The Effects of Hunting on the
Population, Behavior, and Evolution

An overview of hunting in Scandinavia

Bears in Scandinavia are subject to hunting. Sweden and Norway have established legal license hunts and allow for ‘protection’ hunts where people may target specific problem bears or bears in specific areas outside of the normal hunting season. In Sweden, the number of bears harvested is set by the county authorities for each county after delegation from the Swedish Environmental Protection Agency. The quotas are thus set on county level, and often further divided into hunting zones within the counties, in accordance with the management goals and plans decided in the respective county's "wildlife delegation" (1). These delegations are generally comprised of stakeholders, including local politicians, landowners, and other interested parties such as reindeer herding representatives in those counties where reindeer herding occurs. The wildlife delegation therefore has an indirect way of affecting the hunting quotas as these are set to reach the overall management goals within the county. In Sweden, bear hunting is allowed between 21 August and 15 October (30 September in parts of Norrbotten), with a few exceptions when the hunting period may end earlier if the quota is filled. The hunt is open to all hunters that have the pre-requisite license, paid the hunting permit fee, and has appropriate firearm, and hunters may harvest as many bears as they wish within the quota limits. However, hunters must report harvested bears to the appropriate authorities within 1 hour; unrecovered shot bears must also be reported and are similarly deducted from the quota if not considered unharmed. Hunting with dogs is permitted, and baiting for hunting purposes is allowed; baiting was banned in 2001 then reinstated again in 2013 (1). Hunters are only allowed to harvest solitary bears; females with any aged cubs, or family groups, are protected during the hunt. Nation-wide quotas have shifted through time, depending on management goals and strategies. There is little evidence for illegal harvest of bears in Sweden, or poaching, especially in northern Sweden. However, this is difficult to monitor and has thus never been quantified (2). Harvest quotas have increased drastically in recent years. In 2018 the harvest was 288 bears while for 2023 the harvest was 648 bears with a distribution of 55% females and 45% males (3). In addition to these license hunts there are bears removed in protective hunts during spring.

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Bear hunting in Norway is different than in Sweden. Norway has eight large predator management regions, each with its own large predator management plan. The plans are reflective of the overarching goals set for the region, and designate areas prioritized for large predators as well as areas prioritized for free-range grazing livestock. There is a national goal of 13 yearly reproductions as well as regional goals, that differs between regions. When the population goal is reached in a region, the setting of quotas is moved from the Norwegian Environmental Agency to the regional management authority. Regions without a population goal can also decide on license hunts. In Norway, protected hunts are allowed between 1 June and 15 October and license hunting is allowed between 21 August and 15 October. Females with accompanying cubs are protected in the license hunt. Hunting with dogs is permitted, but hunting with bait is strictly prohibited. Hunters need to register as bear hunters in the national hunter registry. Norway’s bear population is much smaller than Sweden, and thus there are fewer hunts here. 

What bears are harvested and how

Bears are harvested by both bear hunters, or those who are in the forest with the specific aim of hunting bears, and opportunistically by moose hunters as well. Between 1981 and 2004, bears were primarily hunted using dogs (37%), by still hunting (30%), by stalking (16%), or by baiting (18%) (4). During the years baiting was banned (2001-2012), hunting methods included dogs (71%), still hunting (21.5%), and stalking (7.5%) (2). The ban on bear baiting had no overall effect on general harvest patterns; the age and sex of killed bears remained the same (4). In general, there is relatively little difference in the age and sex of harvest bears with regards to the hunting method used (4). Bear hunters in Scandinavia are likely not selective when it comes to age and sex; the opportunity to encounter a bear comes so infrequently that hunters will likely attempt to harvest what they encounter (4). Young male bears are more likely to be harvest by hunters who use the sit and wait method, likely because those young males are the most mobile and therefore the most likely to be encountered (4).

Hunting and population dynamics

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Hunting is the primary driver of brown bear population dynamics in Scandinavia. Hunting bears directly decreases bear numbers in Scandinavia and is additive to natural sources of mortality (5). However, hunting also indirectly alters population dynamics by 1) shifting the age and sex structure of the population, 2) altering the social structure, 3) shifting individual bear behavior, and 4) selecting for certain life history or genetic traits (6-8). These indirect effects are important because changes in bear behavior and population structure can alter the survival and reproductive patterns of the population, creating a feedback loop from hunting that continues after offtake has occurred (6-8).

Population growth rate: Bear population growth rate is primarily driven by the presence and success of reproductive females, i.e., population growth is highest when there are many females who produce multiple cubs that survive to adulthood (8, 9). Thus, protecting females with cubs is a key way to increase population growth (9). For example, the protection of family groups may lead to an increased protection of those females that keep their cubs an extra year (to 2 ½) compared to other females, which may ultimately lengthen litter interval, lower individual reproductive potential, and decrease population growth rate (10). Furthermore, protecting family groups also decreases the population of bears that can potentially be hunted, which increases hunting pressure on solitary bears (9). This may contribute to a decrease in population growth rate if the number of male bears on the landscape becomes too few, or the male population is kept at a young age (9). Functionally all population demographic rates (i.e., the survival of females and cubs and the reproductive output of all age classes of females) are affected by hunting which ultimately contributes to decreased population growth (8).

Age and sex structure: Hunter harvest also likely affects the age structure of the population, although this remains unquantified. A younger age structure in general may result in decreased reproductive success; first time mothers are less successful while prime-aged females are the most successful (11).

Hunting and bear behavior

Hunting activity peaks in the early hours of the day during the hunting season, which means risk from hunting is highest during that time, and lower during the other hours of the day (12). License hunted bears are more at risk when they are in close proximity to human infrastructure and activities such as roads and villages (13). Mortality risk from management removals is highest for bears when they are near human infrastructure such as settlements, buildings, roads, and on agricultural land (13). Management bears were killed in closer proximity to human infrastructure (13).

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Activity patterns and movement: Bears in Scandinavia alter their movement and activity patterns in response to hunting pressure (14, 15). For example, bears that experience hunting pressure, i.e., solitary males and females, begin to move more during non-daylight hours once the hunting season starts (14, 15). Family groups that are not hunted also shift their movement patterns in a similar way, but to a much lesser extent (14). Bears also respond directly to hunting itself. A recent study that explored the effect of simulated hunts (with dogs) on bear behavior and stress found that bears traveled longer distances at higher speeds after an encounter with a hunting team (16). Furthermore, hunted bears also appeared to go through more acute stress, showing increased heart rates and body temperatures directly after a hunting encounter (16).

Foraging Behavior: Altered movement patterns often translate into altered foraging behavior during the fall hunting season. Bears respond to temporal risk (i.e., risk is greater during the daytime) by foraging less during the morning hours in the hunting season (i.e., they move less in general during this time), and they forage less effectively and on poorer quality berries during that time (12). They decreased their foraging activity, their food intake, and they ate poorer quality foods during this time (12). Furthermore, their chosen foraging strategy may expose them to more or less risk during this time period, i.e., bears that forage in risky places are more likely to be shot (17). In general, bears select for areas where blueberries are more likely to occur, but will avoid these areas during the hunting season if they are high risk, meaning they are more likely to be shot there (17). This results in a food for safety trade-off where bears limit their chances of being shot by foraging in areas that are safer but less productive (17). This is important because fall is a critical time of the year for bears, when they enter into hyperphagia and eat profusely to prepare for the denning season. Altered movement and foraging patterns during fall may affect their ability to gain fat before denning, which can affect their body condition in spring as well as their reproductive success (12, 14).

Mating and reproduction: Increased sexually selected infanticide is another indirect effect of bear hunting in Scandinavia (18, 19). Males only kill cubs that aren’t their own. Removing males from an area increases the chance that new males will move, which increases the potential for cubs to be killed. For example, females with home ranges in proximity to male bear harvest locations within the previous 1.5 years have an increased risk of cub loss (18). The subsequent effects of infanticide in the population mean that harvesting one adult male is the equivalent of removing between ½ to 1 female bear from the population (19).

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Social behavior: The underlying social structure of the bear population in Scandinavia is likely altered via hunter harvest. For example, female survival is lower when harvest rates are high, which can result in a breakdown of the matrilineal partially territorial structure of the bear population in Scandinavia (20). When bears are shot it creates ‘home range vacancies’ in the landscape that may then be filled in by other dispersing bears (21). Thus, hunter harvest changes the competitive landscape that would otherwise exist, releasing bears from competition with one another. Bears of the same sex as those that were harvested use the harvested home range of the bear more after they have been shot (21). Interestingly, surviving males who were less related to the harvested bear were more likely to use his previous home range (21). Females still stay close to home and use home ranges of related females, regardless of whether they have been shot or not (21).

Human-induced selection of traits

Hunters also tend to select for certain behaviors in bears, which might alter the trend of behaviors within the population (22). For example, research suggests that hunters tend to shoot males that move less in general and are less active during legal hunting hours, and shot both males and females that were closer to roads, which may select for boldness traits (22). A study on reproduction effort in relation to the body weight of brown bears under intense harvest pressure in 1) areas with long-term (>500 years) harvest with 2) areas with a shorter period (<50 years) of harvest found that there is greater reproductive effort in populations with long-term intense harvest pressure (2). Thus, hunting the bear population in Scandinavia could result in a life history shift within the population whereby bears will begin to reproduce at a younger age and at a lower body weight, i.e., prioritizing reproduction over body growth.

What it all means:

Hunting pressure clearly plays a key role in the Scandinavian bear population, affecting everything from their behavioral patterns to their population demography (6). This occurs both directly through hunter harvest but also indirectly by altering the age and sex structure of the population as well as their social interactions and behavior. Furthermore, hunting bears likely diminishes their ecological role as predators within the ecosystem, indirectly affecting other species (23). It is our view that the indirect effects of hunting on the bear population in Scandinavia deserve more attention by researchers and managers as they can influence population growth rates in unexpected ways (6).