Growth rates and energy demands in captive juvenile arctic foxes Alopex lagopus in Svalbard

Abstract

Four arctic fox Alopex lagopus pups (two males and two females) were caught at dens when about 25–53 days old and kept in outdoor pens at NyÅlesund, Svalbard. Their growth in body size (as measured by the length of a front foot), increase in weight, and food consumption were monitored from July to December, 1987. The pups grew rapidly and reached 97.5 ± 0.1% of their maximum adult size when they were 99–127 days old. Increase in body weight took longer (130 days). Food consumption generally increased until about 90 days old, after which it was highly variable. Pups consumed on average 266 kcal kg⁻¹ day⁻¹ growing 34g/day until 95 days old. Subsequently, until about 200 days old, they consumed 202 kcal kg⁻¹ day⁻¹ and grew 6.8 g/day.