Pattern of δ13C and δ15N in wolverine Gulo gulo tissues from the rooks Range, Alaska

Abstract

Knowledge of carnivore diets is essential to understand how carnivore populations respond demographically to variations in prey abundance. Analysis of stable is a useful complement to traditional methods of analyzing carnivore diets. We used data on δ13C and δ15N in wolverine tissues to investigate patterns of seasonal and annual diet variation in a wolverine Gulo gulo population in the western Brooks Range, Alaska, USA. The stable isotope ratios in wolverine tissues generally reflected that of terrestrial carnivores, corroborating previous diet studies on wolverines. We also found in variation in δ13C and δ15N both between muscle samples collected over several years as well as between tissues with different assimilation rates, even after correcting for isotopic fractionation. This suggests both annual and seasonal diet variation. Our results indicate that data on δ13C and δ15N holds promise for qualitative assessments of wolverine diets changes over time. Such temporal variation may be important temporal change in diets of wolverines and similar carnivores.