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Ecological restoration work is underway in the John Heinz National Wildlife Refuge at Tinicum in Philadelphia, Pennsylvania, which is celebrated as America’s First Urban Refuge. Friends of Heinz Refuge hired Princeton Hydro and teammates Enviroscapes and Merestone Consultants to provide engineering design, environmental compliance, engineering oversight, and construction implementation to enhance and restore aquatic, wetland, and riparian habitats and adjacent uplands within the Turkey Foot area of the Refuge.
The Turkey Foot project area is an approximately 7.5-acre site within the greater 1,200-acre John Heinz National Wildlife Refuge, which is located within the City of Philadelphia and neighboring Tinicum Township in Philadelphia and Delaware Counties, about one-half mile north of Philadelphia International Airport.
The Refuge protects approximately 200 acres of the last remaining freshwater tidal marsh in Pennsylvania and represents an important migratory stopover along the Atlantic Flyway, a major north-south flyway for migratory birds in North America. It also provides protected breeding habitat for State-listed threatened and endangered species, as well as many neotropical migrants, such as the American Bittern, Least Bittern, Black-crowned Night-heron, King Rail, Great Egret, Yellow-crowned Night-heron, and Sedge Wren.
The Refuge was established for the purposes of preserving, restoring, and developing the natural area known as Tinicum Marsh, as well as to provide an environmental education center for its visitors. The Refuge contains a variety of ecosystems unique in Pennsylvania and the Philadelphia metropolitan area, including tidal and non-tidal freshwater marshes, freshwater tidal creeks, open impoundment waters, coastal plain forests, and early successional grasslands. Although many of the Refuge’s ecosystems have been degraded, damaged, or, in some cases, destroyed as a result of numerous historic impacts dating back to the mid-17th century, many of these impacted ecosystems have the potential to be restored or enhanced through various management and restoration efforts.
The Turkey Foot project area is an example of one of the historically impacted ecosystems at the Refuge with tremendous opportunity for ecological restoration. The Friends of Heinz Refuge and the project team are working to restore and enhance the aquatic habitats, wetlands, riparian buffers, and adjacent uplands within the project area.
The approach for the restoration project focuses on creating approximately four acres of contiguous wetland habitat bordered by a functional riparian buffer. The design includes the creation of three habitat zones: intertidal marsh, high marsh, and upland grassland.
Incorporating the three elements into the landscape will help to establish foraging, breeding, and nesting habitat for critical wildlife species, including Eastern Black Rail, a threatened species listed under the Endangered Species Act of 1973.
The project work also includes a robust invasive species management plan, aimed at removing close to 100% of the invasive species, supported by an adaptive management monitoring program that will guide the development of the restored site towards the ultimate goal of establishing a diverse and productive coastal ecosystem within the Turkey Foot project area.
The upland slopes of the high marsh were seeded earlier this year, which will help to establish a grassland dominated by native warm season grasses. Native shrubs and flowering plants were also installed, including little bluestem, switchgrass, Virginia wild rye, asters, goldenrods, and bergamot. And, coastal panic grass was seeded, which is another Pennsylvania-listed endangered species, and, once grown-in, will provide suitable stopover foraging and cover for migratory land birds and pollinators.
The team also completed site grading to increase tidal flushing within the Turkey Foot’s two ponds, create intertidal and high marsh wetlands, prevent stagnant water and nutrient accumulation in bottom sediments, and reduce the reestablishment of invasive species. The bottom of the existing ponds were raised to elevations that support the establishment of intertidal marsh. The pond banks were then regraded to create the appropriate elevations for freshwater intertidal marsh and high marsh. Additionally, the tidally influenced connection points between the two ponds and the linear channel were enlarged.
Refuge Manager Lamar Gore recently visited the Turkey Foot project site and interviewed Deputy Refuge Manager, Mariana Bergerson, and Princeton Hydro Director of Restoration and Resilience, Christiana Pollack, about the progress made thus far and what’s to come. Watch now:
In Spring of 2023, the team will install a wide variety of native wetland plant species plugs and continue its work to restore the riparian buffer habitats within the Turkey Foot project area. The high marsh will be planted with a mix of native coastal plain wetland species, including fine-stemmed emergent plants, primarily rushes and grasses, with high stem densities and dense canopy cover, using species such as chairmaker’s bulrush, river bulrush, blue flag, and rice cutgrass. The installation of river bulrush, a Pennsylvania-listed rare species, will provide beneficial wildlife habitat and serve to expand the range of this species in Pennsylvania. Additionally, restoring the high marsh will create the foundation for establishing Black Rail habitat and giving the threatened species protection from predators and opportunities to glean insects and other invertebrates from the ground and water.
The restoration and enhancement of riparian buffer habitats will reduce sedimentation and lower pond temperatures, improving water quality for native fish and invertebrates. Riparian buffers also filter nutrients in runoff and deter eutrophication of the ponds, and provide high quality food sources for native and migratory species, unlike the invasive species which provide low nutrient value foods.
Please stay tuned to our blog for more project updates once the plantings have been completed in the Spring, as well as before and after photos once the plants are established. To read more about Princeton Hydro’s robust natural resource management and restoration services, click here.
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