Assessment of Techniques for Evaluating American Woodcock Population Response to Best Management Practices Applied at the Demonstration-Area Scale (RWO 91 Annual Report, 2012)

Abstract

American woodcock (Scolopax minor) have experienced significant long-term declines in the Eastern and Central Management Regions since Singing-ground Surveys (SGS) were first implemented in the mid-1960s. Declines in population trend coupled with declines in woodcock recruitment (indexed through immature:adult female ratios derived from wingcollection surveys) are widely believed to be caused by the loss or alteration of early succession forest and shrubland land-cover types throughout the breeding range. Developing a system of demonstrations areas (≈200 – 800 ha) where specific Best Management Practices (BMPs) are applied throughout the woodcock breeding range is one strategy to influence landscape change and potentially increase woodcock populations. However, how woodcock populations respond to BMPs applied at the demonstration-area scale is not well documented. To evaluate woodcock response to BMPs, we are assessing four population-level metrics at Tamarac National Wildlife Refuge (NWR) in northwest Minnesota: displaying male abundance, female habitat use, female survival, and recruitment of juveniles. During the 2011 and 2012 field seasons we captured a total of 529 woodcock, including 41 (2011: n = 23, 2012: n = 18) adult female woodcock that we radio-marked. We found 50 nests (2011: n = 27, 2012: n = 23) and monitored 52 woodcock broods (2011: n = 30, 2012: n = 22). In 2011, abundance of displaying males was similar at Tamarac NWR to abundance in adjacent, reference areas, but in 2012 Tamarac NWR had higher abundance than adjacent areas. In both years, breeding females and broods used dense vegetation in managed areas.