Summary of Fall Passerine Banding on the Eastern Shore of Virginia National Wildlife Refuge: 2009-2010 Seasons
Abstract
Along the Atlantic Coast, significant barriers such as large bodies of water act as migration bottlenecks funneling large numbers of birds onto relatively small land masses. For southbound migrants, the Chesapeake Bay is one of the largest physical barriers along the East Coast of North America. Migrants that reach the mouth of the Bay in the hours just before dawn land near the tip of the Delmarva Peninsula. Many of these birds depend on habitats found within the lower peninsula for rest and refueling before leaving on the next leg of their migration. Because of its unique geographic position, the lower Delmarva contains some of the most critical habitats for migrant birds within the Atlantic Flyway. The Eastern Shore of Virginia National Wildlife Refuge is particularly significant because of its position at the southern tip of the peninsula. Beginning in the fall of 2009, and continuing in the fall of 2010, the U.S. Fish and Wildlife Service initiated a study of shrubland migrants within a network of several refuges including the Eastern Shore of Virginia National Wildlife Refuge. The Eastern Shore Refuge is currently managing approximately 280 acres in an early successional grassland/shrub-scrub habitat. The primary goal of this study is to collect baseline data on the number and diversity of fall migrants using this habitat complex. The information will be used to better manage habitat for migrating songbirds on the lower Eastern Shore of Virginia. The study includes point counts, vegetation characterization work, and banding of migrant passerines. The Center for Conservation Biology partnered with the refuge to conduct field work during both fall seasons. In 2010, the songbird banding station was open for 83 days between August 31st and November 30th. In 2009, songbird banding was conducted on 57 days between 15 September and 30 November. A total of 11,638 birds were banded of 97 species in 2010, and 7,860 birds were banded of 85 species in 2009. Total captures included 4,634 (23.77%) Neotropical migrants, 14,643 (75.10%) temperate migrants, 218 (1.12%) resident birds, and 2 (0.01%) vagrant birds. Average capture rate was 175 birds/100 net hours in 2009 and 169 birds/100 net hours in 2010. Temporal distribution varied greatly within both seasons.
