Daily Weather Affects Body Condition, Sex, and Age Ratios of Harvested Dabbling Ducks in Texas

Duck activity patterns have anecdotally been associated with weather for thousands of years. However, these relationships have rarely been tested scientifically. We hypothesized that characteristics of wintering ducks harvested by hunters would be associated with daily weather conditions (precipitation, temperature, and wind speed), and specifically, that smaller-bodied ducks and those with poor body condition would be harvested less frequently in adverse weather conditions relative to 30-year daily normals. We evaluated these hypotheses using beta regression modeling and general linear models for five species of dabbling ducks: blue-winged teal (Spatula discors; n = 608), green-winged teal (Anas crecca; n = 518), northern shoveler (Spatula clypeata; n = 175), northern pintail (Anas acuta; n = 94), and gadwall (Mareca strepera; n = 206) harvested by hunters on the coastal Texas win- tering grounds (December 2017–January 2018 and November 2018–January 2019). We found that temperature did not affect age and species compo- sition of harvested ducks, but wind and precipitation did, with fewer small-bodied duck species generally being harvested in higher-than-average wind and precipitation and immature ducks harvested in significantly lower proportions at higher-than-average wind speed. Body condition of harvested ducks for all species was significantly related to temperature but was related to wind and precipitation for larger-bodied species only. Overall, our results provide strong support for our hypothesis that hunter harvest patterns are associated with daily weather but only mixed support for our prediction that weather predicts body size and condition of harvested ducks. These results can inform managers on hunter placement based on forecasted weather. In addition, as weather patterns are expected to become less predictable due to global climate change, understanding responses of duck hunter harvest to daily weather fluctuations becomes more important for informing management.

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