Birds

Breeding Bird Surveys indicate that about 30% of the species that breed in the SBR have declined sharply in the last 30 years, and an additional 18% have shown declining trends (Hunter et al 1999). The number of species declining in the SBR exceeds that found in any other physiographic area in the southeast (James et al. 1993, Hunter et al. 1993). The Amphibolite Mountains have been designated an Important Bird Area (IBA) by the Audubon Society, one of 96 such designated areas in North Carolina. These are places that provide essential habitat for one or more species of birds at some time during their annual cycle of breeding, migrating or wintering. The SBR contains habitat essential for hundreds of breeding, migrant, and wintering birds. The mountains serve as geographic landmarks for many neotropical songbirds as they migrate from breeding grounds in the northern U.S. and Canada to their wintering grounds in Central and South America (Franzreb and Phillips 1996).  Ninety-eight migrant landbird species nest in the Southern Appalachians, the majority of which are Passeriformes, perching or songbirds such as thrushes, warblers, and tanagers (Franzreb and Phillips 1996). Fourteen orders and 34 bird families are represented in the Southern Appalachians with neotropical migrants comprising about 48% and short-distance migrants make up about 22% of the breeding bird species (Franzreb and Phillips 1996).

 

BMP’s high-elevation hardwood forests are especially important for a number of priority bird species including veery, black-throated blue warbler, Blackburnian warbler, rose-breasted grosbeak, solitary vireo, blue-headed vireo, dark-eyed junco, chestnut-sided warbler, Canada warbler, (Franzreb and Phillips 1996; Hunter et al. 1999).  The yellow-bellied sapsucker and ruffed grouse use these habitats and both species have suffered significant declines in this region over the past 20 years. Yellow-bellied sapsucker is a Southern Appalachian endemic that prefers a mix of mature and regenerating forest above 3500’ with some natural or anthropogenic disturbance. Reductions in natural disturbance regimes such as fire have contributued to the widespread declines in this species. Early-successional patches of high-elevation forest are also important for golden-winged warbler and ruffed grouse (Hunter et al. 1999). Northern goshawk and long-eared owl could potentially breed at BMP, although the nearest confirmed populations are from southern Virginia.

 

Northern Hardwoods that contain yellow birch, beech, sugar maple and buckeye often provide more abundant natural cavities and decaying wood than spruce or fir for species such as yellow-bellied sapsuckers, black-capped chickadees, and northern saw-whet owls (NCWRC 2005). Although no species are restricted to Northern Hardwoods, approximately 51% (50 species) of Southern Appalachian migrant landbirds use this habitat during the breeding season (Franzreb and Phillips 1996). Closed-canopy conditions that predominate Northern Hardwood forests have decreased habitat for bird species that rely on diverse understory, such as Canada warbler (NCWRC 2005). Suppression of disturbance has reduced available habitat for disturbance-dependent species such as golden-winged warbler (Hunter et al. 2001).s

 

Approximately 62% (61 species) of Southern Appalachian migrant landbirds use Cove Hardwood Forest during the breeding season (Franzreb and Phillips 1996). These forests are important for cerulean warbler and Swainson’s warbler (Hunter et al. 1999). Cerulean warblers prefer mature cove forests with large and abundant tulip poplar and white oak, and are restricted to this habitat type in breeding season. Swainson’s warbler prefers lower- elevation rhododendron thickets along streams and the SBR represents the most inland and northerly populations. Cove forests with a well- developed shrub layer support hooded warblers and a suite of neotropical migrant such as black-throated blue warbler, Acadian flycatcher, pileated woodpecker, whit-breasted nuthatch, worm-eating warbler, hooded warbler, scarlet tanager, ovenbird, Canada warbler, wood thrush, and blue-headed vireo—many of whom need a landscape of >70% forest cover to maintain breeding populations.  Ovenbirds prefer more sparse shrub layers. Blue-headed vireo is most abundant in mature cove forest; this is also particularly good habitat for scarlet tanager and Acadian flycatcher (Hunter et al. 1999). In young (post-timber harvest) cove forests, bird species richness can be very high, and many of these priority species also use young forest habitat.

 

Approximately 84% (82 species) of Southern Appalachian migrant landbirds can be found in oak-dominated habitats, but species composition can vary considerably based on elevation, forest structure, and micro-climate. Oak forests are important to birds primarily due to the expansive forest cover it represents throughout the SBR (50%).  Although no species are restricted to this forest type, minimally-fragmented, late-successional oak forests provide suitable and optimal habitat for almost every species of woodpecker that occurs in the SBR as well as many species of hawk (Hamel 1992), but these foresty types support lower relative bird densities and fewer species (Katz 1997).  Other representative species are the red-bellied woodpecker, hairy woodpecker, downy woodpecker, Carolina chickadee, tufted titmouse, wood thrush, red-eyed vireo, yellow-throated vireo, black-and-white warbler, yellow-throated warbler, pine warbler, hooded warbler, yellow-breasted chat, and scarlet tanager.  Riparian areas within oak woodlands provide habitat for Kentucky and hooded warbler, Louisiana waterthrush, and Acadian flycatcher.  Oak forest regeneration in all age classes have been shown to provide nesting and foraging habitat for many early-successional species including, golden-winged, prairie and chestnut-sided warblers, northern bobwhite, field sparrow, yellow-breasted chat and indigo bunting.

 

Early-successional habitat to is important for post-fledgling mature forest bird species (Anders et al. 1998, Vega Rivera et. al. 1998) and provide essential foraging and nesting habitat. These sites produce abundant soft mast late summer and early fall.  Early successional habitat describes forests generally less than 20 years old includng old and abandoned fields, wildfire hotspots, high-elevation grass and heath balds, mountain wetlands, even-aged timber management, and agricultural cropland and pastures. Early succession habitats are created and maintained by natural disturbances including grazing, flooding, tornadoes, hurricanes, ice storms, and fire. Fire suppression, elimination of bison and elk, decline in timber harvest, and conversion of small farms has resulted in the loss of most early successional areas.  About 100,000 acres (1%) of the SBR consists of semi-permanent early-successional habitat (Hunter et al 1999).

 

Bird populations associated with early successional habitats are in decline throughout the Southeast. The highest priority species within the SBR are the golden-winged warbler and Appalachian Bewick’s wren. The SBR is the only area of the southeast that golden-winged warblers can be found. It is a habitat specialist that uses high-elevation, early successional shrub-scrub mixed with grass (Hamel 1992). The decline of Bewick’s Wren is likely related to similar changes in landscape patterns. Field sparrows, northern bobwhite, ruffed grouse, chestnut-sided and prairie warblers have declined in many areas in recent years from their mid-century population peaks. Little is known about birds that inhabit mountain bogs, but in the historic conditions when wetlands were found throughout the Southern Appalachians, they provided semi-permanent habitat for early successional bird species.  However, past land use practices, increasing development pressures and the disruption of normal hydrologic processes have resulted in substantial loss of these habitats. The effects of these losses on birdpopulations are not well understood.