New World’s Four Species of Bear

All Suffer Habitat Loss. Two are Considered Vulnerable to Extinction

Jan 4, 2008

Although New World bears are not facing as many threats as Asian bears, it is important that sufficient habitat be maintained. Climate change threatens polar bears.

In the New World there are four species of bear, three in the northern hemisphere and one in the southern hemisphere. All are facing habitat loss and fragmentation as human populations increase. In North America, trade in bear gall bladders and claws has caused an increase in poaching, especially for the black bear. In South America, expanding agriculture is creating habitat loss which results in conflict with humans for the spectacled bear.

This black bear’s historic range covered most of Canada, the US and northern Mexico. Although it has been extirpated from some areas, present population is estimated at 850,000 to 950,000. This population is healthy but threats to the species include habitat loss with the resultant potential for conflict with humans and, more recently, poaching for the Traditional Chinese Medicine trade. It is listed as Least Concern by the IUCN

The only living species of bear in South America, the Spectacled bear is considered Vulnerable by the IUCN. It is found from Venezuela to Argentina along the Andean Mountain range. There may be a few remaining Spectacled bears in Panama as well. Like its North American relative, this Andean bear is threatened by habitat loss and poaching. But their habitat is much more fragmented and many populations of Spectacled bear are isolated so the species is expected to decline by more than 30% within the next 3 generations. There are no good estimates of total population but there may be as few as 10,000 Spectacled bears left in widely separated populations.

The brown bear inhabits much of the northern hemisphere worldwide. In the New World it ranges throughout the western portions of Canada and the US with healthy populations in Alaska. Some populations of the grizzly bear (Ursus artos horribilis) subspecies are listed as Threatened under the Endangered Species Act but the majority of brown bears are considered Least Concern. The coastal brown bear found in the US and Canada is closely related to the grizzly and interbreeding between the subspecies does occur.

The polar bear inhabits the circumpolar arctic of Canada and Alaska. It has recently become the focus of concern as climate change is seriously affecting its habitat. The sea ice they rely on is projected to decrease as much as 50% by 2100. Polar bears are also highly susceptible to exposure to toxic contaminants, such as those released during oil and gas exploration. With a quarter of their subpopulations declining and another quarter more with insufficient information to assess their status, this bear is back on the IUCN Vulnerable list. The US Fish and Wildlife Service has also proposed that the polar bear be listed as Threatened under the Endangered Species Act.

The copyright of the article New World’s Four Species of Bear in Wildlife Conservation is owned by Dawn M. Smith. Permission to republish New World’s Four Species of Bear in print or online must be granted by the author in writing.