Partners in Flight: Mid-Atlantic Coastal Plain Bird Conservation Plan (Physiographic Area #44)

B. D. Watts, The Center for Conservation Biology

Abstract

Area - 5,460,600 ha Description - The Mid-Atlantic Coastal Plain extends from the Atlantic Ocean, south of Long Island, to the Fall Line, where the hilly Piedmont begins. It is arbitrarily separated from the South Atlantic Coastal Plain at the Virginia-North Carolina border (which the exception of the Great Dismal Swamp in the southeast corner of Virginia, which is grouped in the southern area). The area was formed by shifting sea levels and alluvial deposition from rivers draining mountains to the west. Water continues to be a dominant feature of the landscape, creating forested wetlands and salt marsh and shaping barrier island and bay complexes. Upland forests on the remaining land graded in composition from pine dominated areas on the outer Coastal Plain (nearer the coast) to hardwood forests on the inner Coastal Plain. This was the site of the first successful English settlement in North America, and the natural landscape has been altered by European culture for nearly four centuries. The current human population approaches 11 million and is expected to continue to expand into the future, placing ever-increasing demands on the region’s natural resources. Priority bird species and habitats - Pine savannah - Red-cockaded Woodpecker -- Federally endangered; remnant population reduced to as few as three breeding clans. Prairie Warbler -- Declining; native to open pine savannah; also in early succession habitat. Bachman’s Sparrow -- Northern edge of breeding range; requires open, grassy understory Objective: Restore enough pine savannah to support 20-25 clans of Red-cockaded Woodpecker (pre 1970s population); maintain breeding population of 2,600 Brown-headed Nuthatches. Salt marsh - Salt-marsh Sharp-tailed Sparrow -- Large proportion of world population breeds here; requires high marsh with buffer, stable water levels. Black Rail -- Status poorly known; requires high marsh with buffer. Seaside Sparrow -- Large proportion of East Coast population; wider habitat tolerance than sharp-tailed sparrows American Black Duck -- Important breeding and wintering populations Objective: Numerical population and habitat-area objectives for priority marsh birds have not yet been determined. Roughly 20,000 ha of marsh may be required to support 3,000 breeding pairs of American Black Ducks. Forested wetlands - Cerulean Warbler -- Poorly monitored; small populations along forested rivers; Swainson’s Warbler -- Disjunct population at northern edge of range; requires dense shrubby understory; Prothonotary Warbler -- Good indicator species for permanently forested wetlands; cavity nester; Acadian Flycatcher -- Habitat generalist in wet or moist deciduous forests with dense understory. Objective: Roughly 300,000 ha of forested wetland is required to support entire habitat-species suite, including 100,000 pairs of Acadian Flycatchers and 16,000 pairs of Prothonotary Warblers. Mixed upland forests - Wood Thrush -- Prefers moist deciduous forest with dense with well-developed mid-story. Worm-eating Warbler -- Expanding population; associated with dry, sloped forest with dense understory; ground nester. Kentucky Warbler -- Requires moist deciduous forest with dense understory and ground cover. Objective: Roughly 1 million ha of mature deciduous forest is required to support entire habitat-species suite (e.g. 300,000 pairs of Wood Thrush). Early successional - Henslow’s Sparrow -- May be one of the few remnants of the Eastern subspecies. Occurs in variety of habitats including the high dry edges of salt marsh habitat, very young regenerating pines, and (formerly) grasslands. Conservation issues and recommendations - Managing human population growth while maintaining functional natural ecosystems is the greatest conservation challenge facing land managers in this region. The future of wildlife habitat depends on protection of patches of conservation significance and the manner in which inevitable continuing growth alters the environment. Retention of populations of the highest priority birds, including the Red-cockaded Woodpecker, Piping Plover, and Henslow’s Sparrow, will require active protection and management of key sites. Forest habitat remains relatively abundant, but is very heavily fragmented. Identification and maintenance of those blocks large enough to support the full array of breeding birds should be a priority. Because of the close juxtaposition of coastal maritime, inland freshwater, and upland habitats, integrating the conservation objectives of priority land birds with those of waterfowl, shorebirds, and colonial-nesting waterbirds will be a high priority in the near future. Protection of critical sites for transient and wintering species also needs to be integrated with conservation plans for breeding habitats. Specific conservation recommendations for this physiographic area include: • Identify and restore tracts of pine-savannah habitat with the potential to support Red-cockaded Woodpecker clans within the next 20 years; • Establish burning program to maintain structural conditions in understory of existing pine-savannah • Continue strict protection of beach and barrier dune habitat to minimize productivity losses by priority species; • Identify, prioritize, and protect all sites with > 50 ha of high marsh; • Identify and protect forest blocks that support significant populations of Prothonotary, Cerulean, and Swainson’s Warbler; or Wood Thrush; • Identify, and either acquire, manage or restore open lands > 50 ha with potential to support Henslow’s Sparrow.