Fall movements patterns of adult female American woodcock (Scolopax minor) in the western Great Lakes region

In 2002 and 2003, I collected movement and habitat data for 58 adult female woodcock during fall across 3 pairs of study sites in Minnesota, Wisconsin, and Michigan. Distances between subsequent daily locations were highly variable (C.V. = 2.188), and the majority (90.9%) of distances between subsequent daily locations of woodcock were 500 m) and forage in new areas when environmental conditions were not favorable, such as in the case of low earthworm abundance (biomass). Large movements into new foraging areas were correlated with the interaction between soil porosity and rainfall, presumably because earthworm availability increased following precipitation. Woodcock were also more likely to make longer movements in warmer temperatures with >2/3 of movements >500 m occurring when the daily low temperature was above the median low temperature of 2.4º C. My results suggest that the primary determinants of woodcock movements during fall (prior to migration) were low local food availability and the potential for increased food availability elsewhere. Longer movements were influenced by weather conditions, and there was little evidence that predator avoidance influenced movements between subsequent days. Adult female woodcock appear to incorporate prior knowledge of previously used areas into the decision of foraging location on a particular day, and generally return to the previous day’s foraging area unless conditions become more favorable elsewhere