Distribution and Abundance of King and Clapper Rails on the Delmarva Penninsula

King (Rallus elegans) and Clapper (Rallus crepitans) rails co-occur in marshes on the Delmarva Peninsula with King Rails restricted to brackish and fresh-tidal marshes and Clapper Rails occurring in marshes with greater salinity. Our understanding of the distribution and abundance for these two species is limited and King Rail populations have declined across their entire range in recent years. The marshes of the Mid-Atlantic have historically supported King Rails, however, surveys conducted in 2002 found a marked decrease in the number of sites occupied and estimated abundance in the Chesapeake Bay. It was therefore our goal in this project to use standardized protocols to sample historic known King Rail sites and new marshes to evaluate King and Clapper rail populations in the Delmarva Peninsula in 2014 and 2015. We used the same two-stage cluster sampling employed by the Saltmarsh Habitat and Avian Research Program (SHARP; www.tidalmarshbirds.org) to randomly select 40 km2 hexagons (primary sampling units) in tidal fresh and brackish marshes of the northern Chesapeake and Delaware Bays and randomly located sampling points within each hexagon (secondary sampling units).