FALL SURVIVAL, MOVEMENTS, AND HABITAT USE OF AMERICAN WOODCOCK IN THE WESTERN GREAT LAKES REGION: 2004 FIELD SEASON REPORT

Declines in the number of American woodcock (Scolopax minor) heard on annual singing ground surveys have resulted in concern regarding the population status of woodcock in both the Central and Eastern Management Regions. Although changes in the distribution and abundance of woodcock habitat are believed to largely be responsible for apparent population declines, relatively little is known regarding the influence of harvest on woodcock population dynamics. Similarly, movements and habitat use of woodcock in fall prior to migration are poorly understood. In 2001 (Minnesota) and 2002 (Michigan and Wisconsin), we initiated a study of woodcock to assess magnitude and causes of woodcock mortality, and investigate movements and habitat use of woodcock in the western Great Lakes Region during fall. In all 3 states, we radio-marked woodcock on paired study areas; one of which was open to woodcock hunting (“hunted areas”) and one of which was closed (“non-hunted areas”) to hunting or had limited access for hunting (“lightly-hunted areas”). From 2001-2004 across all 3 states we captured and radio-equipped 1,169 woodcock; 594 on hunted areas and 575 on non-hunted or lightly-hunted areas. Preliminary survival estimates during the hunting season ranged from 0.639 ± 0.150 (hunted area in Wisconsin in 2003) to 0.900 ± 0.228 (hunted area in Minnesota in 2001) and were generally higher in non-hunted than in hunted areas. However, survival estimates between study sites in the same state during the same year were not statistically different from one another, except in 2 instances. Survival was variable among years and sites, but highest in hunted areas, suggesting that hunting mortality may vary more than other causes of mortality. A sub-sample of after-hatch-year (AHY) female woodcock was monitored intensively in each state and analyses of movement and habitat use data from these birds suggest that woodcock make primarily small-scale movements (47.7%