Sea ice loss means changes for Arctic species and communities

Conditions for species are changing due to sea ice decline

As sea ice declines in the Arctic, conditions are changing for many species in the region that are of critical ecological, economic and/or cultural importance to local communities and to people elsewhere. These changes can threaten Arctic human societies – notably, coastal Indigenous Peoples whose cultures and food security are centered on sea ice and its biodiversity.

For example, in Igloolik, an Inuit community in Nunavut, Canada, changing sea ice is one of many factors contributing to a high prevalence of episodes of food insecurity among residents. Igloolik is located on a small island and its residents require either open water for boating or stable ice for travel by snow machine in order to hunt walrus, fish, access caribou hunting grounds, and travel to other communities. The ice season in the sea near Igloolik declined from nine to seven months between 1979 and 2008, with freeze-up moving from November to December. This means a longer period during which hunting is not possible. Changes in ice dynamics also mean there have been fewer walruses near Igloolik in recent years, so they are either not accessible to hunters or harvesting the walruses costs more in fuel. These ice-related changes have led, at times, to acute shortages of country foods.

It is important to note that sea ice decline is not, by itself, responsible for population decline in any individual species. However, it plays a key role in combination with other factors The Arctic is vast, and changes across the region due to declining sea ice will not be uniform. Individual species’ responses to these changes will be uncertain and varied.

What we know

- Changes in the Arctic are happening too quickly for some species to cope. Particularly vulnerable are species with limited distributions, specialized feeding or breeding requirements, and/or high reliance on sea ice for part of their life cycles. Amongst others, the report identifies the hooded seal, narwhal and polar bear— species that are vitally important to Indigenous communities— to be vulnerable to change.

- Some sub-Arctic species are expanding northwards into the Arctic, while some Arctic-adapted species are losing habitat along the southern edges of their ranges. For example, commercially fished snow crab has expanded northward in the Bering and Chukchi seas and moved into the Barents Sea. Other northward-extending species include several crab and mollusk species in the Chukchi Sea and the blue mussel in Svalbard. Great black-backed gulls and razorbills have expanded to Hudson Bay, horned puffins to the Beaufort Sea, and great skuas to Svalbard. Conversely, the range of the ivory gull in Canada has contracted over the past 30 years with population declines of over 70% from the early 1980s to 2009, but exact causes of decline are unknown. Ice melt drives Pacific walruses in the Bering and Chukchi seas onto land if the receding ice edge moves too par north for them to feed.

- Development activities, ocean acidification and contaminants are also threats to ocean life, and these will interact with changes in sea ice.

What is to be done?

The “Life Linked to Ice” report contains four recommendations to the Arctic Council:

(1) Facilitate a move to more flexible, adaptable wildlife and habitat-management and marine spatial planning approaches that respond effectively to rapid changes in Arctic biodiversity.

(2) Identify measures for detecting early warning of biodiversity change and triggering conservation actions.

(3) Make more effective use of local and traditional knowledge in Arctic Council assessments and, more broadly, in ecological management.

(4) Target resource managers when communicating research, monitoring and assessment findings.

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