Summary

Polar bears were listed under the U.S. Endangered Species Act (ESA) in 2008 because of climate change effects on critical habitat. Declines in sea ice, the bears’ primary habitat, prompted the U.S. Fish and Wildlife Service (USFWS) and U.S. Geological Survey to recommend a “threatened” listing, which the Secretary of the Interior approved. Sea ice provides breeding, hunting, and feeding grounds and travel corridors for the bears; documented sea ice melt from increased air temperatures and changes in ocean circulation patterns in the Arctic have threatened the reliability of this habitat for polar bears. This listing indicated a new willingness for agencies to consider both observed and projected negative effects on species and their habitats.

Background

Polar bears have been the subjects of a variety of national, multilateral, and transboundary conservation agreements and treaties since the 1970s. These mammals reside in the Arctic and spend much of their lives on sea ice. In 2006, the International Union for Conservation of Nature (IUCN) determined that increasing temperatures due to global warming were significantly decreasing the amount of sea ice habitat available to polar bears. The U.S. Department of the Interior listed polar bears as “threatened” under the Endangered Species Act in 2008. Following this designation, the USFWS released a Polar Bear Conservation Management Plan in 2016. 

Implementation

Based on multiple peer-reviewed scientific reports, the USFWS and U.S. Geological Survey petitioned the U.S. Department of the Interior to designate polar bears as “threatened” under the ESA in 2006. This petition was based on both observations and projections that showed massive declines in sea ice, the bears’ primary habitat, as a result of increasing temperatures. Sea ice is critical to the survival of polar bear populations throughout the Arctic; bears use this habitat as hunting, breeding, denning, and migratory grounds. Declines in sea ice decrease the availability of this habitat for polar bears and threaten their continued survival. The Secretary of the Interior approved the petition and polar bears were officially designated under the ESA in 2008. ESA designations require restrictions on federal activities that may harm species, protection of critical habitats, federal funding support, and implementation of species recovery plans.

The listing was repeatedly challenged in the U.S. court system due to uncertainties associated with climate projections as well as the designation of critical habitat that the species does not currently use but could use in the future. In a February 2016 ruling the U.S. Court of Appeals for the Ninth Circuit ruled that the Act “requires use of the best available technology, not perfection” in science-based decision-making. The court also determined that because the purpose of the ESA is to ensure species’ recovery­––both existing and future populations––preventative measures may be required: “it makes little sense to limit its protections to the habitat that the existing, threatened population currently uses.”

The USFWS created a Polar Bear Conservation Management Plan in 2016 that identifies climate change as the primary threat to the species as reductions in sea ice threaten nearly all aspects of polar bear survival. High-priority actions identified in the plan include reducing greenhouse gas emissions, supporting international conservation efforts, and collaboratively managing subsistence harvesting between indigenous hunters in Canada (Inuvialuit) and Alaska (Inupiat) to limit potential overharvesting. Aggressive greenhouse gas emissions’ reductions are identified as key to keeping the mean global temperature increase below 2°C, and the plan identifies governments, industries, and citizens as the entities primarily responsible for this undertaking.

In addition to their designation as an endangered species, polar bears have been the subject of a number of national, international, and multilateral treaties and agreements, including:

• listings as a “species of concern” in Canada and Russia;
• Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) since 1973;
• Agreement on the Conservation of Polar Bears (1973)—a multilateral agreement signed by Canada, Denmark, Norway, the United States, and Russia, which regulates hunting and encourages the free exchange of research;
• bilateral treaty between U.S. and Russia in 2000 to protect Bering/Chukchi Sea population of polar bears; and
• a memorandum of understanding between the U.S. Secretary of the Interior and Canadian Minister of the Environment to cooperate on polar bear management and research.

Outcomes and Conclusions

Polar bears were one of the first species, along with elkhorn and staghorn corals, designated under the U.S. Endangered Species Act due to climate change concerns. Melting sea ice has already reduced and will continue to condense the amount of this critical habitat available to polar bears. This designation provides additional attention, research, and resources directed towards protecting U.S. populations of polar bears, and the Conservation Management Plan highlights the role of reduced greenhouse gas emissions in wildlife conservation. However, legal and political challenges may prevent the usage of ESA designations to justify mitigation efforts.

Since its listing, the polar bear has been joined by several other species in climate-related ESA designations, including the bearded seal and ringed seal (sea ice loss, 2012), ‘i‘iwi (temperature increase, 2017), meltwater lednian stonefly (glacier loss, 2019), and western glacier stonefly (glacier loss, 2019).

Citation

Gregg, R. M. (2021). Polar Bear Designation Under the U.S. Endangered Species Act [Case study on a project of the U.S. Department of the Interior]. Version 2.0. Product of EcoAdapt’s State of Adaptation Program. (Last updated August 2021)