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The sea’s limit

Kaginovskiy

International Gulf of Alaska Expedition graphic

 

The unprecedented voyage of the R/V Professor Kaganovskiy to probe the resources of the Gulf of Alaska this winter has made one thing clear:

As with the land, so with the sea. There is good pasture. There is middling pasture. And there is bad pasture.

This reality is visually evident in the graphics of zooplankton biomass pulled together by scientists (see above) involved with the International Gulf of Alaska Expedition organized by Canadian Richard Beamish – the grand, old man of Pacific salmon research. 

Beamish, now 78, has spent decades pondering the moving target of carrying capacity for salmon in the Pacific Ocean.

More than 20 years ago, he began warning that scientists know way too little about the environment most important to these fish.

Salmon, he noted in a paper published in the ICES Marine Journal in 1997, “spend most of their life in salt water, during which there is extremely high mortality, it is clear that the ocean habitat must have a powerful influence on abundance. Fishing clearly complicates this basic relationship, but we must not ignore that the underlying relationship still exists.

“Clearly, targets for rebuilding and increasing catch must be based on the productivity of the ecosystem and not on past conditions or perceived historic high abundance levels. Ignoring natural fluctuations in the ocean ecosystem may result in costly and wasteful investments; more importantly, the intervention into a poorly understood process may create problems that are not easily corrected.”

At the time – with Alaska salmon harvests for the first time reaching 200 million – there were concerns a “regime change” in North Pacific sea conditions could bring cooler waters likely to spark a major drop in salmon survival at sea.

And, in fact, salmon catches that had been climbing steadily since the 1980s did slump somewhat in the late 1990s and early 2000s only to come roaring back.

By 2009, Beamish was writing that although there “are different interpretations of the impacts of climate on Pacific salmon…there is also agreement on many issues. One important agreement is that the current abundances of Pacific salmon are at historic high levels of abundance. This indicates that, in general, the recent climate is favorable for Pacific salmon production.

“However, not all species and not all stocks are prospering. The reasons for the high abundance of Pacific salmon and the low abundance of some species and stocks are not well understood.”

The differences in abundance are a big issue in Alaska where low-value pinks now dominate commercial harvests, and where some research has emerged indicating the bounty of pinks could be reducing populations of prized sockeye (red), coho (silver) and Chinook (king) salmon.

“All (Copper River) sockeye salmon stocks examined exhibited a downward trend in productivity with increasing Prince William Sound hatchery pink salmon returns,” scientists studying the Exxon Valdez oil spill discovered in 2017. “While there was considerable variation in sockeye salmon productivity across the low- and mid-range of hatchery returns (0–30 million), productivity was particularly impacted at higher levels of hatchery returns.”

Though there was an apparent, human-caused reduction in sockeye numbers due to a combination of hatcheries and fisheries management aimed at maximizing the commercial catch of pinks in the Sound, the study noted there appeared to be no long-term reduction in salmon numbers due to the oil spill, a human-caused disaster.

Hatcheries are widely viewed as a good thing in Alaska, even though the consequences of such nature tampering are unstudied and unknown. The state’s chief fisheries researcher dismissed questions about hatchery salmon affects on the environment at a meeting of the state Board of Fisheries by explaining the issue is too complicated to study.

The longest journey

The Kaganovskiy scientists from Canada, Japan, Korea, Russia and the U.S. did, however, took some baby steps toward trying to untangle the puzzle with their work in March and February.

What they found at sea raised more questions than it provided answers although it did serve to underline what a lot of scientists have argued for a long time – that the productivity of the ocean has limits that shift with the seasons, the climate and by area.

Or, in simple terms, the ocean that Alaska’s commercial salmon farmers ranch is just like a ranch. You can only put so many cattle on the pasture before they overgraze the land and begin to starve.

The ocean problem at this time is that no one yet has a clue as to exactly how many salmon the marine pasture can support. The scientists aboard the Kaganovskiy estimated there were but 55 million salmon on the Gulf pasture late this winter.

All of which raised big question number one. Where were the rest of them?

The Alaska Department of Fish and Game has forecast a summer harvest of more than 213 million salmon. About 26 million of those are supposed to be Bristol Bay sockeye, which could have been in the Bering Sea and outside the study area.

But even with the Bay salmon removed from the count, there are 187 million salmon to be accounted for, an estimated 138 million of them pinks.

The Kaganovskiy team estimated only 4.2 million pinks in the Gulf, a tiny fraction of summer’s expected bounty. Speculation is that the fish might have been south of the survey area, which went as far south as the latitude of Puget Sound.

The pinks the survey did find were concentrated in warmer, more southerly waters.

survey.JPG

Sockeye, meanwhile, clustered in cooler waters to the north and west of the pinks. There were an estimated 9 million of them, more in keeping with Fish and Game predictions for the year.

After a dismal 2018, the state agency is calling for a return of about that number to north Gulf waters this year. At this point, it also looks like the run could be better than forecast.

The projected Copper River catch of 1.1 million was nearing 800,000 as of Thursday, and the number of fish escaping into the river is now 180,000 over the goal and already near 90 percent of the minimum escapement at a time when managers expect to be reaching 60 percent.

Sockeye are also continuing to swarm the Kenai Peninsula’s Russian River where a mob of anglers attracted by liberalized bag limits appear to be putting only a tiny dent in the number of salmon going upstream.

The river has already topped its maximum escapement goal of 42,000, and fish continue to push through the weir at a rate of 5,000 per day. The Russian is a small, clearwater stream less than 100-feet wide at its widest.

Fish and Game has now upped the limit to nine sockeye per day to try to encourage a higher harvest.

The later-arriving and bigger Kenai River run of sockeye is this year projected to help provide for a commercial harvest of 3 million in Cook Inlet. That would be about three times the catch of last year.

Sockeye in the Gulf in February and March were found to be feeding mainly on krill, which were generally concentrated in the areas where most sockeye were caught. The small, shrimp-like creatures are common prey in oceans around the world. 

The concentration of predatory salmon in areas full of prey was not a surprise, but other things were, starting with that lack of pinks and ranging through an unexpected abundance of coho to the strange mixture of skinny chums and fat chums caught in the same area.

“A surprising difference in fish condition over the study area but even within a single set,” the scientists reported. “The largest difference was observed for chum salmon when fish of both good (robust) and poor (skinny) condition would be captured in a set. DNA analysis will help determine if the variability is due to stock origin.”

Fish that had to travel greater distances to prime feeding grounds or battle currents to get there would be expected to be skinnier than fish that rode in on the current or arrived from nearby.

Scientists are still sorting and further analyzing data they obtained at sea. More is expected to come from that. Beamish, meanwhile, is looking for funding to continue the project in 2020.

He doesn’t expect that to be easy. Basic research funding is hard to find. Almost everyone supports it in theory, but foundations, governments and individuals aren’t rushing to fund it.

Some think its a small miracle Beamish pulled this off once, but the scientists in their summary noted the expedition “can be considered an extremely successful proof of concept that validates the International Year of the Salmon Initiative.”

No Alaska scientists participated in the project, but some state fisheries biologists did contribute to designs of research for gathering data and are participating in some data analysis.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

9 replies »

  1. Your title “The Sea’s Limit” refers to the Pacific Ocean salmon carrying capacity so why avoid current Pacific salmon carrying capacity estimates? You list the 200,000 million Alaska commercial salmon harvest annually. The 55 million salmon on the Gulf of Alaska pasture late this winter. The 5-10 million pinks in the Gulf of Alaska. The one million Copper River commercial salmon harvest. The 42,000 Russian River sockeye escapement and the projected 3 million Cook Inlet commercial sockeye harvest. These numbers are somewhat meaningless to projecting a Pacific Ocean salmon carrying capacity.

    To discover a Pacific salmon carrying capacity you would need to gather a tremendous amount of data. Some of that data would include the daily calorie intake for each type of salmon and the amount of marine ecosystem necessary to produce that calorie intake. You don’t even attempt this capacity investigation.

    You also didn’t attempt to investigate what the nations surrounding the Pacific have been “hatchery dumping” into the Pacific for the past 50-100 years. You could have gathered these estimates to project if hatchery production added to wild production could be overwhelming the Pacific salmon carrying capacity. This data is openly available and projects Pacific hatchery salmon production between 5-10 billion annually.
    You could of compared your few hundred million harvested salmon to the 10 billion hatchery dumped salmon and how Pacific wild salmon somehow survive this monstrous artificial cycle.

    Your article may be about the Pacific commercial salmon harvest but it does not address the current Pacific salmon carrying capacity. Why not do an real Pacific salmon carrying capacity article?

    https://pdfs.semanticscholar.org/5be0/2e4b6030a5e2aa3a2c358a0d1883ce44bb8d.pdf

    • Why? Because no one can begin to hazard a guess. Salmon are in the middle of a food pyramid constantly shifting at the base with both top-down and bottom-up influences.

      The best scientists out there (and that’s not me) don’t really have a clue as to what the carrying capacity other than it is now significantly greater than in the 1970s when the North Pacific was cold.

      I knew very good scientists here in the ’80s who would have said you were nuts if you argued 200M per year salmon production possible for Alaska, and yet we’ve topped that three times in the last six years and the forecast is that we’ll do it again this year.

      • Those 1980 scientists were correct about Alaska not being able to harvest more than 200M wild salmon annually under “normal ocean conditions”. They did not considered or expect nations to start dumping hundreds of billions of hatchery salmon on top of Alaska’s wild salmon.

        Commercial fisheries and aquaculture then spent many millions of dollars to create abnormal ocean conditions to implement a North Pacific regime change. Those efforts basically operated from 1980 until now, over-harvesting and reducing wild king and silver salmon while expanding hatchery sockeye, pink and chum salmon. These manipulated marine resources expanded commercial fisheries while reducing sport fisheries.

        Selective hatchery enhancement is still being used today to implement this regime change. Superior commercial fish numbers are being used to reduce sport fish numbers. Those reduced sport fish numbers then began following the regime shift that eventually caused many sport resources to eventually collapse from starvation. Any sport resource escaping the regime shift was then eliminated through excessive commercial harvest and by-catch.

        Starvation almost precisely mimics (A Lack Of Abundance) therefore the “regime change plan”
        became “A Lack Of Abundance Plan”. You don’t need to know the North Pacific salmon carrying
        capacity. Only that everything has been artificially stacked against wild sport resources while artificially stacking everything for commercial resources. Total ocean resources are irrelevant, “artificial regime change and excessive commercial harvest of wild sport resources” is all that is relevant.

        Too Many Salmon in the Sea,
        https://www.google.com/amp/s/relay.nationalgeographic.com/proxy/distribution/public/amp/news/2014/03/140331-salmon-seabirds-pacific-fish-animals-science

        Regime Shift
        https://www.regimeshifts.org/item/406-north-pacific-ocean

  2. Thank you Professor Kagnaiskiviy (sp) (or something like that). That’s some good research showing the different species inhabit different areas (except for the Kings which are out-competed for food by the sum of all other species). Particularly all those damn pinks! Is there really that much money in pinks?

  3. Thank You Craig for this report. Very interesting indeed.

    I find it hard to believe that the Big Three fish processors in Seattle & Tacoma do not provide funding to this research ? I mean it is in their best interests.

    Perhaps you should give them a call.

    Thank You again,

    Frank Flavin Photographer

     

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