Body composition of three polar bear (Ursus maritimus) cubs found dead at Svalbard

We determined the body composition from the carcasses of three 3- to 4-mont hs-old polar bear cubs found dead at Svalbard, Norway. Two of the cubs were killed by a male bear at the den and one cub died from starvation. These t hree carcasses weighed 70-77% of total body mass of cubs. The ash and prote in content of the three carcasses were similar but the starving cub had hig her water content and lower fat content than the two killed cubs. The fat c ontent varied from 1.3% (starving cub) to 12.9% while the content of water and fat was similar (about 76%) in the three cubs. More data on the body co mposition of polar bear cubs at time of emergence from the den are needed t o understand the breeding ecology and reproductive energetics of female pol ar bears.