Denning behaviour and activity of arctic fox Alopex lagopus pups: Implications of food availability

Summary The behaviour of arctic fox Alopex lagopus pups was studied in 51 in two regions of southern Scandinavia (60 and 63°N) and in 51 on the western coast of Svalbard (79°N). In Scandinavia, observations were made both in years of high and low abundance of food (i.e. voles and lemmings). No rodents live on the western coast of Svalbard, where foxes depend mainly on sea birds. Pups were on average lying nearly half the time, with explore and play fight next in frequency. Pups in a year of decreasing or low lemming abundance rested more outside the den, rested more overall, and less frequently indulged in exploration or play fighting than pups in years of higher abundance of voles and lemmings. They also began following adults at an early age and abandoned their natal den earlier. Svalbard pups were intermediate in several respects, but they regularly abandoned their natal den at the age of about 1 1/2 months. Pups at dens were active 24% of daytime hours (08.00–20.00) and 31% of nighttime hours (20.00–08.00).