Vocalization activity of breeding shorebirds: documentation of its seasonal decline and applications for breeding bird surveys

Abstract

We documented vocalization activity of breeding shorebirds at two sites in northern and western Alaska, on the Colville River Delta and on the Yukon – Kuskokwim Delta. At both sites, number of calling individuals decreased throughout the season. Variation in vocalization activity was significantly higher at the Colville River Delta towards the end of the season, while weather variables affected vocalization activity only on the Yukon – Kuskokwim Delta. Our results highlight the importance of timing, weather, and site-specific attributes on number of birds detected. We discuss our findings in the context of different methods to monitor breeding shorebirds.