Protecting Blue Corridors: The Bering Strait

This story originally appeared in the 2022 Protecting Blue Corridors report, pages 33-35. For more information and references, please see the report.

The Bering Strait connects the Arctic to the Pacific Ocean. Each year it hosts immense seasonal migrations of more than one million marine predators, including bowhead, beluga and gray whales, seals and walrus. The Bering Strait is a key migratory corridor, a persistent hotspot for many marine species, and is one of the world’s most productive marine ecosystems.

Seasonal migrations of Arctic and subarctic marine mammals closely follow the timing of sea ice retreat north in spring and its advance south in autumn. The highly productive, plankton-filled cold Arctic waters north of the Bering Strait also attract temperate cetacean species from the Pacific Ocean up through the Strait and into the Arctic Ocean to exploit these rich feeding grounds in summer months. Gray whales travel more than 16,000km annually to and from Mexico. Humpback whales frequent the Bering Sea in summer and can be found as far north as the Chukchi and Beaufort Seas. As well as their importance to the marine ecosystem, populations of whales that migrate through the Bering Strait are of immeasurable importance to coastal Indigenous Peoples in Alaska and Russia, who have relied on them for millennia for their culture, nutrition and livelihoods.

Conservation challenges

A changing Arctic

The Arctic is warming more than twice as fast as the rest of the planet due to anthropogenic climate change and is now warmer than it has been at any time during the last 2,000 years. A major consequence of this is loss of sea ice. Summer ice extent has declined by 40 per cent since satellite observation began in 1979 and what remains is younger and thinner, melts earlier in spring and re-freezes later in autumn.

Sea ice is an important habitat for Arctic marine mammals and, until recently, it has been a physical barrier to heavy industrialization of the Arctic Ocean and associated impacts. However, as the ice-free season lengthens, this is rapidly changing. Financial experts estimate that future development in the Arctic will attract approximately a trillion dollars of new spending in the next 20 years. Realisation of new development and infrastructure plans, stimulated by global demand for resources, is now possible due to the climate crisis.

Extremely warm conditions in recent years have put the Pacific Arctic marine ecosystem under high pressure. Whales in the Bering Strait region are contending with changes in prey availability, a higher risk of predation by killer whales and changes in sea ice and other climate drivers that cue migration and other life events. Early signs of transformative change in the region include shifts in the productivity and distribution of fish species, changes in migrations of bowhead and beluga whales, and unusual mortality events for ringed, spotted and bearded seals and gray whales.

Growing risks for cetaceans

On top of these dramatic ecosystem changes, multiple anthropogenic stressors are growing in the Bering Strait region. Projected increases in ship traffic and expanding commercial fisheries carry direct risks for cetaceans. Known as the “fish basket” of the United States, the southeastern Bering Sea contains major fish stocks that make up a US$2 billion fishery and account for about half the seafood landings in the country. As these fish stocks move northwards due to climate change, so too will commercial fishing pressure. In 2020, the Russian Federation announced plans to open the first commercial pollock fishery in the Chukchi Sea to take advantage of this species’ apparent range expansion.

Shipping activity in the Bering Strait overlaps in space and time with whale migrations and brings several risks, including oil spills, ship strikes and underwater noise pollution. The number of ships transiting the Bering Strait has almost doubled in the last decade.

Where only 262 transits were recorded in 2009, in 2019 approximately 494 ship transits were observed through the Strait, with large increases projected in the future. Excess underwater noise pollution from current shipping – the amount of additional noise on top of the ambient underwater soundscape – is well above levels known to have a negative impact on whale communication.

In addition to increases in shipping through the Bering Strait for local or national commerce, with the loss of sea ice, new global shipping routes through the Arctic are materializing to connect the world’s oceans. Of four such routes, three would pass through the Bering Strait: the Northwest Passage, the Northeast Passage (which includes the Northern Sea Route) and the Transpolar Sea Route. All offer significant benefits of shorter distances compared to those through the Suez and Panama Canals.

Conservation opportunities and solutions

International action to regulate shipping needed now

The Bering Strait is clearly an important migratory corridor for marine wildlife and is vital for the many coastal Indigenous Peoples who use marine resources as an integral way of life. Climate change is also creating opportunities for commercial and industrial growth that will result in new and elevated risks for the Bering Strait marine ecosystem and its components, including endemic species like bowhead and beluga whales and seasonal visitors such as gray and humpback whales.

Commercial activities including fishing and shipping must be managed through national action and international cooperation, especially between the Russian Federation and the United States, whose national waters abut in the Bering Strait. Development of a holistic system to manage shipping, thereby improving maritime safety and environmental protection, could include the use of emerging e-navigation technologies to enable real-time monitoring and information exchange; development of seasonal or dynamic MPAs; adoption of voluntary or mandatory speed restrictions and standards of care and operation led and implemented by the maritime industry.

WWF is working with governments, local communities, and other conservation organizations in Russia and the United States to identify area-based protections in Bering Strait to protect whales and other marine mammals, and the communities that rely on these areas. Areas to Be Avoided (ATBAs) are special areas identified by the International Maritime Organization (IMO) to keep large vessels away from sensitive habitats. WWF has identified the Diomede Islands as important areas that require further protection and recommend implementing ATBAs around both islands.

With transformation of this marine ecosystem underway, protection of these migratory corridors to maintain ecological connectivity and the immense natural values of the region is a matter of urgency.

Learn more about WWF’s new report, Protecting Blue Corridors.