The relative importance of direct and indirect effects of hunting mortality on the population dynamics of brown bears.
There is increasing evidence of indirect effects of hunting on populations. In species with sexually selected infanticide (SSI), hunting may decrease juvenile survival by increasing male turnover. We aimed to evaluate the relative importance of direct and indirect effects of hunting via SSI on the population dynamics of the Scandinavian brown bear (Ursus arctos). We performed prospective and retrospective demographic perturbation analyses for periods with low and high hunting pressures. All demographic rates, except yearling survival, were lower under high hunting pressure, which led to a decline in population growth under high hunting pressure (λ = 0.975; 95% CI = 0.914-1.011). Hunting had negative indirect effects on the population through an increase in SSI, which lowered cub survival and possibly also fecundity rates. Our study suggests that SSI could explain 13.6% of the variation in population growth. Hunting also affected the relative importance of survival and fecundity of adult females for population growth, with fecundity being more important under low hunting pressure and survival more important under high hunting pressure. Our study sheds light on the importance of direct and indirect effects of hunting on population dynamics, and supports the contention that hunting can have indirect negative effects on populations through SSI.
Département de biologie, Université de Sherbrooke, 2500 boulevard de l'Université, Sherbrooke, Quebec, Canada J1K 2R1 jacinthe.gosselin2@usherbrooke.ca.
Jacinthe
http://orcid.org/0000-0002-0161-1343
J
Gosselin
Department of Environmental and Health Studies, Telemark University College, Bø 3800, Norway Institute of Wildlife Biology and Game Management, University of Natural Resources and Life Sciences, Vienna 1180, Austria.
Andreas
A
Zedrosser
Department of Ecology and Natural Resource Management, Norwegian University of Life Sciences, Ås 1432, Norway Norwegian Institute for Nature Research, Trondheim 7485, Norway.
Jon E
JE
Swenson
Département de biologie, Université de Sherbrooke, 2500 boulevard de l'Université, Sherbrooke, Quebec, Canada J1K 2R1.
Fanie
F
Pelletier
D000818:Animals; D003247:Conservation of Natural Resources; D003710:Demography; D005260:Female; D008136:Longevity; D008297:Male; D011157:Population Dynamics; D011446:Prospective Studies; D012189:Retrospective Studies; D013548:Sweden; D001503:Ursidae / Q000502:physiology*
behaviour; brown bear; carnivore; harvesting; population dynamics; sexually selected infanticide