Site icon Craig Medred

Ecosystem chaos

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The golden fish of Alaska’s private, ocean-ranching hatcheries/Wikimedia Commons

With Canadian and Pacific Northwest scientists readying a claim to yet more evidence of hatchery pink salmon overgrazing the pastures of the North Pacific Ocean to the detriment of Chinook and other prized salmon species, a growing group of Alaskans is back before the state Board of Fisheries (BOF) asking for a freeze on hatchery fry releases.

 

Led by the Kenai River Sportfishing Association (KRSA), eight organizations and 11 individuals – most of them Cook Inlet commercial fishermen – Thursday filed a new emergency petition asking the board to rescind the permission given the Valdez Fisheries Development Association to pump another 20 million pink salmon eggs into its hatchery this summer.

An earlier petition died on a tie vote.

“This petition, though similar, is different in that it requests that the BOF exercise its own authority for oversight of hatchery salmon production and halt the 20 million additional egg take for PWS hatcheries,” KRSA executive director Ricky Gease wrote in a letter to the state. “I will follow up with nine attachments of scientific reports on issues with hatchery salmon production and the North Pacific Ocean, which are cited in the petition.”

Four of those studies are new this year. One is still in review, but details the discovery of significant drops in the abundance of Bering Sea plankton when masses of pink salmon show up in the Bering Sea. Many of those fish are the spawn of wild humpies, as Alaskans best know the smallest and most common of the Pacific salmon; but humpy numbers are significantly boosted by close to 1 billion Alaska hatchery pinks and another 1 billion Russian hatchery fish.

Alaska banned fish farming about three decades ago, but it jumped heavily into ocean-ranching. It’s free-range hatchery salmon,  marketed as “Alaska wild,” have become a key part of the Alaska commercial fishing industry.

But Sonia Dawn Batten from the Alister Hardy Foundation for Ocean Science in Nanimo, British Columbia, and Seattle scientific colleagues are joining those warning all these hatchery humpies could be bad news for other species of wild salmon.

Hatchery pink salmon now trump climate change as a cause of concern at the ecosystem level, the draft of a study written by Batten says.

“The influence of pink salmon on the summer plankton around the Aleutian Islands and in the southern Bering Sea was a much stronger signal than environmental variability caused by the cold/warm stanzas experienced by the Bering Sea during the same (2000 to 2014) time period,” she wrote.

“Growing evidence indicates that foraging pink salmon affect feeding and reproduction of seabirds and growth and survival of sockeye salmon, coho salmon, and chum salmon,” Batten and colleagues concluded. ” The trophic cascade caused by pink salmon has important societal implications, especially to the extent that pink salmon may have influenced the declining size-at-age and abundance of Chinook salmon throughout Alaska.”

Chinook are the big king salmon which made the Kenai River famous. Thirty-three years ago as of Thursday, the late Les Anderson pulled the 97-pound, 4-ounce world record from the Kenai. In the years that immediately followed, many speculated the Kenai would one day produce a 100-pound king.

That speculation ended long ago. The big kings started disappearing from the Kenai in the late 1990s. Since 2003, the biggest fish on record is an 80 pounder. Over the last nine years, only one state-certified Kenai trophy king has been caught. It weighed 71.1 pounds.

In 1985, 366 million hatchery pink salmon fry were dumped in Alaska waters, according to the Alaska Department of Fish and Game (ADF&G). By 1996, the number was up to 999 million, almost three times as many. Releases peaked at over 1 billion in 2014.

Trophic cascades

A trophic cascade occurs when predator numbers are so radically shifted they spark a chain reaction that ripples through an ecosystem from top to bottom. Aldo Leopold, a pioneering figure in wildlife ecology, offered the first description of the phenomenon long before the term itself appeared. Leopold observed that when wolves were exterminated in the American Southwest, deer populations exploded. A booming deer population grazed vegetation down to almost nothing which altered the structure of entire plant communities.

Following on the work of Leopold,  Nelson Hairston, Frederick E. Smith and Lawrence B. Slobodkin generally get credit for formalizing the trophic cascade theory, although they didn’t use the term either.

What they did do is document that the phenomenon Leopold observed ran two ways: If predators became too abundant, they could decimate prey. The result was a drastic reduction in the plants eaten by prey, and again the entire structure of plant communities were altered or preserved.

The scientists’ “green world” hypothesis essentially argued that predators were vital to keeping prey in check so the herbivores didn’t devour every edible plant and turn the planet into a desert.

As with most natural phenomenon, trophic cascades produce winners and losers. And nowhere do things get more confusing than in the ocean where many species of fish compete for the same prey.

In the Bering Sea, lots of young salmon feed heavily on copepods, a small, shrimp-like crustacean.  And the fastest growing of Alaska salmon, humpies appear to have a competitive advantage over slower growing species.

Scientists can tell when copepods are being dramatically cropped off because diatoms – a microscopic, single-cell algae on which copepods feed – explode. That increase is not necessarily a bad thing. Phytoplankton that use carbon dioxide to generate energy, diatoms give off oxygen as waste. They are credited with annually providing about 25 percent of earth’s oxygen.

One could argue that by consuming vast quantities of copepods, hatchery pinks are playing a small role in combating CO2 driven climate change. Ocean ecosystems are complicated and full of trade offs. It has long been theorized that pink salmon naturally developed distinct an even-year, odd-year cycle to their returns built around their own over-utilization of the ocean.

Odd-year runs are so big that copepods populations take a beating from which it takes more than a year to recover. As a result, even-year humpies find less food and fewer are able to survive.

From 2000 to 2008, the average even-year production of pinks was only about 60 percent of the odd-year production, according to salmon processors in the state. The processors suggested hatcheries might be able to more than double the even-year production and bring the odd-year production up to 70 million from an average of about 56 million.

Large numbers of Alaska humpies benefit processors set up to can salmon and a small number of commercial salmon seiners who fish Alaska. Most Alaskans – commercial, subsistence, personal-use and sport fishermen – get the most benefit out of Chinook, those big kings of spring; sockeye; and coho salmon.

Alaska fishermen have fought long and bitter fish wars over how these salmon are allocated between competing interest groups. And for much of that time, hatchery critic Nancy Hillstrand contends, hatchery salmon production might have been significantly reducing the number of salmon for all interests.

“Invisible allocation” is what  Hillstrand, a Kachemak-Bay fish processor, calls it. She has joined with the KRSA, outdoor and conservation groups, and the commercial fishermen petitioning the board.

Emergency petition

The latest petition takes clear aim at the keys issues that left the earlier petition high-centered:

“Where one must weigh the risk to sustainability of the state’s wild stocks of salmon against the private investment,” the revised petition says, “the law is clear; wild stock integrity comes first.”

Some fisheries biologists working for the state having been making that argument for years, but their battle has been largely a bureaucratic guerilla war fought in an agency where commercial fishing interests hold considerable power.

Commissioner of Fish and Game Sam Cotten is a former commercial fisherman, the father of two active commercial fishermen, and a former member of the board of an aquaculture association. He has, however, refused to recuse himself from hatchery discussions.

State biologists blew the whistle on the largest group of  private, non-profit hatcheries in 2009, reporting “an extensive record of on-going problems. Despite ample opportunity and encouragement to address these issues, PWSAC (Prince William Sound Aquaculture)  had neither corrected nor explained most of these on-going problems.”

The review found that four  Sound hatcheries “exceeding permitted stocking levels; (maintaining) substandard broodstock to egg take survival rate; withholding data required in permits; conducting cost-recovery harvest outside Special Harvest Areas without emergency order authority; and refusing to fund required monitoring.”

And those were just the major problems the biologists found. The list of significant but less problems was even longer: “Cost recovery shortfalls; large-scale straying and refusal to participate in straying evaluation; roe-stripping associated with excessive broodstock collections; inadequate reporting of roe sales; chum salmon otolith marking program failures; erratic management recommendations; lack of good faith negotiations; cooperative agreement problems; failure to report hatchery production/operational problems; unwieldy and unbalanced (non-profit) board structure; lack of individual accountability among corporate officers and PWSAC board of directors members; and
department failure to enforce compliance with permits, annual, and basic management plans.”

There is no indication much of anything changed in the wake of the detailed, 207-page report.

 

 

 

 

 

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