This blog was written by Michele Conrad, advisor to Ocean Conservancy on achieving priority fish conservation and ecosystem goals on the West Coast. As a former state ocean policy manager, Michele represented the State of Washington on the Pacific Fishery Management Council for 15 years before starting her own consultancy. She is passionate about helping fisheries manage their way through climate change and furthering ocean conservation efforts. Protecting the ocean and its fish and wildlife for more than 50 years, Ocean Conservancy is committed to sustainable fisheries and sustainable fishing,

National Seafood Month is a great time to think about how different kinds of fish are being affected by climate change and what that could mean for the future of fisheries and the communities that depend on them. Many fish populations have been negatively impacted by a changing climate and major episodic events like marine heatwaves, such as the disappearance of the Bering Sea snow crab in 2021. But what about the fish stocks that have increased in abundance as a result of changing ocean conditions? One fish that seems to be in this category is sablefish, which is commonly called black cod (although it is not in the cod family).

Black cod can live to be more than 90 years old. They live in the depths of the Pacific Ocean from 300 to 2,700 meters (or 980 to 8,860 feet), and females, which are larger than males, can grow more than three feet long. As tasty, white, moist and flaky fish, black cod are found on menus around the world and are especially popular in Japan. 

Using different gear types for catching black cod—including pots, bottom longline and trawl throughout Alaska and along the Pacific Coast to southern California—this fishery has  remained a mainstay of sustainably managed commercial fisheries for multiple generations. Since many other fisheries in the region are seasonal—such as salmon, Dungeness crab and albacore tuna—coastal fishing communities along the west coast, including Tribal and Indigenous communities, rely on black cod to keep their fishing, fish buying and processing crews employed year-round.

The black cod population that spans the coasts of the United States and Canada is currently healthy, but as the climate and ocean conditions change, their long-term future is uncertain. Even if climate change could have some positive impacts on the stock, that doesn’t necessarily mean smooth sailing for the fishery. Fisheries are complex systems that connect ecosystems and communities and markets, which means sometimes there are surprising effects from changes, even from an increase in fish.

In 2009, scientists discovered a link between black cod recruitment (which refers to the new young fish that enter the population each year) and sea level. A climate-driven process known as “upwelling” occurs when winds blow surface waters away from an area, and deep ocean waters rich in nutrients rise (or well up) to the surface. The deeper waters are usually colder and generally produce better habitat and feeding conditions for young black cod. Over many decades, the Pacific Coast black cod population has been sustained by periodic, high-recruitment events which tend to coincide with periods of strong upwelling that provide nutrient-dense waters to feed the young fish. 

Black cod reach maturity at five to seven years, and the fish caught in commercial fisheries are typically 20 to 40 years old. In other words, the number of black cod available to catch in a given year is reflective, in part, of the environmental conditions that were present 15 to 35 years ago and since that time. So, the key to sustaining the fishery is ensuring the young black cod survive until their older years, spawning multiple times to produce fish for future generations when ocean conditions may be less productive and ultimately becoming a size that is profitable for fishers.

Black cod are targeted in many commercial fisheries. When their population is highly abundant, black cod are also difficult to avoid in fisheries targeting other stocks, such as Pacific whiting, Pacific cod or pollock in the North Pacific. This is the case now, as thousands of smaller, unmarketable black cod are being caught as bycatch in fisheries targeting other fish. For the past few years, commercial fishers have been catching increasing amounts of smaller black cod as fish from prior years of high recruitment are contributing to the spawning stock. According to the most recent stock assessment produced by the Northwest Fisheries Science Center of the National Marine Fisheries Service (NMFS), the recruitment events from 2020 and 2021 are the highest on record. Some of these smaller black cod are being caught as unavoidable bycatch, which is a challenge for fishery managers. 

As if on cue, earlier this year, the Government Accountability Office (GAO) released a report, Federal Fisheries Management: Efforts to Reduce and Monitor Unintentional Catch and Harm Need Better Tracking, which calls for the NMFS and Regional Fishery Management Councils to gather more data from fisheries and produce more reliable bycatch estimates to better inform fisheries-management decisions. In response to the GAO’s recommendations, NMFS is planning to produce an annual online report on bycatch trends and estimation methods that will be available by the end of March 2025.

While accounting for total catch, including bycatch, is critical to ensuring fisheries are managed sustainably for the long term, no one—especially fishers—wants to catch fish they cannot sell. As the market has been saturated with black cod for the last two years, prices have dropped to record low levels, which does not bode well for the coastal fishing communities that depend on the revenue generated from black cod to sustain them throughout the year. 

For the past few years, black cod quotas in the North Pacific and off the U.S. West Coast have steadily increased. In December 2023, Alaska fishermen urged managers in the North Pacific to adopt lower quotas for 2024 in response to the weak market as the fishery attained only 60% of its Total Allowable Catch (TAC) in 2023, but to no avail. Similarly, this June, the Pacific Fishery Management Council (PFMC), responsible for managing fisheries along the U.S. West Coast, adopted annual catch limits for black cod (sablefish) for West Coast fisheries for 2025 and 2026 that are more than double the limits for 2023 and 2024. This decision was made despite concerns expressed by fishery participants for how higher catch limits could exacerbate low market conditions and even though only 72% of the lower black cod limit had been attained in 2023.

NMFS’ planned online bycatch report will not come too soon as high sablefish recruitment events were detected by NMFS surveys again in 2022, and the stock assessment indicates the population will stay at these high levels for at least the next ten years. This projection, however, will hold true only if environmental conditions for black cod remain favorable, sufficient prey are available to support their increasing numbers, and total catch, including bycatch, is properly managed to ensure sustainability of the population. 

Climate change definitely adds to the challenges of managing fisheries, but even fish stocks that experience an increase in abundance as a result of changing environmental conditions need to be well-managed. Take action with Ocean Conservancy and join the movement to protect our ocean, its fisheries and its wildlife from the impacts of climate change.