Age and sex-specific variation in detectability of moose (Alces alces) during the hunting season: implications for population monitoring

作者:Solberg Erling Johan*; Rolandsen Christer M; Heim Morten; Linnell John D C; Herfindal Ivar; Saether Bernt Erik
来源:European Journal of Wildlife Research, 2010, 56(6): 871-881.
DOI:10.1007/s10344-010-0385-x

摘要

The sustainability of wild ungulate harvests can be greatly enhanced if monitoring data are available to permit an adaptive management approach. Utilising data provided by hunters is potentially the most cost-effective approach. In Scandinavia, observations recorded by moose (Alces alces) hunters provide a range of indices of population density, composition and reproductive performance. These are routinely used in practical management, but there are still many questions about their accuracy and precision. In this study, we availed of the fact that virtually all individual moose on the island of Vega in central Norway were marked during the period 1992-2005. Thus, we were able to compare the observation indices provided by hunters to the known size and composition of the population. The results indicate that the hunter observation indices provided accurate estimates of variation in moose cow recruitment and twinning rates. The estimates of sex ratio closely followed the pattern of annual variation but showed a consistent pattern of over-estimating the proportion of males. Thus, males seem to visually expose themselves more often for hunters than do females. The density index, measured as number of moose seen per hunter day did not to the same extent follow the variation in population density, possibly because moose were more naive in the first years after hunting was introduced or because of reduced detection conditions due to increasing scrub and tree encroachment during the study period. The results are discussed in light of their application to management and the evolutionary pressures in moose anti-predator behaviour.

  • 出版日期2010-12