Age ratios, sex ratios, and a population estimate of Yellow Rails at San Bernard National Wildlife Refuge, Texas

• DOI: 10.1894/mcg-02.1
• Publication Date: 2015-03-17T15:39:29Z
• Authors: Christopher J. Bu...; Jennifer K. Wilson; Charles R. Brower; Stephen R. Frazee
• Keywords: Wildlife refuge; Sexing; Mark and recapture

Yellow rails (Coturnicops noveboracensis) winter along the U.S. coast, from North Carolina to Texas and southeastern Oklahoma. Although this rail is listed as a species of special concern in most provinces states where it breeds, little known about ecology or population sizes secretive species. The goals our study were approximate numbers determine age sex ratios yellow wintering selected marshes at San Bernard National Wildlife Refuge (San NWR) Brazoria Matagorda counties, Texas. banded Spartina November 2009–April 2010. Feather samples collected each for use DNA sexing. We captured 170 Cedar Lake Creek Unit NWR recaptured 17 over course study. estimated that we sampled (224.6 ha) late through mid-April consisted 1,170 ± 300 individuals, 5.2 1.3 rails/ha. highest ranked POPAN models suggest probability recapture entering both time-dependent, while survival was time-independent. All prior January (n = 17) could be aged, with six (35.2%) aged HY (Hatch Year), 11 (64.7%) AHY (After Hatch Year). However, unable conclusively assign ages April. Sufficient obtained 59 33 (55.9%) male. While range widespread, likely coastal prairies are particularly important given large high density encountered during