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.

Harvest by means of hunting is a commonly used tool in large carnivore management. To evaluate the effects of harvest on populations, managers usually focus on numerical or immediate direct demographic effects of harvest mortality on a population's size and growth. However, we suggest that managers should also give consideration to indirect and potential evolutionary effects of hunting, e.g., the consequences of a change in the age, sex, and social structure, and their effects on population growth rate. We define "indirect effects" as hunting-induced changes in a population, including human-induced selection, that result in an additive change to the population growth rate "lambda" beyond that due to the initial offtake from direct mortality. We considered four major sources of possible indirect effects from hunting of bears; 1) changes to a population's age and sex structure, 2) changes to a population's social structure, 3) changes in individual behavior, and 4) human-induced selection. We identified empirically supported, as well as expected, indirect effects of hunting, based primarily on > 30 years of research on the Scandinavian brown bear population. We stress that some indirect effects have been documented, e.g., habitat use and daily activity patterns of bears change when hunting seasons start and changes in male social structure induces sexually-selected infanticide and reduces population growth. Other effects may be more difficult to document and quantify in wild bear populations, e.g., how a younger age structure in males may lead to decreased offspring survival. We suggest that managers of bear and other large carnivore populations apply the cautionary principle and assume that indirect effects do exist, have a potential impact on population structure, and, ultimately, may have an effect on population growth that differs from that predicted by harvest models based on direct effects alone.

Summary The removal of individuals through hunting can destabilize social structure, potentially affecting population dynamics. Although previous studies have shown that hunting can indirectly reduce juvenile survival through increased sexually selected infanticide (SSI), very little is known about the spatiotemporal effects of male hunting on juvenile survival.Using detailed individual monitoring of a hunted population of brown bears (Ursus arctos) in Sweden (1991–2011), we assessed the spatiotemporal effect of male removal on cub survival.We modelled cub survival before, during and after the mating season. We used three proxies to evaluate spatial and temporal variation in male turnover; distance and timing of the closest male killed and number of males that died around a female's home range centre.Male removal decreased cub survival only during the mating season, as expected in seasonal breeders with SSI. Cub survival increased with distance to the closest male killed within the previous 1·5 years, and it was lower when the closest male killed was removed 1·5 instead of 0·5 year earlier. We did not detect an effect of the number of males killed.Our results support the hypothesis that social restructuring due to hunting can reduce recruitment and suggest that the distribution of the male deaths might be more important than the overall number of males that die. As the removal of individuals through hunting is typically not homogenously distributed across the landscape, spatial heterogeneity in hunting pressure may cause source–sink dynamics, with lower recruitment in areas of high human‐induced mortality.