Short-term behavioural response of polar bears (Ursus maritimus) to snowmobile disturbance
In this study the distance, at which polar bears detected and actively responded to approaching snowmobiles was measured and the behavioural response was recorded. The study was performed on Svalbard, an arctic island where human traffic has increased substantially in recent years. Fieldwork was conduced in April and/or May during the years 2003–2005. Polar bears […]
Determinants of Home Range Size for Polar Bears (Ursus maritimus)
The mean home range size of female polar bears (Ursus maritimus; 125 100 km2 ± 11 800; n = 93) is substantially larger than the predicted value (514 km2) for a terrestrial carnivore of similar weight. To understand this difference, we correlated home range size and sea ice characteristics. Home range size was related to […]
Vitamin D content in Alaskan Arctic zooplankton, fishes, and marine mammals
Abstract 10.1002/zoo.10104.abs We postulated that dietary ingestion of vitamin D may be used by some Alaskan Arctic marine mammal species in addition to, or instead of, cutaneous production to meet nutritional requirements. Zooplankton (n=5) sampled near Kaktovik, Alaska, contained no measurable vitamin D2 or D3, but did contain provitamin D (7-dehydrocholesterol), the cutaneous precursor for […]