Oak Orchard/Tonawanda BCA Management Guidance Summary
Site Name: Oak Orchard/Tonawanda Bird Conservation Area
State Ownership and Managing Agency: New York State Department of Environmental Conservation
Location: Niagara County, Town of Royalton; Orleans County, Town of Shelby; Genesee County, Towns of Alabama and Oakfield.
Size of Area: 8,116 acres
DEC Region: 8, 9
General Site Information: Large complex consisting mainly of managed emergent marshes, swamps and other wetlands, as well as extensive grasslands. Large numbers of wetland dependent birds breed here, and the site is an important migratory stopover for waterfowl and wetland-dependent birds. Grasslands provide nesting habitat for waterfowl and numerous grassland bird species. These two state parcels (Oak Orchard WMA, Tonawanda WMA) are at opposite ends of the 11,000 acre Iroquois National Wildlife Refuge. As a whole these areas comprise over 19,000 acres of wetlands and grasslands, much of which have been managed to provide habitat for a variety of birds.
Vision Statement: Manage the area to conserve the diverse assemblage of bird species utilizing the area. In particular, nesting and migration habitat for wetland (waterfowl, marshbirds) and grassland dependent birds will be a primary focus, although bird utilization as a whole will take a prominent role.
Key BCA Criteria: Waterfowl concentration site; wading bird concentration site; migratory concentration site; diverse species concentration site; individual species concentration site; species at risk site; bird research site (ECL § 11-2001, 3. a, d-i). Wetlands support a tremendous diversity of wetland dependent birds, and are an important migratory stopover. Rare species include: black tern (endangered), short-eared owl (endangered), pied-billed grebe (threatened), least bittern (threatened), king rail (threatened), northern harrier (threatened), sedge wren (threatened), osprey (special concern), American bittern (special concern), red-shouldered hawk (special concern), common nighthawk (special concern), red-headed woodpecker (special concern), vesper sparrow (special concern), grasshopper sparrow (special concern), Cooper's hawk (special concern), sharp-shinned hawk (special Concern), prothonotary warbler. Other species of note include: bobolink, eastern meadowlark, savannah sparrow, Virginia rail, sora, common moorhen, American coot, American black duck, common snipe, great blue heron, and green-backed heron.
Critical Habitat Types: Emergent marsh interspersed with open water, grasslands, shrublands and wooded wetlands.
- Identify habitat management activities needed to maintain site as a BCA.
Maintenance of optimal water levels during breeding season and during migration is important. Stable water levels during breeding season would be beneficial to nesting success of black tern, least bittern, king rail, pied-billed grebe, and other marsh nesting species. An interspersion of open water and emergent marshes is highly beneficial to many species, such as, black tern, least bittern, king rail and waterfowl. This is accomplished by drawdowns and by muskrat management.
Control of invasive exotic plant species is needed. Biological controls for purple loosestrife have been implemented and seem to be having a positive effect on reducing the density and vitality of purple loosestrife, thereby reducing its competitive advantage and allowing native species to compete.
For grassland species and species that nest in grasslands near wetlands, mowing of grasslands on a regular basis (annually or semi-annually) will be needed to prevent natural succession. Areas within 150 meters of known northern harrier nests should be restricted from disturbance during the nesting season. Native warm season grasses could be restored to existing grassland areas or abandoned agricultural areas to expand or enhance habitat for grassland species.
- Identify seasonal sensitivities; adjust routine operations accordingly.
Many species of marshbirds are sensitive to water level fluctuations. Water levels should be kept as stable as practical during the nesting season (April 15 to July 31).
In most situations, the mowing of grassland areas will occur outside of the nesting season (April 15 to July 31).
- Identify state activities or operations which may pose a threat to the critical habitat types identified above; recommend alternatives to existing and future operations which may pose threats to those habitats.
Grassland areas will need to be mowed or burned periodically to maintain them as grasslands. Failure to mow will result in loss of grassland species habitat.
Site selection and construction of new dikes to create new marsh habitat should consider existing bird utilization of the areas to be flooded. Conversion of forested wetlands to marshes may result in loss of forest wetland species such as prothonotary warbler and cerulean warbler, as well as nesting habitat for herons.
Removal or natural succession of shrublands could lead to a loss or reduction in early successional species. Shrubland/early successional species are declining throughout the northeast, at a more rapid rate than most other species, including many marsh-dependent species. Shrublands provide an important habitat and add diversity to the area and should be maintained or enhanced where possible.
- Identify any existing or potential use impacts; recommend new management strategies to address those impacts.
Any uses that create waves could be detrimental to marsh nesting species. Heron rookeries and northern harrier nests are susceptible to disturbance. Limiting public access during the nesting seasons may be beneficial, if conflicts arise.
- Assess current access; recommend enhanced access, if feasible.
Access appears adequate.
- Determine education and outreach needs; recommend strategies and materials.
Kiosks, brochures, and public outreach programs that promote the ecology of marshes and grasslands, and the bird species that rely on them, would be beneficial. These should be coordinated with the activities at Iroquois National Wildlife Refuge, which has an established visitors center that also serves the state lands.
- Identify research needs; prioritize and recommend specific projects or studies.
Inventory of grassland species and habitats to assess utilization, and the potential to enhance this use is needed. Current monitoring and research programs for marshland birds should continue. Additional monitoring/ research is needed on pied-billed grebe and cerulean warbler.
Region 8 Wildlife Manager, 585-226-5460
New York Natural Heritage Program. 1995. Biodiversity Inventory Report for Tonawanda WMA. New York State Department of Environmental Conservation, Albany, NY.
New York Natural Heritage Program. 1993. Biodiversity Inventory Report for Oak Orchard WMA. New York State Department of Environmental Conservation, Albany, NY.
Wells, J. V. 1998. Important Bird Areas in New York State. National Audubon Society, Albany, New York.
Date BCA Designated: 10/22/02
Date MGS Prepared: 2/12/02