A human-induced landscape of fear influences foraging behavior of brown bears

Abstract

Animals adapt their foraging behavior to variations in food availability and predation risk. In Sweden, brown bears (Ursus arctos) depend on a nearly continuous intake of berries, especially bilberries (Vaccinium myrtillus) during late summer and early autumn to fatten up prior to hibernation. This overlaps with the bear hunting season that starts on 21 August. Bilberry occurrence varies across space, as does human-induced mortality risk. Here, we hypothesize that brown bears select for areas with a high probability of bilberry occurrence across a boreal forest ecosystem in Sweden (H1), and that human-induced mortality risk reduces bear selection for bilberries (H2). In addition, we hypothesized that bears that survived the hunting season avoided bilberry areas associated with high risk, whereas bears that were later killed selected more strongly for berries and less against risk prior to the hunting season (H3). To evaluate our hypotheses, we used resource selection functions to contrast bear GPS relocation data (N = 35, 2012-2015) and random positions within the bears´ home range with generalized linear mixed effect models against two focal variables: a map predicting bilberry occurrence and a map predicting human-induced mortality risk. We found that bears selected for areas with a high probability of bilberry occurrence (supporting H1), but avoided these areas if they were associated with and high risk of hunting mortality (supporting H2). The killed and surviving bears did not differ in their selection for bilberries, but they did differ in their selection against risk (partially supporting H3). Surviving bears strongly avoided high risk areas, whereas killed bears responded less to risk and selected for high-risk areas with a low probability of bilberry occurrence. This suggests that killed bears selected for other food sources than berries in high risk areas, which exposed them to human hunters. We conclude that bears respond to a landscape of fear during the berry season and that different foraging strategies may have a direct impact on individual mortality during the hunting season.

The good, the bad and the ugly of COVID-19 lockdown effects on wildlife conservation: Insights from the first European locked down country

“…These findings suggest that rapid large-scale decreases in human disturbance have led to rapid changes in the human-induced landscape of fear ( Bleicher, 2017 ; Lodberg-Holm et al, 2019 ) generated by human infrastructures, activities and widespread presence, with animals showing up in unusual places that are normally perceived as too dangerous. A similar effect could potentially explain the increase in daily activity of animals that are normally active during the night or at twilight.…”

Denning in brown bears

“…If these changes are less predictable, we lack information on how bears might adapt to these year-to-year fluctuations. Because (a) early den exit by females with cubs may have repercussions on the health of cubs (Bellemain et al, 2006;Hertel et al, 2018; and (b) den abandonment of pregnant females increases probability of cub mortality (Swenson et al, 1997), (1) the autumn hunting season should end early enough so as to avoid disturbing female bears that have already denned or are showing predenning behavior (Friebe et al, 2001;Lodberg-Holm et al, 2019), and (2) winter-early spring human activities should be minimized near suitable or traditional denning sites (Linnell et al, 2000).…”

Coexistence with Bears in Romania: A Local Community Perspective

“…Instead, they would stimulate bears to try finding a way around to access the rich food sources provided by human settlements and crops. The goal of making bears wary of humans cannot be attained through strict protection but requires creating or re-creating the "landscape of fear" [14][15][16] for bears. The active management (sustainable hunting) practiced in the past seems to have been efficient not only in maintaining and even increasing bear populations [13,36] but also in making bears avoid humans, as shown in other parts of Europe where vigorous bear populations are still present [43,44].…”

“…Additionally, the relatively recent policy changes, which completely restricted any active management that has been keeping bear density under control through sustainable hunting, has produced an increase in bear density inside their former habitat area and also expansion into new areas. Moreover, banning of lethal control based management has also caused a reduction in what is called "the landscape of fear" [14] where animals avoid areas with higher risks of predation [15,16] and, thus, has favored more frequent conflicts with humans (damage on goods or attacks on people). Therefore, passive management seems to increase both the direct tangible costs (direct damage affecting some dwellers) and the intangible costs associated with wildlife (such as fear, danger, or risk affecting a greater number of dwellers).…”