Where is the refrigerator? A spatial approach to wolverine (Gulo gulo) food hoarding behavior in Scandinavia
MetadataShow full item record
Food hoarding helps animals to maintain their physical condition during times of food scarcity. Wolverines (Gulo gulo) inhabitat mostly environments of low productivity, and are known to hoard food for long-term periods, to store a single food item per food cache, and to spatially spread their food caches across their home range. Few studies have been dedicated to describing the wolverine’s food hoarding behavior. We identified 303 caches from 38 individuals in four study areas in Scandinavia, by exploring clusters of GPS positions during periods of four to eight weeks, in both summer and winter, with a total of 2090 monitoring days. During summer, it was easier to identify caches than in winter, when signs of caching activity are quickly covered up by snow. We studied the wolverine’s cache dispersion by means of a Complete Spatial Randomness test, identified their preferred caching habitat through resource selection modelling with conditional logistic regression, and applied linear mixed-effect models to study the caching distance between sources and caches. Wolverines hoarded food in both seasons and widely spaced their caches, occasionally clustering them in parts of their home range. Their optimal caching habitat was located in steep rugged terrain with plentiful vertical structure that offerered suitable micro-habitat. Wolverines did not cache further away from food sources to maximize cache habitat suitability. If a different carnivores species killed a prey animal, wolverines cached closer to a source. Ultimately the food hoarding behavior of wolverines is an adaptive response to survive periods of food scarcity.