Soil nutrients and deer density affect antler size of the Carpathian red deer

Size of antlers in polygynous male cervids is a result of their genetic potential and nutrition and is believed to be a reliable indicator of males' fitness and habitat quality. We used data on antler size of 1390 red deer males harvested during hunting seasons 2014/2015-2018/2019 in Slovakia to test the hypothesis that spatial variation in the size of antlers, including number of tines, mass and length of antlers, is related to environmental conditions such as availability of calcium, phosphorus and nitrogen in soils and deer density. We found that overall hunting value of antlers including number of tines, mass and length of antlers were higher in areas with higher availability of the CaCO3, P and N in soils. Moreover, we found no signs of decline in the overall score and in number of tines when availability of CaCO3 was high, in the length of antler when availability of P was high, and in the antler mass when availability of N was high. Deer density had negative effect on the antler size including the number of tines and antler length and had no effect on the onset of the peak and rate of decline except for the antler mass. Understanding the extent to which environment influences antler size in cervids is important to develop structured and region-specific policies.