DIGITAL PLAYBACK AND IMPROVED TRAP DESIGN ENHANCES CAPTURE OF MIGRANTSORAS AND VIRGINIA RAILS

We used playback of rail vocalizations and improved trap design to enh ance capture of fall migrant Soras (Porzana carolina) and Virginia Rai ls (Rallus limicola) in marshes bordering the tidal Patuxent River, Ma ryland. Custom-fabricated microchip message-repeating sound systems pr ovided digitally recorded sound for long-life, high-quality playback. A single sound system accompanied each 30-45-m long drift fence trap l ine fitted with 1-3 cloverleaf traps. Ramped funnel entrances improved retention of captured rails and deterred raccoon (Procyon lotor) pred ation. Use of playback and improved trap design increased trap success by over an order of magnitude and resulted in capture and banding of 2315 Soras and 276 Virginia Rails during September and October 1993-19 97. The Sera captures more than doubled the banding records for the sp ecies in North America. This capture success demonstrates the efficacy of banding large numbers of Soras and Virginia Rails on migration and winter concentration areas.