Unsupported Browser Detected

Internet Explorer lacks support for the features of this website. For the best experience, please use a modern browser such as Chrome, Firefox, or Edge.

West Coast Research Alliance Projects Climate Effects, Management Options for Key Species

March 16, 2023

‘Future Seas’ uses models to depict changing outlook and strategies.

The range of sardines, swordfish, and albacore tuna off the West Coast will shift north in coming decades as climate warming moves their habitat in that direction. A new analysis focused on these three benchmark species as ecological barometers.

Future Seas is a collaboration of diverse ecologists, economists, oceanographers, and other scientists from NOAA Fisheries, the University of California Santa Cruz, and other institutions. It projects impacts of climate change on the fisheries off California, Oregon, and Washington. They are compiling the most recent science through models of the California Current Ecosystem to help coastal communities anticipate and adjust to climate-driven changes and develop strategies to manage impacts.

The effort is a pilot project for NOAA’s new Climate, Ecosystems, and Fisheries Initiative. Future Seas links high-resolution ocean models of the California Current System with ecological and social models to assess options for climate-ready management strategies.

The models that simulate future conditions show that an increase in sea surface temperatures of 2 to 4 degrees will change the ecosystem in unprecedented ways. While the predictions of different combinations of models called ensembles vary, one of the main drivers of change will be the redistribution of species in coastal waters. That will influence fishery dynamics including openings and closures, catch allocations, and the ports where fishing fleets are based.

The models have only recently begun to show how climate change is likely to affect the biomass, or overall volume, of different species. The scientists concluded: “It seems likely that engagement of U.S. West Coast communities with specific species and fisheries will change in the coming decades, and flexibility in both fishing grounds and catch portfolios will be important processes for community resilience.”

Figure 1.
Fig 1: Schematic of the first phase of the Future Seas project. High resolution ocean models are used to generate retrospective ocean hindcasts and re-analyses, and to dynamically downscale global climate projections to provide the foundation for a range of modeling approaches aimed at quantifying and projecting aspects of three species and their U.S. West Coast fisheries: Pacific sardine (the purse seine fishery), swordfish (the drift gillnet fishery), and North Pacific albacore (the surface hook-and-line fishery). Silhouettes of species indicate relevant models and outputs.

Delivering on Climate Strategy

These analyses will help deliver on the NOAA Fisheries Climate Science Strategy. It aims to provide long-term projections of how climate change will affect fisheries, which fisheries and communities may be most vulnerable, and which are most resilient.

Their analysis centers on three representative species, each with ecological and economic values likely to be affected by climate change. Sardines are small boom-and-bust pelagic species known for supporting Cannery Row in Monterey around the time of the Depression in the 1930s and fluctuating since. Swordfish are large, highly valued fish that feed deep underwater. Albacore tuna migrate long distances between spawning areas and feeding grounds where they mature and have expanded with warming temperatures.

All three will likely shift north toward the pole, with impacts on fishing fleets and implications for local ecosystems. For instance, albacore landings are likely to shift north, benefiting fishermen in the Pacific Northwest. By contrast, Southern California fishing communities that have increasingly turned to albacore to make up for other fisheries that have declined may lose out. The shift may be felt especially by smaller fishing vessels that rely on albacore to supplement their fluctuating catch of other species, but have less flexibility to travel long distances to fish.

“Larger vessels are projected to be more responsive to changes in albacore distribution, employing a ‘follow the fish’ adaptation strategy, and switching landing ports more quickly if it becomes economically beneficial,” the analysis concludes. “Small vessels, which have more limited mobility, are more likely to keep landing in the same community.”

The analysis examined the likely geographic change in the distribution of each species, in light of their management. Here is how they break down.

Figure 2.
Fig 2: Maps of locations in the CCS with novel or analog projected climates. Maps are shown for August at the end of five decades, under ROMS-IPSL. Colors represent an analog climate (green), or three scales of climate novelty (yellow, orange, red). The maps show each grid cell’s majority classification over a 5-year period ending in the specified year (e.g. 2016–2020). Novelty was calculated using the hypervolume method, based on a climate envelope of SST, dissolved oxygen, mixed layer depth, and eddy kinetic energy (Smith et al., 2022). The black line is the exclusive economic zone (EEZ).

Management Plan
Highly Migratory Species

Fishing Gear
Deep-set buoy gear, longline, drift gillnet

Current (2023) Stock Status
Not overfished and no overfishing

Gear restrictions, time and area closures, permits

Geographic shift
About 200 kilometers north

Change in landings
Not determined



Management Plan
Coastal Pelagic

Fishing Gear
Purse Seine

Current (2023) Stock Status
Overfished; directed fishery is closed

Geographic shift
500-800 kilometers north

Change in landings
20-50 percent decline in Southern California; up to 50 percent increase in Pacific Northwest



Management Plan
Highly Migratory Species

Fishing Gear
Troll, pole and line

Stock Status
Not overfished or subject to overfishing


Geographic shift
400-500 kilometers north

Change in landings
5-60 percent decrease in Long Beach and San Diego by 2100; 25-100 percent increase in landings in Pacific Northwest relative to last two decades



Future Seas

Western Regional Action Plan

NOAA Fisheries Climate Science Strategy

Last updated by Southwest Fisheries Science Center on April 26, 2023