Are hatchery releases affecting Alaska’s wild salmon?

Hatcheries have become a hotly debated topic in the news recently, particularly regarding pink and chum salmon and their potential effect on other species, ocean carrying capacity and the like. Critics of pink and chum salmon hatchery production claim that too many pinks and chums are causing declines in salmon and seabird populations. This has led to calls to reduce or eliminate hatchery production in Alaska and elsewhere. Meanwhile, supporters point to record returns in recent years of both hatchery and wild salmon as reasons not to be concerned. This conflicting information has led to uncertainty and confusion.

The purpose of salmon hatcheries in Alaska is to supplement wild stock abundance for public benefit. There is little doubt that hatcheries have accomplished this purpose. In 2018, an estimated $450 million of hatchery origin salmon were commercially caught. Alaska’s hatchery production contributes nearly 1 billion meals annually across the globe. Chinook, coho and sockeye hatchery releases support significant sportfishing opportunities, notably in Southcentral and Southeast Alaska. These are significant benefits, both in terms of economic output and food security.

While the benefits of increased fishing opportunity and associated economics are easy to measure, the potential risks which include harm to wild stocks tend to be more difficult to assess. Changes in ocean conditions can affect a variety of aspects in salmon biology, including migration timing, distribution, growth, feeding habits and production trends. And there are countless interrelated variables that affect salmon growth and survival in the ocean. A lack of scientific observations for salmon in the North Pacific has limited our understanding of these changes and the effects they might have on Alaska’s salmon. Where we do have information, however, there is strong evidence that ocean conditions affect the survival and production of all of Alaska’s salmon species.

From the 60,000-foot level, the data demonstrates that Alaska’s salmon stocks by and large remain healthy and productive, despite an ever-fluctuating ocean environment and hatchery releases. Changes that may cause reduced productivity in some stocks in some areas appear to favor increased productivity of others. Certainly, chinook salmon stocks across the North Pacific are depressed, but the reasons behind this are unclear and indications are that this may be turning around. The fact that some salmon species — or any species, for that matter — have population fluctuations is not uncommon, and we’ve seen these trends before.

We know that conditions are rapidly changing in the ocean. The water is warming, which affects the food web, among other things. The distribution of salmon prey is shifting with less nutritious feed moving northward. At the same time, salmon metabolism and caloric demands increase as water warms. In other words, with higher energy demands and lower energy food available — you’ve got a double-whammy affecting salmon growth and survival.

It is understood that all habitats have limits to the abundance of organisms they can support. Knowing what these limits are at any point in time, however, is difficult to quantify. So are we overpopulating our marine habitats with hatchery fish? Releases of hatchery salmon are not seeing meaningful increases in Alaska or internationally. Hatchery production levels have remained stable in Alaska since the mid-1990s, and in the entire North Pacific since the mid-1980s. Pink salmon make up less than a quarter of the salmon biomass in the ocean and Alaska’s hatcheries contribute about 2%. In fact, about 85% of pink salmon in the North Pacific are wild stocks, not hatchery stocks.

Unfortunately, the data are not definitive. There is no single cause or smoking gun responsible for recent changes in any salmon populations. There are an awful lot of moving parts and a whole lot that we don’t know. More research is needed. Unfortunately, marine research is costly and in these times of austerity, Alaska has limited resources to assess the changing conditions at sea. This said, we are cooperating with other entities to collaborate on needed research.

Given the absence of definitive information, precautionary management principles urge caution. The department is not seeing any proposals for further increases in hatchery production of pinks or chums, the two species that dominate the releases, nor are any anticipated in the next five years based on discussions with Alaska’s private nonprofit hatchery operators. Any requests for increased production will be evaluated under a precautionary lens through the hatchery permitting process, which is public and transparent, in which I have final approval for release numbers.

As Alaskans, we all care about salmon. We are all concerned when a stock of salmon is not doing well; we want to know why, and we want to do something about it. Alaskans can take a lot of credit for maintaining healthy salmon stocks.

Thanks to sound policies, precautionary management principles and an active public process, we have the best salmon management in the world. I look back at where we started at statehood with depleted salmon runs across the state. I credit the architects of the Alaska Constitution, who had the foresight to include principles of sustainable management of our resources into our constitution. Sixty years later, after many evolutions in policy, management and the variable ocean conditions, Alaska’s principled and adaptive management has continued to provide healthy stocks and benefits to all Alaskans. That said, we need to remain adaptive in the face of inevitable change and uncertainty. Sustainability will continue to guide our management philosophy.

Doug Vincent-Lang is the commissioner of the Alaska Department of Fish and Game.

The views expressed here are the writer’s and are not necessarily endorsed by the Anchorage Daily News, which welcomes a broad range of viewpoints. To submit a piece for consideration, email commentary(at)adn.com. Send submissions shorter than 200 words to letters@adn.com or click here to submit via any web browser. Read our full guidelines for letters and commentaries here.