DEER

BrunnerKEENER (Lows) RD Island

West Donegal Township

RIVER RD Snitz Creek

MILLER

241

Lancaster County

Newberry Township R Conoy Creek D L IL York County M E ON ST STAC KS TOW D Bainbridge N R

ek noy C re Co

RIVER RD

East Manchester Township (LimitAeialof imagery) (Limit of Aeial imagery)

Lancaster County Natural Heritage Inventory Update 2008 Legend Species of concern core habitat Natural Heritage Area Roads Hellam Supporting Landscape PA Turnpike Township Streams All other roads Riparian Buffer Municipal Boundary

Miles 0 0.5 1 1.5 2 Brunner (Lows) Island Brunner (Lows) Island – Exceptional significance

PNHP Rank1 State Last Observed Species of Concern: Quality2 Global State Status1 (y-m-d)

Plants: Scarlet ammannia (Ammannia coccinea) G5 S2 PE 1997-08-10 C Tooth-cup (Rotala ramosior) G5 S3 PR 1997-08-10 C

Animals: Elktoe mussel (Alasmidonta marginata) G4 S4 - 2002-08-31 E Triangle floater mussel (Alasmidonta undulata) G4 S3S4 - 1999-08-06 E Yellow lampmussel (Lampsilis cariosa) G3G4 S3S4 - 2006-08-19 E Osprey (Pandion haliaetus) G5 S2B PT 2003 E Virginia Rail (Rallus limicola) G5 S3B - 1987 E

Sensitive species of concern (A)3 - - - 2002 E Sensitive species of concern (B)3 - - - 2003 E Sensitive species of concern (C)3 - - - 1996-05-30 D

1 Please refer to Appendix IV for an explanation of PNHP ranks and legal status 2 Please refer to Appendix V for an explanation of quality ranks 3 This species is not named at the request of the agency overseeing its protection

Location: This Natural Heritage Area includes the section of the Susquehanna River south of the borough of York Haven to the railroad bridge crossing the river at the mouth of . Brunner Island is directly across the river from the borough of Bainbridge in Lancaster County. o Municipalities: o Conoy Township, (Lancaster County) o Hellam Township, (York County) o East Manchester Township, (York County) o Newberry Township, (York County) o York Haven Borough, (York County) o USGS Quadrangles: o York Haven Quadrangle o 1990 Lancaster Natural Areas Inventory reference: o “Haldeman Island” – (York Haven Quadrangle)

Description: As enters the Susquehanna River it divides into several channels and cuts the delta-like Brunner Island (the lower portion is also called Lows Island) from the main shore of York County. Brunner Island is the site of a PPL owned coal-fired electric generating plant that began operating in the early 1960s. Several other large islands occur in this section of the river including Haldeman, Ely and Pole Islands. The majority of these islands retain most of their natural conditions. This portion of the river also contains an extensive region of bedrock outcrop, referred to as Haldeman Riffles,

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which is dramatically revealed during times of seasonally low water. A public hiking trail is along the remnants of the Canal.

Species of Concern Considerations: Plants: o Scarlet ammannia is a globally secure (G5) though state imperiled (S2) plant that inhabits various damp to wet habitats, especially on the sandy shorelines, mudflats and intermittently flooded zones of rivers, streams, and ponds, and may also be found in human-created disturbances that simulate natural habitats. Conservation of this habitat type will help this species to persist at this location. o Tooth cup is a globally secure (G5), state rare (S3) annual plant that occupies exposed shorelines, stream margins, streambed outcrops, and other damp, open places. The populations of toothcup that occur along streams and rivers can be enhanced by maintaining the natural seasonal fluctuations in the water level of the stream and the natural conditions of its shoreline. Animals: o Ospreys have been increasing in number along the Susquehanna River and its tributaries due to a reintroduction program in the 1980s. These birds adapt readily to human activity and often construct nests on man-made structures (Brauning 1992). Being primarily fish eaters, Ospreys utilize aquatic habitats for food gathering and upland habitats or prominent features as nesting areas. The forested edge of the river, as well as the aquatic habitat of the river are both important components of this species habitat preferences. o Three freshwater mussel species of concern, elktoe, triangle floater and yellow lampmussel, along with four additional species of mussels were documented in this section of the Susquehanna River by local naturalist, Larry Coble. Historically, the dwarf wedge mussel, a federally endangered species, was also documented as occurring in the Susquehanna River near this location. Mussels are filter feeders and are strongly impacted by poor water quality and unsuitable creek bed substrate. Mussels exist as a parasite on certain fish species in their early life stage, and decreased populations of the host fish can negatively affect mussel populations. Dams that impede fish migration also restrict the habitat available to mussels. All streams, creeks and tributaries to the Susquehanna River should have wide forested/vegetated buffers in order to help ensure proper water quality for freshwater mussel habitat. Impediments to fish movement such as dams and improper stream crossings should be corrected to improve available habitat for mussels and their fish hosts. o The river is habitat for a sensitive species of concern documented over several years at this location. Maintain and improve water quality and movement above dams for fish migration to improve the habitat for this species of concern. o Two additional sensitive species of concern were documented along this stretch of the river. The core habitat for these sensitive species of concern is both the river and the adjacent upland forest. These sensitive species of concern require an abundant food source in the river and breeding areas in the adjacent upland forest. This can be achieved by preserving and improving the water quality of the Susquehanna River and by protecting and expanding the natural vegetation buffer along the river and all its tributaries

Forest Cover / Natural Communities: The plant community types depicted are only approximations delineated from 2005 aerial photography interpretation and were followed up with minimal selective ground-truthing. Community types follow “Terrestrial & Palustrine Plant Communities of Pennsylvania” (Fike 1999) where appropriate, and describe general land cover types where they are not. o This Natural Heritage Area is drawn relatively tightly around the river and the immediately adjacent uplands. The natural community types present represent the floodplains and upland forests in immediate proximity to the river. The dominant natural community types are: o Terrestrial (upland) communities:

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o Hemlock-tuliptree-birch forest o Tuliptree-beech-maple forest o Palustrine (wetland) communities: o Red maple-black gum palustrine forest o Red maple-elm-willow floodplain swamp o River birch-sycamore floodplain scrub o Silver maple floodplain forest o Sycamore (river birch)-box elder floodplain forest

Ownership: o Most of the islands in this section of the river are privately owned. o Three small, but ecologically significant islands are owned by the Commonwealth of Pennsylvania. o A small piece of Haldeman Island and a significant portion of the eastern shore of the Susquehanna River north of Bainbridge is owned by the PPL Corporation.

Habitat Disturbances: o Historic – The landscape surrounding this Natural Heritage Area was gradually cleared of its original forest cover over 200 years ago and replaced by the intensively cultivated landscape that we see today. o The borough of Bainbridge was built along the banks of the Susquehanna River. o The Pennsylvania Canal and then the Pennsylvania Railroad line were built along the eastern shore of the river and a railroad was built along the western shore of the river as well. o Numerous roads were built as infrastructure for the growing population of the area. o Most of the adjacent land in Lancaster and York counties was in agricultural production, with scattered quarry operations in 1940. o Brunner Island was almost entirely in active agricultural production based on aerial photographs taken in 1940. o The small channel that used to separate Brunner Island from Lows Island was filled. o The PPL coal-fired electric generating plant was opened on the island in 1961. o Current – o Most of the eastern and western shorelines of this section of the river fail to function as a terrestrial habitat corridor through the region. A much wider and enhanced vegetated buffer is needed adjacent to the floodplain on both shores of the Susquehanna River. While the Susquehanna River acts as a primary migratory pathway for many species of birds and bats, the vegetated area between the railroad tracks and the river is in most areas too narrow to adequately function as a regional terrestrial habitat corridor. Animals traveling northward though the extensive forested River Hills area of Lancaster County are suddenly forced into a very narrow strip of land between the river and the railroad tracks to avoid the heavily urban, suburban and agricultural land uses north of Turkey Hill. Similarly, the extensively forested areas in the southwestern shore of the river in York County dissipate northward where the landscape has been converted to agricultural and urban land uses. o The habitat of Bruner Island has been almost entirely converted to industrial uses though the perimeter of the island remains vegetated. Coal piles, fill and residue cover most of the island area, which can lead to coal pile runoff and decrease river water quality. Water heated by coal to produce steam for electric generation is returned back into the river, raising the local temperature of the surrounding river water. o In contrast to some of Lancaster County’s more intensively cultivated landscapes, many of the streams and smaller tributaries to the Susquehanna River have retained moderately

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sized vegetated buffers despite the high level of agricultural conversion of the natural landscape. These narrow habitat corridors help provide a natural environment for native species of plants and animals, but due to the narrowness of the corridor in the disturbed landscape, are typically strongly dominated by invasive species of plants. o Residential development activity is increasing in the Conoy Creek watershed. o Illegal dumps occur scattered throughout the river floodplain. o Exotic Species – The natural disturbance of seasonal flooding and ice scour create ideal conditions for many introduced species of plants. Consequently, the river shoreline is prone to invasion from a large number of invasive species. In addition, when cultivated land is idled, it is highly susceptible to invasion by aggressive invasive plants. Some of the former fields and clearings along the river have succeeded to a very weed infested woody landscape. The Pennsylvania Canal trail is particularly infested with invasive species of plants. Native grapevines contribute to the tangled aspect of the forest. Invasive species observed include: o Norway Maple (Acer platanoides)

o Tree-of-heaven1 (Ailanthus altissima) o Common mugwort (Artemisia vulgaris)

o Japanese1 & European barberry (Berberis thunbergii, Berberis vulgaris)

o Oriental1 bittersweet (Celastrus orbiculatus)

o English1 ivy (Hedera helix) o Asiatic day lily (Hemerocallis fulva) o Common privet (Ligustrum vulgare, Ligustrum obtusifolium)

o Japanese1 honeysuckle (Lonicera japonica)

o Bush1 honeysuckles (Lonicera morrowii, Lonicera maackii)

o Purple1 loosestrife (Lythrum salicaria)

o Japanese1 stilt grass (Microstegium vimineum)

o Princess1 tree (Paulownia tomentosa) o Common reed (Phragmites australis)

o Japanese1 knotweed (Polygonum cuspidatum) o Mile-a-minute (Polygonum perfoliatum) o Callery ‘Bradford’ pear (Pyrus calleryana) o Jetbead (Rhodotypos scandens)

o Multiflora1 rose (Rosa multiflora)

o Wineberry1 (Rubus phoenicolasius)

Conservation Actions:

Overall: o Coordinate the protection of this landscape between Lancaster and York Counties. o Protect and expand the natural vegetation along both shores of the river floodplain and adjacent upland. Consider expansion of a wide strip of native vegetation as a terrestrial habitat corridor along both shores of the river. o Avoid building, replacing or expanding dams on the Susquehanna River. o Riparian corridors of all stream tributaries to this section of the Susquehanna River and the river shoreline itself need additional restoration measures. Several stretches of streams in this area lack vegetated riparian buffers and are nearly or fully unprotected from agricultural and urban runoff. o High water quality and appropriate substrate are both critical aspects to sustaining suitable habitat in this section of the river. Establish at least 100 meter buffer of woody vegetation along the river shore and all segments of tributary streams to help protect the water quality of the river by reducing erosion, sedimentation, and pollution. Additionally, best management practices (BMPs) that focus on limiting nutrient and soil loss into surface and groundwater

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should be applied to surrounding agricultural lands. This would help maintain and improve water quality in the river.

Within the Core Habitat: o Most of the species of concern core habitat occurs along the shorelines of the islands and of the adjacent river floodplain. Maintain the natural hydrology of the river system by avoiding building dams or draining or permanently flooding adjacent wetlands. Preserve and improve the water quality of the Susquehanna River to help provide a continued and increased food chain. Maintain and improve water quality of the river by providing vegetated buffers along inflows to the river and along the river shoreline. Detention basins and rain gardens can be incorporated into borough infrastructure to allow stormwater to be filtered before entering the river. o The industrialization of Brunner Island severely limits the short tem potential for habitat restoration on the majority of this island. The perimeter of the island is in a relatively natural condition and should be preserved and expanded as area is available. The area along Wago Road is one of the narrowest vegetated buffers for the island. Shallow areas along the perimeter of the island should not be dredged. Material piles on the island should be strongly contained or covered to prohibit runoff from entering the river. The PPL Corporation maintains nature preserves and hosts many nature related activities for the public on this island as well as its other landholdings in Lancaster & York Counties. These activities help promote local stewardship of important natural resources. o The river floodplain between the river shoreline and River Road north of Bainbridge Borough should be considered a priority for conservation and expansion of natural habitats, and would be suitable for a passive recreation park. The area currently has a walking trial along the old Pennsylvania Canal. Emphasis for restoration in this area should be on promoting a viable floodplain natural community and protection of the natural condition of the shoreline rather than the addition of active park facilities and infrastructure. o Other large islands should be considered a priority for conservation acquisition or easements. Biological inventories of these islands are recommended.

Within the Supporting Landscape: The supporting landscape was drawn to include a 300 meter buffer to this section of the Susquehanna River and a 100-meter riparian buffer for all tributaries. Activities and land use patters in the adjacent subwatersheds can have a significant impact on the water quality of the river and the habitats of the species of concern. o Most of the conservation actions for the core habitat also apply to the supporting landscape. o The long term goal for the area should be to restore mature floodplain forests and the associated upland buffer forests along both shores of the river. Expand the native vegetation along the river corridor to ideally include land within 300 meters of the river’s banks. Reforestation efforts should be designed to mimic the adjacent natural community type by planting a similar composition of native trees and shrubs of varying age classes. Reforestation is a labor intensive effort that requires long term monitoring and maintenance to avoid infestation by invasive species of plants. o The rainwater runoff from the agricultural, urban, suburban and industrial sources should be considered a potential source of significant contamination for the river. Runoff from these sources have significantly higher levels of sediment, nutrients, pesticides, herbicides and other pollutants than runoff filtered through a natural habitat. Stormwater management measures such as the creation of detention basins or vegetated swales should be implemented within Bainbridge and other urban/suburban lands to slow the overland movement of stormwater. Existing wetlands also fulfill this function without the need for additional expenditures. o The surrounding intensively cultivated landscape offers only modest natural habitat for native species of plants and animals. Conoy Creek has a respectable riparian buffer through Conoy

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Township and should be considered a priority for conservation. There are, however, intermittent agricultural fields that abut the creek with very little buffer. Within West Donegal Township the riparian buffers dwindle to inadequate on many of the smaller tributaries feeding the larger Conoy Creek. These small feeder streams can have a significant impact on the overall sediment and pollution load of Conoy Creek and should be considered priorities for restoration of vegetated riparian buffers within this watershed. o Pursue conservation easements and fee simple acquisition on properties along the river shoreline to help conserve and improve the effectiveness of the Susquehanna River as a natural corridor. o Potential zoning options for conservation enhancement: o Conoy Township has a zoning ordinance restricting new construction within the 100-year floodplain of all waterways. Strict enforcement of this regulation will help prevent conversion of the floodplain to many unsuitable uses and help protect most of the species of concern core habitat. o Floodplain regulations should be updated to prohibit agricultural activities within the 100-year floodplain as well. Chemical, nutrient and sediment runoff into waterways from agricultural sources can be significantly reduced by returning seasonally flooded areas to natural habitats. o Parcels currently in agriculture outside of the floodplain that are of high quality agricultural soils should be zoned agricultural and considered fully built-out. Poorer quality agricultural soils and those in the 100-year floodplain should be encouraged to regenerate into forest cover. o Growth within the Township should be discouraged to occur within 300 meters of the 100-year floodplain of the river or within 100 meters of the floodplain of its tributaries. o Growth should be encouraged to occur clustered in close proximity to existing infrastructure to avoid unnecessary habitat destruction though suburban sprawl. o Potential restoration activities: o Numerous historic milldams occurred along the length of Conoy Creek and its branches. An analysis of the legacy sediments these dams trapped and the feasibility to restore the original topography should be conducted prior to replanting efforts. All tributaries to the Susquehanna River should be restored to native trees and shrubs to provide an increased buffer for storm water and agricultural runoff filtration, and to provide habitat diversity for a wider range of native plants and animals. Expansion of native vegetation along the creeks and streams will also provide greater connectivity between and among the adjacent natural habitats, providing a corridor for animal and plant movement within this portion of the county. o Streams through forested areas should be considered high priority for conservation. The forested riparian corridor helps to regulate the temperature of the stream and creates streamside conditions that contribute to improved water quality and aquatic habitat. Streams through non-forested areas should be reforested with native trees and shrubs appropriate to the habitat. Other narrow waterways in the supporting landscape have been strongly channelized and the lack of vegetated riparian buffers provides little, if any, protection from agricultural runoff. Careful determination is needed to avoid planting trees in floodplains that contain herbaceous wetland habitats. These habitats should be maintained in their current open condition, with tree plantings to occur at the periphery of natural wetland openings. o Ideal forested stream buffers should be 100 meters (~300 feet) in width from the edge of the 100-year floodplain o Intermediate forested stream buffer of 100 feet in width from the edge of the 100-year floodplain

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o Minimum forested buffer of 35 feet in width from the edge of the 100-year floodplain o Take into account the presence of legacy sediments at historic milldam locations and appropriately restore the historic floodplain as feasible. o Priorities for restoration of historic floodplain topography should be where the end result would be a functioning wetland habitat. o Remove invasive species of plants. The river floodplain is naturally susceptible to weedy plant invasion and will require a sustained and targeted approach to invasive management. Aggressive invasive species along the floodplain can have a significant impact on the available habitat for the species of concern, which can occupy much the same habitat as many invasive species. Control of invasive species along the river floodplain will require extensive and continual effort. Focus non-chemical control efforts on selected areas surrounding species of concern. o Target pioneer populations of invasive plants for immediate and continued removal, particularly tree-of-heaven, non-native bush honeysuckles, Japanese honeysuckle, multiflora rose, common privet, Jetbead, and callery pear. It is much easier and more effective to keep a place invasive-free than to try and repair a heavily infested habitat. o Invasive species are a significant feature along the old canal and railroad rights-of-way. However, indiscriminate use of herbicides as rights-of-way defoliants is not acceptable. A smarter, more selective use of chemical controls is required in these areas that contain both invasive species and species of concern. o Invasive species management needs to be coordinated by individuals familiar with the rare species as well as the invasive species present. o Continual invasive species monitoring and control will be necessary. o Illegal dumps should be removed and monitored for future activity. o Litter removal along the shores of the river will need to be conducted on a periodic and continual basis due to the seasonal flooding regimen of the river.

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