Selectivity of Eurasian lynx Lynx lynx and recreational hunters for age, sex and body condition in roe deer Capreolus capreolus

摘要

Data on the age, sex and condition of roe deer Capreolus capreolus killed by Eurasian lynx Lynx lynx and human hunters were collected in two study areas in the counties of Nord-Trondelag and Hedmark in central and southeastern Norway, respectively. Data on the age and sex structure of the standing population were also collected. No differences in the age or sex structure of roe deer killed by lynx were found between the two study areas or between years with differing snow depths which was expected to affect age-class vulnerability. The profile of 151 lynx-killed roe deer (24% adult males, 44% adult females, 11% male fawns and 21% female fawns) was not statistically different from that of the standing population. In contrast, hunters killed a significantly larger proportion of adult animals, especially males (44% adult males, 28% adult females, 15% male fawns and 13% female fawns). The detailed age structure of lynx killed and hunter killed animals was not different within the adult age class. The body condition of roe deer declined during late winter (more so for males than for females), however, there was no difference in the condition of roe deer killed by lynx or hunters during early winter (the hunting season ends on 24 December). The overall picture is typical of a stalking predator that has few options to select individuals based on condition, age or sex in a prey species with no sexual dimorphism and which is relatively small in relation to the size of the predator (lynx are 50-70% the size of an adult roe deer). Human hunters, on the other hand, are clearly harvesting a non-random section of the population. The result is that hunting does not replicate natural predation, although lynx predation is likely to have a higher per capita impact on roe deer growth rates.