwater, Paradise and Connector Marshes. Together they comprise the largest emergent wetland remaining on San Diego B^y; Extensive eelgrass (Zostera marina) beds are found off the Refuge/San Diego Bay interface, particularly adjacent to Gunpowder Point.

2. Wetlands

Settlement mitigation programs include placing additional culverts on the NIC access road to increase tidal infusion into Vener Pond, creation of a 17 acre saltmarsh at the eastern tip of the D Street Fill, tidal flushing enhancement efforts at F-G Marsh and as outlined in section D,5, wetland research projects. Said research activities are in progress; the habitat enhancement efforts are under way also. The Refuge is assisting other entities in defining details for all mitigation projects (see Section D.6).

One such enhancement effort, the 17 acre wetland within the D Street Fill, was initiated in 1989. The project was completed in March 1990 and opened to tidal action. Almost overnight this 17 acre mudflat (ultimately to be low marsh) became a significant shorebird, tern and osprey foraging area, and the newly cleared D Street Fill uplands received heavy use as a shorebird roost. Research has shown that lack of organic material greatly slows revegetation. Therefore, an experiment is under way to test the effect of several soil amendments. Results will determine what will be added to the soil during revegetation next year. In keeping with the Settlement, Caltrans resumed construction along 1-5 in early September. Work during late 1990 included removal of fill that in some cases pjredated freeway construction work and in other cases was only temporarily needed for earlier phases of the project. 12

Seventeen acres of the D Street Fill were removed to create marsh as part of the Settlement. Although it may look barren before it is revegetated, this site has high value as a foraging area for shorebirds, terns and ospreys, RR-4/90

Illegal vehicle trespass has continually impacted Refuge wetlands. During this period, two major projects were completed to reduce this problem. The YCC installed a vehicle barricade along F-G Marsh (see Section F..2). The second project came about through the cooperation of San Diego Gas and Electric Company (SDG&E).

The Refuge is bisected from north to south by a high power transmission line and accompanying oil pipeline, both within a narrow strip of SDG&E property. An old access road enters the marsh along the south end of this area and creates easy access for vehicles into the adjoining marsh. Biologist McGill was able to convince SDG&E to install a locked gate across this road. He then enlisted the YCC crew to extend a fence out from either side of the new gate. This has greatly reduced vehicle access and accompanying impacts to the marsh in the southern portion of Sweetwater Marsh. Marsh damage like this was common place due to uncontrollable vehicle access along SDG&E's access road. RR-6/90 14

This gate and a few strands of wire have all but eliminated most marsh damage in this area» RR-7/90

6. Other Habitats

Each year from September through March construction continues along 1-5 to the east and the Flood Control Channel to the north. Biologist McGill has worked hard at keeping up on where new access roads are created and old fences are removed. It seems that as soon as he fences and signs one spot, a new access point appears. This will continue te impact Refuge resources from illegal dumping, off-road travel and general trespass until all projects are finished, the legal boundary is posted and all gates locked.

On a more positive note, in April Caltrans completed the D Street Fill mitigation fencing along the eastern perimeter. This 1160 linear foot fence cost Caltrans approximately $32,000 plus $6,300 for signage. It is six feet high with three strands of barbed wire on top and extends 18 inches under ground. Not only does this fence keep most people out, but when two men were cited for trespass on D Street Fill, their explanation that they did not know they were in a closed area fell on deaf ears when the Magistrate saw a picture of the fence and signs.

9. Fire Management

Burn potential is considered minimal. However, because the Refuge essentially lacks fire management support, contact has been initiated with the Cities of Chula Vista and San Diego relative to developing fire suppression MOUs. 15

Because the Refuge is viewed as any other undeveloped area within their city limits, little interest has been shown by either city.

10. Pest Control

During mosquito high density periods, typically late summer - early fall, the County of San Diego/Vector Control Division uses a larvicide, known as "Golden Bear", within the wetland zone of the Refuge. Golden Bear is a fast dissipating mineral oil that does not impact non-target species.

Effbrts to improve/restore tidal flushing to the saltmarsh has reduced most all the need to treat areas of the Refuge. As a result. Vector Control personnel seldom treat more than a few isolated spots.

The Settlement and Opinion outline predator control measures that must be enacted to protect the California least tern nesting colony on D Street Fill. Under the terms of the Settlement, control actions are funded by the Corps and Caltrans. USDA/APHIS conducted this year's predator control with assistance from Biologist McGill. All predator control efforts, however, are implemented under the auspices of Refuge personnel and control measures are restricted to D Street Fill. Live trapping and removal from the Refuge is prioritized; sacrificing predators is a last resort (see Section G.15).

G. WILDLIFE

1. Wildlife Diversity

Habitat types occurring within the Refuge (see Section F.l) support a rich floral and faunal resource. The most conspicuous wildlife group is resident and migratory birds. Approximately 200 species in this category have been seen on the Refuge; five of which are listed as federal and/or state endangered. The saltmarsh zone exhibits the largest number of bird species. This same zone also supports a substantial population of various invertebrates, including insects and-in particular benthic organisms.

The Refuge's upland zones are at this stage in dire need of restoration, most having been subjected to years of degradation via numerous uncontrolled public use activities. The past two years' clean up efforts signify the first step in enhancing the wildlife value of these areas. 16

2. Endangered and/or Threatened Species

= ENDANGERED AND/OR THREATENED STATUS-

California Brown Pelican FE, SE Peregrine Falcon FE, SE L-i^ht-footed Clapper Rail FE, SE California Least Tern FE, SE Beldirig's Savannah Sparrow SE Saltmarsh Bird's-beak FE,SE

-FE = Federal Endangered SE = State Endangered

a) California Brown Pelican

Brown pelicans can be encountered in San Diego County year-round but are most abundant summer through fall and scarce in late winter. Pelicans forage along major waterways on the Refuge and occasionally roost at Gunpowder Point and D Street Fill near the shoreline.

b) Peregrine Falcon

This endangered falcon winters on San Diego Bay and one or two birds have hunted around the Refuge on an irregular basis from September to December. A pair nested again this year on the Coronado Bridge only 3 miles north of the Refuge and occasionally foraged during summer on the Refuge.

c) Light-footed Clapper Rail

This subspecies of clapper rail is found only in saltmarshes of Southern California and adjoining Baja California, Mexico with healthy stands of cordgrass. The largest remaining remnant of this habitat on San Diego Bay lies entirely within the Refuge. Unfortunately, due to continued loss of wetlands and increased human activity in and around the area, the number of rails in Paradise Marsh has declined in the last few years. Management of the area is now geared largely to maintaining and, where possible, improving rail habitat that will hopefully reverse this trend.

Clapper rails were censused during March, The table below lists 11 years of data from spring vocalization counts. In 1990 there were two pairs and two individuals. 17

1980 81 82 83 84 85 86 87 88 89 90

Paradise Marsh" 1 2 3 1 1 0 0 0 0 0 0 Sweetwater Marsh 4 5 7 6 14 3 9 5 6 9 6 E Street Marsh 3 1 3 3 2 2 2 0 1 2 0 F&G Street Marsh J- J- 1 1 0 1 0 0 0 0 0 0 TOTAL 8 9 14 10 17 5 11 5 7 11 6

-including Connector Marsh "-not censused

d) California Least Tern

The California least tern is a migratory species, breeding in southern and central California from April through September and wintering in South America. This tern nests in open areas adjoining bays, lagoons or the ocean. They have nested on D Street Fill as indicated below.

1984 1985 1986 1987 1988 1989 1990

Number of Pairs 16-25 43 5-6 26 19 2 0 Number of Nests 41 47 10 32 19 2 0 Fledglings 25 0 7 10+ 0 0 0

In past years, human, avian and mammalian predator activities have significantly reduced nesting success. With the creation of the Refuge, much of the human impact has been eliminated. During 1990 no terns nested on the Refuge. The combination of two consecutive years of failure has caused adults to seek other nesting sites. Despite the absence of any nesting birds, the area was intensely managed for terns in the hopes that pairs of least tern unsuccessful elsewhere in San Diego County would renest at D Street Fill, but this never happened. One to three terns were frequently noted foraging and/or loafing on the Refuge throughout the nesting season.

e) Belding's Savannah Sparrow

Like the light-footed clapper rail, this subspecies is a permanent resident of southern California saltmarshes. The sparrow, however, prefers the middle and upper marsh. It is listed as endangered by the State and is a Federal candidate for listing. Birds nest in all appropriate marshes on the Refuge and forage on nearby uplands and mudflats such as Gunpowder Point and D Street Fill. San Diego State University censused breeding Belding's Savannah Sparrows on March 4, 1989. Their data is presented with that of other workers from past years in the following table. 18

Number of Belding's Savannah Sparrow Breeding Pairs-

II 1977 1986 1989 Paradise Marsh 16 19 9 Sweetwater Marsh 40 118 139-156 E Street Marsh 18 8 4-8

Connector Marsh — — 4-5

-F&G Street Marsh — — 4-5 ^ TOTAL 74 145 160-183

—not censused ^There is some variability in census techniques over time and each census was conducted by different organizations.

f) Saltmarsh Bird's-beak

This endangered annual plant is limited to the high marsh zone, and is only found in a few saltmarshes of southern California and Baja California, Mexico. In an effort to better understand the ecology of this species, San Diego State University is conducting research on the Refuge that will ultimately be used to improve the chances of success when Caltrans, as part of the Settlement, reintroduces saltmarsh bird's-beak to appropriate locations within the newly created marsh at D Street Fill and older man-made areas of Connector Marsh. As part of this regard, seed was placed in Sweetwater Marsh in 1988, but it failed to germinate the following year. Many of these seeds, however, produced plants in 1990. These results, combined with other data show poor germination rates the first year seeds are out, with improved production the following two years.

3. Waterfowl

The Refuge is used by Pacific Flyway"migrants including brant, green-winged teal, northern pintail, cinnamon teal, northern shoveler, American wigeon, mallards and lesser scaup. Peak use is typically December through February. The Refuge is popular with birders, as blue-winged teal, a duck that can be difficult to find in California, regularly winters here.

Peak waterfowl numbers in 1990 are as follows:

Brant - 232 Northern Shoveler - 80 Mallard - 3 Greater Scaup - 10 Gadwall - 2 Lesser Scaup - 183 Northern Pintail - 65 Surf Scotter - 300 Green-winged Teal - 50 Bufflehead - 21 Blue-winged Teal - 14 Ruddy Duck - 10 Cinnamon Teal - 26 Red-breasted Merganser - 5 American Wigeon - 230 Common Merganser - 1 4. Marsh and Water Birds

Eared grebe, great blue heron, great egret and snowy egret are noted with frequency. A reddish egret has wintered on the Refuge for several years. Little blue herons are gradually becoming more common around San Diego Bay and the Refuge is one of the best places to see them. The Vener Pond and Sweetwater Marsh appear to provide favorite loafing/foraging grounds for these species.

. 5ri Shorebirds. Gulls, Terns and Allied Species

Shorebird use is substantial, particularly foraging activities concentrated in mudflat areas exposed by ebb tide. Commonly observed species include: marbled godwit, willet, dowitchers, dunlin, American avocet, black-necked stilt, western gull, Caspian and elegant terns, to name but a few. Peak concentrations occur during the fall and winter months. South San Diego Bay is the only site on the western coast of the United States where royal terns nest. During breeding season, the Refuge and adjoining Bay is a preferred foraging area. The far west end of D Street Fill is becoming increasingly popular with gulls, terns and shorebirds as a protected roost site now that the Refuge has eliminated most human activity in the area.

6. Raptors

Raptor use of the Refuge if fairly substantial. This is due in part to an abundant prey base, in particular the Audubon's cottontail, California ground squirrel and Microtis species. Red-tailed hawks, northern harriers, American kestrels, and black-shouldered kites are most commonly observed. The northern harrier is a known nester. There were several days in January, February, and October when all four species of falcon that occur in southern California could be seen in one day on the Refuge. From two to four ospreys winter on San Diego Bay at any one time. Most or all of those birds spend part of every day roosting and foraging on the Refuge.

7. Other Migratory Birds

The large-billed savannah sparrow (Passerculus sandwichensis rostratus) is a federal candidate species. These birds breed in marshes at the north end of the Gulf of California. In the early 1900's, large-billed savannah sparrows were quite common during winter months throughout coastal San Diego County. However, possibly due to the deterioration of marshes within their breeding range, this bird became increasingly scarce. From the mid-1950's to 1988 there was only one sight record for the county. Then in the fall of 1988 this bird was "rediscovered" at the Refuge, Tijuana Slough NWR and a site between the two. It has continued to winter on the Refuge in small numbers during 1989 and 1990.

10. Other Resident Wildlife

Baseline data on amphibian, reptilian and mammalian resources are minimal. The San Diego coast horned lizard, a federal candidate for the endangered species list, is known to occur in -the upland and marsh-upland transition areas. An amphibian and reptile inventory noted the San Diego alligator lizard, San Diego horned lizard, Great Basin fence lizard, San Diego gopher snake and California king snake.

11. Fisheries Resources

The Refuge supports fish resources characteristic of any southern California estuarine system. Species includes topsmelt, California killifish, long- jawed mudsuckers and gobies. Additional data, including density assessments isl currently being compiled by San Diego State University.

14. Scientific Collections

A one year Special Use Permit was issued in 1989 to NIC for collecting invertebrates used in their live exhibitry. Because the Refuge constitutes the largest remaining emergent wetland on San Diego Bay, many other individuals and agencies have approached the Refuge wishing to collect fish and invertebrates for various reasons. In an effort to protect the resources, these requests are honored only in very select circumstances.

15. Animal Control

As mentioned in Section F.10, the Settlement directs the Corps and Caltrans to fund predator control for the D Street Fill tern colony. This year USDA/APHIS Animal Damage Control (ADC) personnel performed this activity with assistance from Biologist McGill. After this area was cleared of exotic vegetation, the number of mammalian predators was reduced making control efforts more affective. Because common ravens were serious predators of this tern colony for the last two years, it was believed that the presence of a local nesting pair would discourage terns from using the colony. Therefore, these ravens were removed just prior to the arrival of least terns. Despite pressure to the contrary, refuge policy is not to remove any other avian predator until a documented problem exists. Since no terns ever nested during 1990, no other birds were removed. A few skunks and- several feral cats and dogs were removed by ADC.

16. Marking and Banding

Patrice Ashfield, a graduate student from San Diego State University, continued her shorebird study this year on the Refuge (see Section D,5). An important addition in 1990 was the color banding of several birds at the roost site on D Street Fill. Only three red knots, one dowitcher and one western sandpiper were banded, but late in December Ms. Ashfield switched to a much more effective mist netting technique and 1991 should see many more birds banded. 21

H. PUBLIC USE

1. General

Because of the small size and sensitivity of its resources, the Refuge is closed to public use unless the activity is specifically associated with NIC programs, such as bird walks or bug walks. Authorization to access the Refuge is, however, issued to individuals or groups for special events (e.g., Audubon Christmas Bird Counts), ir Tfi^City of Chula Vista officially opened the Nature Interpretive Center on July 4, 1987. Refuge educational objectives are currently addressed by NIC's efforts. - Programs include formal classroom instructions and outdoor activities, serving both elementary/secondary students, and special environmental interest groups. In addition, NIC is open to the general public; visitation through the end of 1990 totaled 233,978. Exhibitry at NIC includes aquaria, terraria, video programs and other displays that explain the resources of the Sweetwater Marsh. Two new exhibits were added this year. The first is the long awaited Burrowing Owl Aviary complete with windowed burrows for a look at the owls when underground. The second is a Bio Scanner, an interactive remote controlled video scanner that produces a close-up detailed view of both aquatic and terrestrial organisms. In addition, a fine natural science bookstore provides visitors with the opportunity to spend money. The Bayfront Conservancy Trust produces a monthly publication, the "Bayfront By-LineM. Manager Weitzel routinely contributes articles to this newsletter.

The Chula Vista Nature Interpretive Center. < 22

2, Outdoor Classrooms - Students

During 1990 approximately 13,850 students received formal classroom instruction at NIC. Subjects emphasized saltmarsh/marine biology and endangered species management.

4. Interpretive Foot Trails

No authorized trails currently exist; however, a loop trail traversing Gugpowder Point and a perimeter path along the midbayfront area are proposed. Both projects will be completed by the Corps, as directed by the Settlement. NIC was issued a SUP to lead tours around Gunpowder Point. Experience gained from these walks may be useful in designing future trails.

7. Other Interpretive Programs

Throughout the year NIC offered a variety of special programs designed to introduce people to the Sweetwater Marsh and the interpretive center that would not normally visit the area. This years special programs included Gyotaku fish printing classes, bat ray kite building, sushi classes and summer day camps. More than 1,300 people attended special programs. Many programs are offered separately for adults or children.

One program of direct benefit to the Refuge was the least tern decoy class. The Service supplied materials for NIC and dozens of participants constructed more than 150 least tern decoys to be placed at D Street Fill and other tern colonies as needed. These decoys have been shown to draw birds to sites where fencing, predator control and other management activities are in place. This activity was covered by a local television station. NIC employees used Materials supplied by the Refuge to make dozens of California least tern decoys. BM-2/90

These decoys were then placed at local tern colonies. RR-5/90 24

11. Wildlife Observation

Currently, authorized wildlife observation is largely limited to overlook facilities associated with NIC. Interest groups including the Audubon Society and San Diego Field Ornithologist Union, are at times granted access for birding purposes within other areas of the Refuge. The Refuge is becoming increasingly popular with birders. This is in part due to the activities at NIC and the fact that status as a National Wildlife Refuge tends to attract people interested in wildlife observation. Another contributing factor is tBat the Refuge continues to be one of the prime spots in San Diego County to o!)serve species popular with birders such as little blue heron, reddish egret, blue-winged teal, prairie and peregrine falcon, merlin, and osprey to name only a few.

17. Law Enforcement

Activities such as off-road vehicling, trespass, dumping/littering, illegal hunting and fishing have historically transpired within the Sweetwater Marsh wetlands. These problems will continue until the adjacent communities of Chula Vista, National City and San Diego become aware of public use regulations and appreciate the importance of protecting the area's resources. Current law enforcement efforts must emphasize education; NIC programs help meet these objectives. Refuge staff makes a point to contact as many people as possible on and around the Refuge, explaining refuge regulations and giving verbal warnings as needed.' These efforts seem to be producing results as compliance has increased in the last year.

Sometimes, however, it is necessary to take a stronger approach. During August two individuals were cited for trespassing on D Street Fill ($50.00 collateral each). One of the men was also cited for fishing without a license ($100,00 collateral).

An unusual, high profile law enforcement case developed this year when two former NIC employees accused the Interpretive Center's Executive Director, Steve Neudecker, of shooting wildlife on the Refuge, All local news papers and the Los Angeles Times ran numerous articles, the City of Chula Vista began their own investigation and ARM Weitzel spent much of his time during April and May on this matter. The USFWS' law enforcement office in Gardena, California was contacted to conduct an investigation for the Service as all Refuge Officers had some degree of professional relationship with the individuals involved in the case. Included in the allegations were that Neudecker kept one or two guns at NIC, he had shot and killed mourning doves that were trapped in the building and that he frequently shot rabbits and squirrels that fed on landscaping plants.

Ultimately Neudecker was cited for two violations of the Migratory Bird Treaty Act (shooting mourning doves) and one violation of the National Wildlife Refuge Act (possession of a firearm on the Refuge) totaling $650.00 in fines. The City issued a letter of reprimand including seven points of what was expected of the NIC director. In addition, his salary was frozen for six months, eliminating a $1,890,00 cost-of-living increase. 25

I. EQUIPMENT AND FACILITIES

1. New Construction

The only facility currently present on the Refuge is the NIC. However, Opinion and Settlement mitigation requirements will generate various developments over the next two to four years. Proposals include: interpretive trails/overlooks, protective fencing, undergrounding NIC utilities, NIC access road refurbishment, culvert installation to promote tiiial influx, Jersey noise barricade installment along the I-5/Refuge boundary ttf'Vetard noise intrusion into the wetland zone, and placement of navigational buoys along the Refuge/San Diego Bay interface. Refuge staff, on an on-going basis, are assisting Caltrans and the Corps in defining details of said projects. It is uncertain at this stage whether the actions will be implemented by the Refuge, with external funding support, or by the other concerned agencies.

Refuge staff, YCC enrollees and staff from Salton Sea NWR combined to complete two significant projects. The vehicle barricade discussed in Section E.2 has proved very beneficial, as has the installation of a gate across the SDG&E access road (see Section E.3). This gate is an effective barrier to unauthorized vehicles.

2. Rehabilitation

This year's rehabilitation projects, almost all part of the Settlement, are described in Sections D.4, D.6, E.3, F.la, F.2 and F.6.

J. OTHER ITEMS

4. Credits

Written by Ronnie Ryno. Typing/assembly by Shelly Hunter. Photos are credited by initials: Marc Weitzel - MW; Ron Ryno - RR; William Henry - WH; Linda Foster - LF; Barbara Moore - BM.

liiii

Informative graphic displays discuss in easy-to- understand terms the ecology of salt marshes, the Pacific Fly Way (migratory path of birds along the West Coast), history of Gunpowder Point, and the rare and endangered plants and animals that inhabit the area. EDUCATION

This 4,500 gallon salt-water tank allows visitors to pet and hand-feed bat rays, sting rays, leopard sharks and various fishes The normally dangerous rays have been "debarbed" to permit handling by humans. Petting a sting ray is like nothing you've ever experienced! CHULA VISTA NATURE INTERPRETIVE CENTER ** A variety of exhibits at the Nature Center provide an experiential tour through the many environmental zones of the marsh—from the inter-tidal zone of the Bay through the coastal upland habitat. Many of the exhibits are interactive and provide a "hands-on" opportunity to experience the unique wildlife found in Southern California salt marshes.

The Center is located in the Sweetwater Marsh National Wildlife Refuge.

Get a close look at the snakes, insects, mice and other small creatures that inhabit the dry upland areas of the Sweetwater Marsh complex.

Within the Nature Center are over twenty aquaria containing unusual fishes andfanimals which are native to the coastal marsh environment and San Diego Bay. The Chula Vista Nature Interpretive Center is located in the Sweetwater Marsh National Wildlife Refuge, one of the few remaining salt marsh habitats on the Pacific Coast. The facility offers a rare look into the natural history and ecology of California wetlands. From the observation tower, you can witness the daily lives of over 130 species of birds—some rare, many taking a rest during their yearly migration, all unique and beautiful. Inside the Nature Center, take a trip below the surface of the marsh. Aquaria, terraria and other displays bring you eye-to-eye with the creatures that dwell in the water, on the shore and underground. Browse in the bookstore, catch the video program "Scenes From a Salt Marsh," or discover the many other wonders of this vanishing- natural resource. For a truly unforgettable experience guaranteed to raise your excitement level, visit the petting pool and introduce yourself to a sting ray, bat ray or one of the small sharks eager to take food from your hand. But don't worry—they won't bite.

r ,V

* The Chula Vista Nature Interpretive Center is located on the shore of San Diego Bay approximately seven miles south of downtown San Diego and seven miles north of the International Border. It sits among the several salt marshes that surround the mouth of the Sweetwater River. Because of the isolation of the Nature Center, private automobiles and pedestrians are not permitted. Access to the facility is available via convenient shuttle buses.

From Interstate 5, take the E Street exit in Chula Vista, go Groups and school classes may make advance west about 200 feet. Shuttle bus arrangements for special tours and pick-up and parking are clearly programs. Bird Walks are marked. conducted every other Or take the San Diego Trolley to the Bayfront/E Street Trolley weekend for the general Station and Visitor Information public. Contact the Nature Center. Shuttle buses are available Center for more information at either location and run every 20 minutes starting at 10:00 am. about these special programs. Persons seventeen and under ride free; persons over seventeen ride rrii /~ti i TT* , \T i , , . for 50 cents round trip. The shuttle ne Chub NatureVista InlerprelweCeale, is open lo service 1S d b^„ Transjt the public Tuesday through Sunday from 10 am to 5 pm. Admission is free; donations are welcome. Holiday schedules are as follows: Admission to the Nature Center is Closed: Thanksgiving, the day after free. Donations are accepted. Round Thanksgiving, Christmas Eve, trip shuttle service is 50 cents for Christmas Day, New Year's Eve, New Year's Day and Easter Sunday. persons over seventeen, free to persons seventeen and under. Open: President's Day, Memorial Day, the Fourth of July, Labor Day and Martin Luther King's Birthday; when these holidays fall on Mondays, the Center will be DISCOVERY open to serve the public and closed the immediately following Tuesday for routine maintenance". The Chula Vista Nature Interpretive Center is operated by the Bayfront Conservancy Trust, a non-profit, public benefit corporation, and the City of Chula Vista.Volunteers are needed to assist the paid staff with the operation of the facility. If you would like to help, contact the Volunteer Coordinator at the phone number given below. Membership in Friends of the Nature Interpretive Center is also available by contacting the Najuxe Center. The Bayfront Bookstore, located in the Center, offers many naturalist books andjsupplies.-^

CHULA VISTA NATURE INTERPRETIVE CENTER 1000 GUNPOWDER POINT DRIVE CHULA VISTA, CA 92010 (619) 422-BIRD Cover photo: © 1989 Phillip Roullard Other bird photos: Mike Armbrust Aerial photo by Jeran Aero-Graphics throughout San Diego County. Materials are available in both Spanish and English. In conjunction with the Reserve, the local YMCA Camp Surf offers an internship program with interns conducting elementary school tours of the estuary. Special "exploring kits" have been developed for these excursions. A high school level curriculum is currently being developed through a San Diego County marine science education grant. Training will be offered beginning in 1989. Public nature walks through the Reserve are conducted on the first and second Saturday of every month from 9 a.m. to 11 a.m. The Reserve offers four miles of foot paths as well as access to 2.2 miles of beach.

Support Facilities A 6,800 square-foot visitor center is scheduled for completion in 1989. The center will provide an exhibit hall, education laboratory, multi-purpose meeting room, administrative offices, reference library, map and photo library, multi-media equipment, and computer facilities.

TIJUANA RIVER

NATIONAL ESTUARINE RESERVE RESEARCH SYSTEM

For additional information, please contact: Tijuana River National Estuarine Research Reserve Caspian Way Imperial Beach, California 92032 Tijuana River Reserve: An Opportunity for Estuarine Research and Education

The Tijuana River National Estuarine Research Reserve encompasses approximately 2,531 acres of tidally flushed wetlands as well as riparian and upland habitats immediately north of the U.S. and Mexico border. The Reserve provides a coordinated resource management framework for a complex of federal, state, and privately owned lands in south San Diego county.

Research Research at Tijuana River Reserve provides an opportunity to study current resource management questions in a relatively undisturbed estuary which is in an urban setting. Research can be conducted in a broad range of habitats—dunes, beach, salt marsh, mudflats, salt pannes, coastal sage scrub, riverine and brackish marsh—and at the 70- acre Pacific Estuarine Research Laboratory (PERL). PERL is operated in cooperation with San Diego State University and supports research to improve management of the region's estuaries and wetlands. Research has focused on a variety of issues including the effects of wastewater discharges and watershed management practices on the estuarine environment. Monitoring programs have been established to track the influence of hydrological disturbances on the Reserve. PERL researchers have also conducted studies to develop estuarine and riparian habitat enhancement techniques and to assess the nature of artificial wetlands as a mitigation measure in the region.

Education Reserve school programs are structured around the M.A.R.S.H. Project (Marsh Awareness with Resources of Slough Habitats) curriculum developed for 5th and 6th grade students. During the fall and spring, training workshops using the materials in the field are offered for teachers and youth leaders NATIONAL ESTUARINE RESERVE RESEARCH SYSTEM if W- , fll1' i •>

WHERE RIVERS MEET THE SEA In the late igeO's the United States freshwater from the land. These Congress recognized the need to protect "brackish" waters make up the bays, coastal resources from pollution and the sounds, inlets, bayous, and sloughs pressures of development. In particular familiar to anyone who has visited the danger were the nation's estuaries, those coast. Though they lack the saltwater valuable, yet fragile areas where rivers component, freshwater wetlands found meet the sea. To address threats to these along parts of the Great Lakes' shorelines critical areas, the National Estuarine also have many estuarine-like Reserve Research System was established characteristics. Physical features typical of as part of the Coastal Zone Management estuarine systems include narrow river Act of 1972. The National Oceanic and and bay mouths emptying into the sea, Atmospheric Administration (NOAA) was barrier beaches protecting the estuary given responsibility for designating mouth, mudflats, saltwater and estuarine reserves and administering the freshwater marshes. System. Shallow basins within estuaries are warmed by the sun, and organic and mineral sediments in the waters are constantly mixed by ocean tides and currents. The results are fertile arms of the sea that provide food for an immense number of plants and animals either directly or indirectly through a complex food web.

Importance of Estuaries The goal of NOAA's program is to establish and manage, through federal- Estuaries are among the most state cooperation, a national system of biologically productive systems on earth. reserves representing different coastal More than two-thirds of the fish and regions and estuarine types that exist in shellfish commercially harvested in the United States and its territories. The coastal waters spend part or all of their Reserves serve as field laboratories in lives in estuaries. The economies of many which studies are conducted on natural coastal cities are directly linked to both and human processes occurring within commercial and recreational uses of the estuaries. estuaries. Millions of people enjoy fishing, boating, and related activities and also benefit from the food and employment created by the resources What is an Estuary? nurtured in estuarine systems. Estuaries also provide other benefits, including An estuary occurs where saltwater storm and flood protection and pollution from the sea meets and mixes with control, at no cost to taxpayers. The fragile balance of these productive Research estuarine environments may be easily destroyed by human activities. Changes National Estuarine Research in water quality or alterations (dredging Reserves are being established and or construction) to coastal barriers that managed for long-term environmental protect the mouths of these inlets can monitoring and scientific research. Each lead to destructive changes in the site offers opportunities for monitoring marshes and mudflats that lie behind. The changes within the estuarine system and National Estuarine Reserve Research the effects of human activity on these System is providing critical protection to resources. Research efforts in the safeguard these irreplaceable natural Reserves involve the active participation resources. of Reserve staff, academic institutions, and independent research foundations. Informational exchanges among researchers benefits the Reserves, the institutions using these areas as natural field laboratories, and the nation.

Outdoor Classrooms

Education and research are the primary objectives of the National Estuarine Reserve Research System. Educational programs, guided tours, and workshops are offered at most Reserves. The results of scientific research Many sites include facilities such as programs in the Reserves are important interpretive centers, laboratories, and sources of information and data to resource libraries. The public is support coastal zone management and encouraged to take advantage of these decision-making. Protection of estuaries opportunities to learn about their and the continuation of these research National Estuarine Reserves. Exciting programs are essential to help us better discoveries can also be made during an understand our nation's estuaries and informal visit, casual hike, or boat trip what we must do to keep them healthy through these beautiful natural areas. and productive. NATIONAL ESTUARINE RESERVE RESEARCH SYSTEM

Padilla Bay, WA

Wells, ME Great Bay, NH South Slough, OR Waquoit Bay, MA Narragansett Bay, Rl Hudson River, NY Chesapeake Bay, MD

Elkhorn Slough CA North Carolina (4 sites)

Tijuana River, CA Sapelo Island, GA

Weeks Bay, AL pvWaimanu, HI Apalachicola, Fl Rookery Bay, FL Jobos Bay, PR^

Alabama - Weeks Bay Hawaii - Waimanu Valley North Carolina Weeks Bay N.E.R.R. Waimanu Valley N.E.R.R. North Carolina N.E.R.R. Marine Resources Division Dept. of Land and Natural Resources Division of Coastal Management Dept. of Conservation & Natural Resources Natural Area Reserves System P.O. Box 27687 P.O. Drawer 458 1151 Punchbowl Street Raleigh, NC 27611-7687 Gulf Shores, AL 36542 Honolulu, HI 96813 (919) 733-2293 (205) 968-7575 (808) 548-7417 Ohio - Old Woman Creek California - Elkhorn Slough Maine - Wells Old Woman Creek N.E.R.R. Elkhorn Slough N.E.R.R. Wells N.E.R.R. 2514 Cleveland Road, E. 1700 Elkhorn Road P.O. Box 1559 Huron, OH 44839 Watsonville, CA 95076 Wells, ME 04090 (419) 433-4601 (408) 728-0560 728-2822 (207) 646-1SK Oregon - South Slough California - Tijuana River Maryland - Chesapeake Bay South Slough N.E.R.R. Tijuana River N.E.R.R. Maryland Chesapeake Bay N.E.R.R. P.O. Box 5417 Caspian Way Dept. of Natural Resources Charleston, OR 97420 Imperial Beach, California 92032 Tawes State Office Bldg. B-3 (503) 888-5558 Annapolis, MD 21401 Florida - Apalachicola (301) 974-3782 Puerto Rico - Jobos Bay Apalachicola N.E.R.R. Jobos Bay N.E.R.R. 261 7th Street Massachusetts - Waquoit Bay Dept. of Natural Resources Apalachicola, FL 32320 Waquoit Bay N.E.R.R. P.O. Box 1170 (904) 653-8063 P.O. Box 92W Guayama, PR 00655-0327 Waquoit, MA 02536 (809) 864-0105 Florida - Rookery Bay (508) 457-0495 Rookery Bay N.E.R.R. Rhode Island - Narragansett Bay 10 Shell Island Road New Hampshire - Great Bay Narragansett Bay N.E.R.R. Naples, FL 33962 Great Bay N.E.R.R. Dept. of Environmental Management (813) 775-8845 Dept. of Fish and Came 291 Promenade St. Marine Fisheries Division Providence, Rl 02908-5767 Georgia - Sapelo Island 2 Hazen Drive (401) 277-3165 Sapelo Island N.E.R.R. Concord, NH 03301 Game and Fish Division (603) 271-2501 Washington - Padilla Bay Dept. of Natural Resources Padilla Bay N.E.R.R. P.O. Box 15 New York - Hudson River 1043 Bayview-Edison Road Sapelo Island, GA 31329 Hudson River N.E.R.R. Mt. Vernon, WA 98273 (921) 485-2251 NYS Dept. of Environmental Conservation (206) 428-1558 Bard College Field Station Annandale, NY 12504 (914) 758-5193 The Reserve Research System

Presently, eighteen Reserves in fifteen states and Puerto Rico have been designated. Collectively, they protect nearly 300,000 acres of estuarine waters, marshes, shorelines, and adjacent uplands for research and education. Additional sites are under consideration to expand the System. The diverse environments represented by each Reserve provide a profile of the nation's estuaries—an invaluable tool for coastal zone decision-makers.

NATIONAL ESTUARINE RESERVE RESEARCH SYSTEM

For additional information on the National Estuarine Reserve Research System, please contact:

Marine and Estuarine Mgmt. Division Office of Ocean & Coastal Res. Mgmt. NOS/NOAA 1825 Connecticut Avenue, NW Washington, DC 20235 (202) 673-5126

Total copies printed: 40,000 Unit cost: $.0372 Publication date: 2/89 ••11

mm K A Walker's Guide

THE NATURAL HISTORY OF THE TIJUANA RIVER NATIONAL ESTUAR1NE RESERVE BIRDS

Over 340 species of birds have been sighted in the Tijuana River Valley. Red-throated Loon Pied-billed Grebe" Eared Grebe Western Grebe Brown Pelican Double-crested Cormorant [12] Great Blue Heron [13] Great Egret Snowy Egret" Cattle Egret Northern Pintail" Cinnamon Teal" American Wigeon Surf Scoter Red-breasted Merganser Ruddy Duck Osprey Black-shouldered Kite Northern Harrier Red-tailed Hawk Golden Eagle American Kestrel Light-footed Clapper Rail® [2] American Coot Black-bellied Plover 11 Snowy Plover" Killdeer" Black-necked Stilt" [8] American Avocet" [9] Willet [6] Whimbrel Long-billed Curlew [7] Marble Godwit [10] Sanderling Western Sandpiper [4] Dunlin [1] Dowitcher sp. [5] Western Gull Caspian Tern Elegant Tern Forester's Tern Least Tern6-" Mourning Dove" Say's Phoebe Common Raven Marsh Wren" Loggerhead Shrike" Least Bell's Vireo6-" Belding's Savannah Sparrow6 Song Sparrow" White-crowned Sparrow Western Meadowlark" House Finch"

e = Endangered species n = Nesting PLANTS HABITAT GUIDE Standing on the trail, looking out across the marsh, you SAND DUNES see a uniform landscape. But, unlike the mountains where Ambrosia Ambrosia chamissonis change is measured in hundreds of feet, change here is Beach Evening-Primrose Camissonia cheiranthifolia measured in inches. Salinity and tidal submergence are Sea-Rocket* [7] Cakile maritima two important factors which limit the growth of plants and Sand-Verbena [9] Abronia maritima animals. These two factors are regulated by the slight i LOW MARSH changes in intertidal elevation. Your eyes and feet will soon become accustomed to the many variations within this Batis^ [6] Batis maritima uniform landscape. Cordgrass Spartina foliosa Pickleweed [8] Salicornia virginica SAND DUNES MIDDLE MARSH Dunes protect the marsh from the ocean. These barriers Alkali Heaths [5] Frankenia grandifolia are a windblown, salty, arid environment for plants and Arrow-Grass Triglochin concinnum animals. The surface runners of sand verbena stabilize the Brass Buttons* Cotula coronopifolia dunes while acting to trap more sand. The California Least Jaumea Jaumea carnosa Tern6 nests on the dunes north and south of the river Sea Lavenders [3] Limonium californicum mouth. Dune restoration is a continuing management Salt Grassy [1] Distichlis spicata activity. HIGH MARSH MCJD FLATS AND TIDAL SLOUGHS Alkali Weed Cressa truxillensis Glasswort Salicornia subterminalis The soil is completely waterlogged and most of the species Salt Marsh Bird's Beak6 Cordylanthus maritimus are single-celled diatoms. In winter look for the bright Salt Marsh Dodder Cuscuta salina green algae, sea lettuce. An abundance of fish, surface Shoregrass [2] Monanthochloe littoralis insects, and invertebrates in the mud sediments and the Spiny Rush Juncus acutus water column, provide food for a variety of foraging birds. Suaeda [4] Suaeda esteroa The tides distribute nutrients and flush out waste products CJPLANDS twice a day. Bladder-Pod /somen's arborea Cactus, Coast Barrel Ferocactus uiridescens LOW MARSH Cactus, Cane Cholla Opuntia parryi war. serpentina With twice daily tidal inundation the soil salinity, J.b%, Cactus, Coast Cholla O. prolifera remains close to sea water. Co'rdgrass does well here and Cactus, Fishhook Mammillaria dioica is the preferred habitat for the Light-footed Clapper Rail6. Cactus, Mesa Prickly Pear Opuntia littoralis Cactus, Velvet Bergerocactus emoryi Few species of plants can survive frequent submergence California Encelia Encelia californica and soils with little or no oxygen. California Sagebrush Artemisia californica Dudleya, Chalk Dudleya pulverulenta MIDDLE AND HIGH MARSH Dudleya, Lanceleaf Dudleya lanceolata Dudleya, Orcutt's Dudleya attenuata ssp. orcuttii Fewer high tides reach this area but all leave behind their Dudleya, Slender Ladyfinger Dudleya edulis salt load. Soil salinities can become very high unless Coast Goldenbush Haplopappus uenetus flushed by an occasional winter storm. Ways that plants Flat-Top Buckwheat Eriogonum fasciculatum tolerate the high soil salt content include salt excretion Garland Chrysanthemum* Chrysanthemum coronarium (see crystals of salt on plant leaves), salt storage (see bulb­ Laurel Sumac Malosma laurina (Rhus) like hairs on the ice-plant), and salt exclusion (roots that Lemonadeberry Rhus integrifolia prevent salt uptake). A high diversity of plants lives here. Mesa Shrub-Globemallow Malacothamnus fasciculatus

RIVERBED UPLANDS Broom Baccharis Baccharis sarathroides Inches of elevation above the salt marsh is the coastal sage Bulrush Scirpus sp. scrub community. The aromatic sagebrush and flat-topped Cattail Typha spp. buckwheat are indicators of the change. The plants are Desert Elderberry Sambucus mexicana not tolerant of salty soil conditions and many are dormant Giant Reed* Arundo donax Mule-Fat Baccharis glutinosa during the dry summer. Quail Brush Atriplex lentiformis Tamarisk* Tamarix sp. RIVERBED Willow, Arroyo Salix lasiolepis Willow, Black Salix gooddingii The river usually flows only during and after the winter Willow, Sandbar Salix hindsiana rains. Throughout the year there is sufficient underground water to supply the many willows, cattails and bulrushes. Plants may also appear in Middle or High Marsh Endangered Species These plants provide a rich year round community for Mot native to North America songbirds and breeding habitat for the Least Bell's Vireo6.

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ijuana River • Picnic Area —— Foot Paths • Restrooms Mational .!•+ + + Horse Trails o Corral & Hitching Post O Visitor Center (1988) • Hitching Post Estuarine Reserve Entrance Points A Overlook THE RULES

HOW WOULD YOU RUIN A RESERVE? • All animals, plants and physical features are protected and may not "be removed or damaged. • Dogs are allowed only on the beach and must be on a leash.

YOCJ MAY FISH FROM THE BEACH, BUT • Fishing, clamming, shrimping, and related activites are prohibited in all other areas.

THE SALT MARSH IS EASILY DAMAGED BY TRAFFIC. TRACKS MAY LAST YEARS .... • Hike only on designated trails and along the beach. • Bicycles are not permitted on the trails and must stay on designated roads. • All vehicles must stay on designated roads. • Horses must remain on signed equestrian trails. Stay off the dunes!!

PLEASE RESPECT SPECIAL AREA CLOSURE SIGHS • The California Least Terne nesting sites (summer), and • Sand Dune restoration areas (year around).

IT WILL NOT SURPRISE YOU THAT ... • No weapons or fireworks are permitted anywhere in the Reserve. • No littering or dumping. Instead, feel free to pick up as much litter as you like!

The T. R.N.E.R. includes Border Field State Park and Tijuana Sloughs National Wildlife Refuge. The Reserve is operated by the California Department of Parks and Recreation and the G.S. Fish and Wildlife Service.

For information or to report a problem, call 435-5184 / 428-3034 To request educational information, call 237-6766

SOUTHWEST WETLANDS INTERPRETIVE ASSOCIATION

S. W. I. A. is a non-profit organization working in cooperation with the California Department of Parks and Recreation. It is dedicated to acquisition, preservation and interpretation of wetlands. For information and membership, write:

This brochure producted cooperatively by S. W, I. A, and the California State Coastal Conservancy Design • Pat Flanagan Photo • Bubar Art • Julie Nagata, Donovan Mclntyre, Cam Barrows

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