News

Got fish

2016-06-26 12.47.44

Copper River sockeye salmon stopped short of the Gulkana hatchery/Craig Medred photo

After a long summer of weak, sockeye salmon returns around the northeast Gulf of Alaska, a late surge of the fish into the Copper River has provided good news for the Cordova-based Prince William Sound Aquaculture Corporation (PWSAC).

The private-nonprofit (PNP) business now has adequate numbers of eggs with which to seed a pioneering state hatchery it  manages along the banks of the Gulkana River, a major clearwater tributary to the glacially turbid Copper. 

Continuing the unpredictable behavior of 2018 sockeye, however, the fish didn’t show up exactly where expected. Instead of swarming the creek beside the hatchery just upriver from the near-deserted community of Paxson, about 300 miles northeast of Anchorage, the fish for a time disappeared.

As the days of August turned into September with few fish in the creek outside the hatchery, fears began to rise that the salmon might not show. But PWSAC eventually found enough of them trying to make their way into Crosswind Lake about 50 miles southwest of the hatchery to come close to the company goal of 30 million eggs for the Gulkana hatchery.

PWSAC General Manager  Casey Campbell is reporting the company was able to collect 28 million eggs, primarily from Crosswind sockeye. It appears the bulk of Gulkana sockeye turned left at the West Fork instead of continuing up the Middle Fork, crossing Paxson Lake and heading for the hatchery.

Crosswind Lake – the Alaska version of a salmon farm – is at the head of Dog Creek, a tributary to the West Fork deep in the Copper Basin wilderness.

No-home home

Alaska decades ago blocked the production of pen-raised salmon (although the state invests in them), but then proceeded to become the North American leader in the production of hatchery salmon.

Under state supervision, PWSAC turned Crosswind Lake into a giant sockeye nursery to raise fish for what Alaska calls an “ocean ranching” program.

“There is negligible salmon spawning habitat at Crosswind Lake, and no natural production escapement (spawning) goal has been established,” a state management plan notes. Before PWSAC started air dropping sockeye fry into the lake in the mid-1980s, Crosswind supported only a small number of sockeye.

The population has been boosted incredibly over time. With the annual stocking of sockeye up to 10 million fry per year in the 2000s, adult sockeye came swarming back to the lake at numbers ranging from 90,000 to a 2016 high of 490,000, according to PWSAC.

Enough fish were returning by the end of the 2000s, according to a 2009 report from Fish and Game, that the combined runs from Crosswind and other lakes boosted by Gulkana hatchery fish “complicates harvest and wild stock management in the Copper River District.”

Copper River sockeye are caught in a mixed-stock commercial fishery off the mouth of the river, and in mixed-stock subsistence and personal-use dipnet fisheries in the river. Fishery biologists worry that heavy fishing effort focused on large runs of hatchery fish can lead to the over-harvest of wild fish in mixed-stock fisheries.

Wild runs to the Copper River basin this year were weak. Commercial fisheries were closed early and stayed closed for most of the summer. Subsistence and dipnet fisheries were restricted, but later reopened as returns improved.

Exactly how many salmon escaped fishermen and made it to Crosswind is unclear, but big numbers there are really more of a problem than anything else because the fish have almost nowhere to spawn.

The state established what it calls a “special harvest area” to allow PWSAC to harvest fish for cost-recovery at Crosswind, but flying fish out of a remote lake is costly. So the state also gave the commercial-fisherman run company an out if it can’t make money on Crosswind sockeye.

“If PWSAC is unable to harvest the surplus hatchery-produced sockeye salmon in the special harvest area, they will, under authority of ADF&G, destroy all sockeye salmon in excess of broodstock and escapement needs,” the state management plan says. “Disposal of these fish is undesirable; however, allowing them to escape into Crosswind Lake is also problematic. Excess destroyed sockeye salmon will be left in the stream below the weir in the special harvest area.”

On occasion in years past this has been a problem, but this year the lake originally stocked with Middle Fork Gulkana sockeye has turned out to be a lifesaver for a hatchery that can’t hatch any young fish if it can’t find any eggs.

Ranching the ocean

By Alaska ocean-ranching standards, the manmade return to Crosswind, as well as the entire return driven by the unique Gulkana hatchery operation, is small potatoes. But it is now being watched more closely than in the past because of concerns about Alaska wild-salmon stocks.

Alaska started a state-run hatchery program in the 1970s with salmon runs faltering due to poor management and cold North Pacific Ocean waters that suppressed survival at sea.

“In 1974, the Alaska Legislature expanded the hatchery program, authorizing private nonprofit corporations to operate salmon hatcheries,” according to a Fish and Game history. “Alaska’s salmon hatchery program developed under this authority and was designed to supplement—not replace—sustainable natural production.”

By the end of the 1970s, Alaska hatcheries were seeding the North Pacific with 100 million young salmon a year. Production slowly ramped up at first and then began to skyrocket at the start of the 1980s. By the end of that decade, stocking was up above 1 billion young fish, and the state was feeling the burden of costs associated with raising hatchery fish.

Most state hatcheries were then turned over to the PNPs, which were able to tax commercial fishermen and operate their own “cost-recovery fisheries” to pay for hatchery operations.

To benefit commercial fishermen and the commercial fish processors, the state now allows the PNPs to collect about 2 billion salmon eggs per year, fertilize them, hatch them, grow them briefly and then dump 1.5 billion to 1.7 billion young salmon per year into Alaska coastal waters.

Only a small percentage make it back, but those 50 million to 100 million adult fish are worth upwards of $150 million per year, according to the Alaska Department of Fish and Game.

About 78 percent of them are caught by commercial fishermen, according to the 2017 Annual Salmon Fisheries Assessment Annual Report, and another 17 percent are scooped up by hatcheries to cover their operating costs. 

Of the 5 percent left, four percent are used for broodstock to produce more salmon, left to spawn naturally or among “unharvested returns.” About 1 percent of the fish are split between subsistence, personal-use and sport fishermen.

In the 10-year period from 2008 to 2017, the hatchery returns averaged 64 million salmon a per year, according to Fish and Game statistics. Seventy-four percent – about 47 million – were low-value pink salmon.

High-value sockeye, despite efforts to turn lakes like Crosswind into high-volume nurseries, accounted for only 4 percent of the return or 2.2 million fish. Hatchery production levels for prized coho and Chinook salmon were even less with 1.3 million coho and only 100,000 Chinook.

Chum salmon, nearly all of which are harvested in commercial fisheries accounted for the other 20 percent of the catch, and a big chunk of the value. Chums and pinks are the easiest salmon to ranch because they spend only one winter in fresh water.

Other species need to spend two or more years in a river or lake, thus the need for a nursery like Crosswind.

The 25 PNP hatcheries have, in general, been a big benefit to commercial fishermen and communities near where the hatcheries operate, but with hatchery salmon catches high and returns of wild salmon – particularly sockeye and Chinook – declining around the north Gulf Coast and in the Alaska Panhandle, questions are beginning to be raised about whether the 49th state has stumbled into that problem fishery managers sought to avoid:

Supplement, not replacing, sustainable natural production.

There is no evidence the Gulkana hatchery started long ago at a minimal costs has harmed wild Copper River stocks, but a study conducted as part of ongoing research into the consequences of the 1989 Exxon Valdez oil spill stumbled on evidence that at high levels of production, pink salmon from Prince William Sound hatcheries were suppressing Copper River sockeye numbers.

Copper River sockeye and king salmon are Alaska’s most valuable salmon. Lower 48 chefs pay insane amounts of money for the first-of-the season Copper catches. Whether hatchery operations played a role in this year’s weak return is unknown, but the Alaska  Board of Fisheries is to discuss that issue again next week.

 

 

 

 

 

 

 

 

Advertisements

23 replies »

  1. The Gulkana River sockeye are comprised of several stocks (mixed stocks) that have all imprinted to the unique chemical signature of their birthplace (stream). The sockeye that to go to the West Fork, Middle Fork, and upper Gulkana are all different stocks and have imprinted to different tributary chemical signatures. All these unique stocks of the Gulkana River, don’t decide to just turn left up the West Fork. The large numbers of adults that returned to West Fork, Crosswind Lake, were fish that were stocked/natal to Crosswind Lake and imprinted to it. Yes, there is a small amount of straying in salmon stocks, but the rates are low. The Crosswind hatchery stock had high
    survival and the other wild stocks had poor survival.

    Like

      • I suspect we don’t know 100% but that scenario you suggest is such an abnormality that it would not be suspected. Clearly, unless there was reason to believe something like that had happened the assumption would be that they are just Crosswind hatchery stock (and that’s because of the straying of salmon rates being low like Tim says).

        Like

    • at least that’s what we want to believe, Tim.

      straying rates in salmon are highly variable. it could be wild returns were better than we thought, but that somehow a bunch of wild fish got decoyed to Crosswind.

      “While there is concern that strays from hatcheries will influence wild gene pools, wild salmon may also stray into a hatchery. Nicholas and Van Dyke (1982) estimated that 2,022 (64.7%) of the 3,124 wild coho salmon returning to the Yaquina River watershed in 1981 entered the Oregon Aqua-Foods hatchery. Such decoying of wild salmon into hatcheries both reduces the number of wild fish in the stream and contributes to genetic mixing.” https://www.nwfsc.noaa.gov/publications/scipubs/techmemos/tm30/quinn.html

      why would the possibility for decoying to Crosswind be any different?

      and there’s some new research out there “indicating salmon stray less in years of greater abundance.” or, to flip that around, they stray more in the years of lesser abundance.

      https://mail.google.com/mail/ca/u/1/#search/herd/FMfcgxmZTvLxMvfcJTdDHwWVmzqcdWJC?projector=1&messagePartId=0.1

      the weir count on the Gulkana, of which i admit i’m skeptical, would make this a year of significantly lesser abundance. could that alter how fish behave?

      “….two river branches might have very similar chemical composition, and distinguishing between them could be difficult (Dittman and Quinn 1996). Larger groups of fish are better able to sense odourcues (Lenwood et al. 1982; McNicol et al. 1996).

      “Salmon likely experiences selective pressure to group for a variety of reasons, including protection from predation.”

      so could a significant number of wild fishing looking for the protection of the school get decoyed to Crosswind? i don’t know.

      but it’s certainly possible. there’s a lot more we don’t know about salmon behavior than we think we know. but we do know for certain is that the idea that all salmon predictably return to their release sites is hogwash.

      Like

      • Craig, the straying thing is a hard thing to get a handle on (both wild and hatchery). I know of several thousand Main Bay sockeyes that were caught in the seine fishery in Icy Straight. Unlikely those fish were just meandering before heading back outside and North to PWS. These things occur, for whatever reason, but one thing we do know about them is that they are extremely difficult to predict.

        Like

  2. Good question Bill. I do know one season so many reds came back, to Crosswind, and the weir stopped them from going into the Lake. The spawning fish attracted numerous bruins, that had a great feast.
    Gary at Gulkana is the man to ask, this question, he has been hatchery mgr for over 25 years.

    Like

  3. Years ago, many biologists in Alaska expressed concern over the hatcheries built by the State, then essentially given to the aquaculture associations. The State initially tried to increase sockeye numbers, because of the value of that species in the harvest. Unfortunately, the disease IHNV wiped out any gains in sockeye production, afflicting virtually every sockeye hatchery. The hatcheries that have been successful have been largely the pink salmon hatcheries, for reasons noted in the article. In general, sockeye hatcheries in Alaska have been a bust.

    But, all those pink salmon sub adults have to eat something while they’re out there in the ocean. Are they competing with wild stocks of sockeye, king, silver and, yes, pink salmon, for limited available food resources?

    Nobody knows for certain at this point. But there are things going on with wild stocks that nobody can explain just yet. But, based on past experience with sockeye hatcheries in Alaska, the Gulkana hatchery May be overdue for an IHNV outbreak.

    Mike Vivion

    Like

    • Pretty clear that you haven’t studied PSWAC sockeye hatcheries, Mike. Main Bay hatchery and Gulkana are entirely different kinds of hatcheries but they both have been very successful for a long time.
      Anything is possible but I suspect they are both successful because they’ve got a handle on IHNV.

      Like

  4. Craig, is Crosswind Lake the same one the Copper Basin 300 travels over midway between Sourdough and…I don’t remember the name of the checkpoint? Wolverine, maybe. Been a while since I was in that country.

    Like

  5. I believe it was Crosswind lake that remote releases of sockeyes were stopped primarily because of the complaints from cabin owners on the lake. They were experiencing large numbers of Brown bears tearing up their cabins-they said they had not experienced that prior to those releases.

    Like

    • it’s an interesting situation. it would be nice to have a whole lot more data on Copper River sockeye. the sonar showed a lot of fish late this year, but where they went is still unclear.

      everyone thought they were the Gulkana fishery, but that doesn’t appear to be the case although PWSAC scraped together enough sockeye for brood stock, an activity that usually takes them a few days at the hatchery and this year took them about a month with the trip to Crosswind to find the bulk of the fish.

      strange, strange year.

      Like

      • the sonar showed a lot of fish late this year, but where they went is still unclear. could the fish going by the sonar be alot of slivers? I don’t think the sonar data can separate out reds from slivers.

        Like

      • it can’t. but i know people who were over there dipnetting in August after the sonar was shut down, and judging from the what they had to say – they caught a lot of barely blushed sockeye – it would seem the fish that came before August were sockeye.

        and i talked to people who were over there looking for silvers in late August and still getting sockeye.

        Like

      • If you don’t mind Al, how long do I need to boil moose hooves in order to remove them from the foot? Thanks.

        Like

      • Bill, i don’t have an time for you. The last hooves i removed were caribou. i use a coffee can and hot plate. it took like a hour after the water got going.

        Like

      • Al, do you mean silvers, not slivers?
        Anyway, the ADF&G sonar, below Miles Lake is pulled, at the end of July every season.
        The Coho (silvers) return from Copper River Delta, start showing up around August 7th and continues into October.

        Like

      • Thanks Al.
        James, do you remember the argument that Crosswind lake remote sockeye releases were objected to by cabin owners there feeling the increased brown bear populations were reasons their cabins were being damaged. My recollection was that the remote releases were stopped but evidently they were able to start up again by putting in a weir to keep adult sockeyes from entering the lake. Was there some sort of compromise between PSWAC and those cabin owners that got the releases started up again?

        Like

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google+ photo

You are commenting using your Google+ account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s