by Sarah Stone and Lorenzo Cianelli, Oregon State University

Eastern Being Sea changes

Climate warming is driving major shifts in Alaska’s marine ecosystems, including changing the abundance and location of important fish and crab species. These changes are creating new challenges for the people and economies that rely on fisheries. But how do those challenges vary across the many coastal communities in Alaska, and can we anticipate change in ways that might help communities prepare and adapt?

There are few places that illustrate the impact of environmental changes on fisheries as clearly as Alaska’s Eastern Bering Sea (EBS). The EBS is one of the most productive marine ecosystems in the world, pro-viding on average more than 40% of the United States’ annual seafood catch and supporting some of the largest commercial fisheries globally. However, recent years have brought rapid and dramatic changes to the environmental conditions in the EBS, including rising ocean temperatures and declining sea ice extent. These environmental changes have disrupted the typical life cycle of many species, leading to failures in young fish surviving to adulthood, and triggering mass die-offs in several key fish populations.

Many communities along the western coast of the EBS rely heavily on both commercial and subsistence fishing, as well as on the local fish processing industry. The economic benefits (e.g., profit, employment) and social benefits (e.g., community cohesion, cultural identity, local and Traditional Knowledge) derived from Alaska’s fisheries are closely intertwined with the resilience and overall wellbeing of these communities.

As fish and crab move to new areas or fluctuate in abundance, communities must adjust their fishing practices that may have been in place for generations. Adaptation is rarely simple and can be made more difficult due to many types of pre-existing constraints: practical (e.g., size of vessels and gear types); social
(e.g., local ecological knowledge and cultural support); and regulatory (e.g., area closures and high cost of permits). While adaptation has always been part of life for coastal communities along the EBS, the current pace and scale of environmental change add new layers of complexity and urgency. Planning ahead has now become more difficult and more important for communities than ever.

Our work integrates climate, ecological, and socio- economic data to understand how changes in fish populations may affect fishing communities across western Alaska. By identifying which communities face the greatest risk, we can support strategies that build local resilience. Here, we share insights from our initial research focused on Pacific cod, and we outline how our work inspired a larger effort to explore how climate warming is reshaping opportunities and risks for fishing communities across Alaska.

Risk assessment framework

To evaluate how climate-driven changes in Pacific cod distributions could translate to risk for coastal com-munities, we adapted a risk assessment framework developed by the Intergovernmental Panel on Climate Change. In this framework, risk is quantified as the sum of three dimensions: hazard, exposure, and sensitivity.

Hazard

Hazard indicates the extent of predicted change in suitable habitat for Pacific cod. We used species distri-bution models, four decades of NOAA groundfish survey data, and regional ocean models to predict where Pacific cod are likely to be under different climate scenarios through the end of the century. To put these predictions into context, we estimated historical distributions of Pacific cod using past envi- ronmental data. We did this separately for years with “normal” environmental conditions and years with abnormally warm conditions. Using these different groupings allowed us to evaluate whether projected conditions represent a departure from historical norms, or a continuation of recent extremes.

We then linked changes in the marine habitat to terrestrial Alaska census areas using the spatial overlap between the Alaska Department of Fish and Game’s commercial groundfish statistical areas and census area boundaries (see map below). Hazard was quantified as the percent change between the estimated historical distribution and the predicted distribution within each marine statistical area. Census areas where suitable habitat was projected to decline the most were as-signed higher hazard scores, while those with stable or increasing levels of suitable habitat received lower hazard scores.

Exposure and sensitivity

Exposure reflects the degree to which communities are engaged with the EBS Pacific cod fishery. We used data from the National Marine Fisheries Service on the number of fishing permits, vessel ownership, and the total commercial landings by residents of each census area. We also included the number of processing plants within each census area as an additional measure of local fishing infrastructure.

Sensitivity includes dependency (both economic and nutritional) on Pacific cod, and adaptive capacity, or the ability of the community to cope with or adapt to changes in resource accessibility. Sensitivity indi-cators came from publicly available US Census data and included job diversity, unemployment, per capita income, fuel costs, transportation access, and extent of subsistence use.

For both exposure and sensitivity, we calculated a final value for each census area by summing the rele-vant indicators and scoring them from 1 (low) to 4 (high).

Overall risk

Each census area’s total relative risk score was the sum of its scores for hazard, exposure, and sensitivity. Scores were divided into three equal groups that could be classified as relatively low, moderate, or high.

What we learned

Several key findings emerged from our results. The first was that as the climate warms, suitable Pacific cod habitat is projected to shift steadily northward under multiple climate scenarios (see maps below). By mid-to-late century (2050–2099), these shifts are expected to become substantial and persistent. This movement northward means that suitable summer cod habitat will be located further from communities along the south-ern EBS, which is where dependence on Pacific cod has historically been the highest. In these places, changes in fish accessibility translate quickly into heightened risk. Southern regions consistently ranked highest across hazard, exposure, and sensitivity; this reflects a strong convergence of ecological change and reliance on cod. The Aleutians East region stood out as a place where declining cod accessibility most strongly intersected with a high reliance on the fishery, thus resulting in higher risk.

Another key finding involved the importance of the capacity for communities to respond to changes in overall risk. The sensitivity indicators we used (job diversity, unemployment, fuel costs, access to trans- portation, etc.) reflect a community’s broader adaptive capacity, or the resources and flexibility that help people adjust when conditions change. When we incorporated this dimension more explicitly into the model, four census areas saw their overall risk level increase. This can seem surprising at first—shouldn’t considering adaptability lower risk? But in these com-munities, limited options for alternative livelihoods and high barriers to change acted like a multiplier for risk rather than a buffer. This result really highlighted the role that social and economic constraints play in determining overall risk for communities.

We do want to emphasize that the framework we describe here should be viewed as a relative measure, rather than a full representation of each community’s real-world situation. Community resilience and adap-tive capacity are dynamic and complex processes that are shaped by history, relationships, and knowledge that cannot be attained from datasets alone. There-fore, understanding the full picture of community risk demands a more in-depth and boots-on-the ground evaluation.

Building on what we’ve learned

This initial work provided a basis for understanding how ecological shifts in fisheries translate into socio-economic risk, while simultaneously revealing opportu-nities for method refinement and expansion. Building on the Pacific cod study, we are extending this frame-work to include additional species of groundfish, crab, and salmonids, and we’re deepening and refining our analyses. Several major components define the next phase of this work:

1. Predict catch at fine spatial scales
   Species distribution models are useful tools for predicting habitat suitability, but they don’t neces-sarily perform well for capturing actualized abun-dance changes. Similarly, fish distribution does not always directly translate into catch distribution, since catchability depends on vessel characteristics, regulations, and market incentives. To address this, we will model spatial changes in catch and catch-ability as functions of environmental and regulatory conditions, population-level biomass, and species distribution model projections. This will help bridge the gap between predicted fish distributions and realized harvest patterns that shape community outcomes.
2. Link predicted catch with port-level landings data
   Linking modeled catch projections to port-level landings will allow us to evaluate how spatial shifts in fisheries might translate into where the fish are landed, and by extension, which communities may be affected. This step would allow us to estimate how changes in fisheries could alter revenue streams, processing demand, and local employment tied to specific ports.
3. Identify specific adaptation strategies at a community level
   Using community-level data, we will simulate differ-ent adaptation responses, such as diversifying target species or shifting fishing grounds, to determine which strategies most effectively reduce risk. There are a multitude of factors that go into choosing if, when, and how to respond to changes in fisheries. Because adaptation is shaped by local knowledge, institutions, and lived experiences, this phase includes participatory, semi-structured interviews with community members. Such collaboration between researchers and communities will help ground future risk assessments in local realities and support the development of solutions that are relevant, actionable, and aligned with community priorities.
4. Evaluate emerging opportunities
   While our initial work focused on risk of adverse impacts, it’s also beneficial to acknowledge that climate-driven changes in fisheries may also create new economic opportunities. Some regions are pro-jected to see positive changes in the abundance of certain species, which could provide an opportunity to engage in new fisheries, revenue streams, and enhance community resilience, especially where these increases in abundance coincide with high adaptive capacity. Expanding our framework to include both risks and opportunities will provide a more balanced understanding of how climate- driven shifts in Alaska’s fisheries may reshape resource access for coastal communities.
   

As we move into the next phase of this work, we are excited to tackle the challenges involved in linking ecological change with social and economic impacts on coastal communities—the story is far from over, and we’re just getting started. Stay tuned for what we uncover in the years ahead!

–

The authors would like to thank Sarah Wise and Kirstin Holsman at the Alaska Fisheries Science Center for their contributions to this project and the development of subsequent work.

For more information on the recently completed Pacific cod project, please see the published research paper: Stone S, Wise S, Harte M, Holsman K, & Ciannelli L. (2025). Socioeconomic risk of coastal Alaskan fishing communities to climate-driven changes in Pacific cod distributions. ICES Journal of Marine Science, 82(7), fsaf127.

https://doi.org/10.1093/icesjms/fsaf127.