Supplemental food from anthropogenic sources is a source of conflict with humans for many wildlife species. Food-seeking behaviours by black bears Ursus americanus and brown bears Ursus arctos can lead to property damage, human injury and mortality of the offending bears. Such conflicts are a well-known conservation management issue wherever people live in bear habitats. In contrast, the use of anthropogenic foods by the polar bear Ursus maritimus is less common historically but is a growing conservation and management issue across the Arctic. Here we present six case studies that illustrate how negative food-related interactions between humans and polar bears can become either chronic or ephemeral and unpredictable. Our examination suggests that attractants are an increasing problem, exacerbated by climate change-driven sea-ice losses that cause increased use of terrestrial habitats by bears. Growing human populations and increased human visitation increase the likelihood of human–polar bear conflict. Efforts to reduce food conditioning in polar bears include attractant management, proactive planning and adequate resources for northern communities to reduce conflicts and improve human safety. Permanent removal of unsecured sources of nutrition, to reduce food conditioning, should begin immediately at the local level as this will help to reduce polar bear mortality.

Polar bears Ursus maritimus have a circumpolar distribution that is directly tied to the Arctic sea ice. Although they are wide-ranging, polar bears do not belong to a single population but rather are comprised of 19 largely discrete subpopulations, 13 of which are fully or partly under Canadian jurisdiction. These subpopulations are used to manage the sustainable harvest of polar bears in Canada but for conservation purposes the species is currently considered a single biological unit. Long-term climate warming has reduced the availability of sea ice that polar bears require for feeding, movement and reproduction, and continued declines in ice extent and duration are forecast to have significant negative effects on polar bears in some areas. Under the Canadian Species at Risk Act separate legal protection may be given to intraspecific groups (so called designatable units, DUs) that are genetically, geographically and/or biogeographically distinct. We examined the conservation status of polar bears across their Canadian range and compared large-scale ecosystem properties across subpopulations. We found that threats to the conservation of polar bears are not spatially uniform and we identified five DUs that captured broad patterns of polar bear biodiversity. We conclude that the use of DUs provides a biologically-sound framework for the conservation of polar bears.

A case of polar bear infanticide and cannibalism is reported from Phippsøya, Svalbard. In this instance, a cub of some 7 months was killed by an adult male bear, which was in poor condition, in the close proximity of the mother, which was also in poor condition. It seems probable that the attack was made for nutritional gain.