Importance of an urban pine barrens for the conservation of early-successional shrubland birds

摘要

Shrubland birds have become one of the most conservation-reliant avian groups in the Northeastern United States. Their contemporary distribution is restricted to regenerating commercial forests, utility rights-of-way, and other types of managed early-successional habitat. This study explored whether a highly fragmented urban pine barrens can have conservation value for shrubland birds. Specifically, we estimated the amount of core early-successional habitat available to shrubland birds in the Albany Pine Bush Preserve (East-central New York State) and quantified bird-habitat associations from systematic point count surveys. This 1255 ha urban preserve contains approximately 150 ha of core early-successional habitat dominated by pitch pine and scrub oaks. Eighty-two species, including 24 shrubland birds, were observed in one breeding season. Many of these birds have shown regional population declines and six are species of greatest conservation need in New York. Two shrubland species previously extirpated were common across the preserve, and on average shrubland species were similarly abundant to non-shrubland species. Several shrubland species were strongly associated with the limited early-successional habitat, and the prairie warbler is recommended as the best potential avian indicator for monitoring ecosystem health and management effectiveness in this globally rare pine barrens. Twenty years of ecosystem restoration, including prescribed fire and invasive plant management, is buffering the effects of fire suppression, habitat loss, and fragmentation on shrubland birds in this landscape. When managed appropriately, urban shrublands can provide suitable breeding habitat and may aid in the regional conservation of early-successional shrubland birds.