Virginia and Yellow Rail autumn migration ecology: Synthesis using multiple data sets

Abstract

Virginia and Yellow Rails are among the least studied birds in North America, and there is a specific lack of information about their autumn migration ecology and migratory habitat use. We conducted nocturnal surveys across 11 public wetlands in Missouri, USA from 2012-2016, and compared the timing of autumn migration from our surveys with three opportunistic datasets: 1) eBird records, 2) building strikes, and 3) state ornithological records. The observed timing (start and end date and duration) of Virginia Rail autumn migration varied between the opportunistic data and our surveys. Virginia Rail opportunistic data were bimodal, while our surveys had a single peak the second week in October. Yellow Rail autumn migration through Missouri peaked earlier in our surveys than opportunistic datasets which peaked during the second week in October. Both rails were found in moist soil habitats, however Virginia Rails selected perennial vegetation more than was available, while Yellow Rails selected annual plant species. Both species showed no selection for water depth and used shallow flooded wetlands. Understanding the autumn migration period and habitat requirements will allow wetland managers to better manage lands for autumn migrating Virginia and Yellow Rails.