Litter size, sex ratio, and age structure of gray wolves, Canis lupus, in relation to population fluctuations in northern Belarus

摘要: Gray wolf (Canis lupus L., 1758) population fluctuations in northern Belarus (Vitebsk region) between 1990 and 2003 were significantly affected by hunting pressure humans. Mean litter size was inversely density dependent varied from 4.8 to 7.7 pups (range 2–10). The increase with declining of concerned only female pups, whereas the number male a not related density. sex ratio significantly: proportion females reached 70% low-density declined 40%–50% high-density population. age structure also varied. In years following heavy pressure, 55% individuals shot juveniles <1 year old (with strong predominance that constituted 69% juveniles shot), 11% wolves older than 4 years. mean all 1.5 years. low 34% animals 20% exceeded 4 years...