In the strange, pandemic world of today, one of the unintended victims of the coronavirus COVID-19 could be the regularly and often loudly stated danger of “over-escapement” of salmon into Alaska streams and rivers.
Commercial fishermen, especially those fishing Cook Inlet at the front door of Anchorage, have long claimed threats of environmental damage from salmon crowding state waterways in arguing for increased commercial catches to put more money in their pockets.
The United Cook Inlet Drift Association (UCIDA) even went to court to force federal officials to take over management of Inlet salmon because of state actions the organization argued were causing “environmental and economic injuries related to over-escapement,” as court documents put it.
The over-escapement theory is simple. It goes like this:
If too many salmon escape the nets of commercial fishermen, they plug streams and rivers with their bodies and some die before spawning. But the successful spawners still produce so many young that the mass of them competing for food means more death for salmon fry and results in the survivors going to sea as smaller and weaker smolts, which are also prone to die.
The belief is that the ultimate, end result of all of this is that fewer salmon survive to return to spawn as adults.
And fisheries biologists generally agree over-escapement can reduce a river’s “yield” in much the same way that over-planting a potato patch can reduce the production of tasty tubers. There is a significant difference between potatoes and salmon in that the latter suffer huge variations in survival at sea that make yield harder to calculate, but the theory is much the same.
Commercial fishermen have, however, pushed over-escapement way beyond a yield issue.
“Over-escapement is not a myth. Whether escapement goals are exceeded or escapement goals are set too high, salmon populations are at risk when they exceed the carrying capacity of the habitat.”
The region’s most powerful fishing lobby has repeated this claim so many times that some in Alaska now believe over-escapement does put salmon populations “at risk.” The belief is so widespread that a couple of the top fisheries researchers in North America this week moved to stick a fork in it.
It is a myth
“Concern that the Bristol Bay sockeye salmon fishery represents a substantial public health risk has prompted requests for severe restrictions or even complete closure of the fishery until the threat of COVID-19 has passed,” University of Washington scientists Daniel Schindler and Curry Cunningham wrote in a commentary published in National Fisherman magazine on Tuesday. “…These discussions have generated widespread concern about ‘over-escapement’ – that severely restricted fishing would result in spawner abundances (escapements) beyond what watersheds can withstand, thereby severely depressing future salmon production.”
Bristol Bay is home to Alaska’s most profitable salmon fishery. The fourth-largest run in Bay history was worth a record $306.5 million to fishermen last year, according to the Alaska Department of Fish Game.
The catch this year – if there is a fishery – is unlikely to come close to that given the difficulties of ramping up any food processing business in the middle of a pandemic with an indeterminate end. This has fueled over-escapement fears, but Schindler and Cunningham said there is no reason to worry.
Neither the last 60 years of data on human harvests of sockeye salmon in the Bay nor the prehistoric record support the idea that not fishing will seriously harm salmon runs.
“The myth of over-escapement is an unnecessary distraction and should be dropped from these discussions,” they wrote. “The fish will be just fine no matter what the outcome is for the 2020 season.”
The best argument that the fish can survive without being caught is recorded in the beds of Bristol Bay lakes.
Reconstructions of unfished, prehistoric salmon runs based on nitrogen isotopes decaying salmon carcasses left behind in lake beds “show that the sustained abundance of salmon prior to the development of commercial fisheries was comparable to the abundance (the sum of catch and escapement) observed over the last few decades,” the scientists observed.
A state study more than a decade ago reached conclusions similar to those of Schindler and Cunningham, but state biologists were able to find three cases in which “returns per spawner fell below replacement for two to five years following consecutive over-escapements that were greater than twice the upper escapement goal range.
“These observations were consistent with results from whole lake experiments that have shown that overgrazing by large fry populations for 2 or more consecutive years caused the highest level of restructuring of zooplankton populations and the slowest recovery time. However, as seen in the review of salmon stocks in British Columbia, we did not observe long-term stock collapse of any of the 40 stocks that could be attributed to
The real issue
The serious Bay issues needing attention, Schindler and Cunningham added, are not biological but economic and social as is the case in fisheries across the state be they commercial, sport, subsistence or personal-use. The scientists expressed hope that plans could be developed to allow for fishing in the Bay while minimizing the risks the infectious disease poses to humans.
“The collective creativity of our communities is in high gear, developing scenarios and their associated risks for how a fishery might operate without compromising public safety,” they wrote. “The social and economic costs of severely restricting the fishery are enormous, and any decision to do so needs to be balanced against the public health risks that fishery operations pose to local communities and fishery participants.”
State officials are still weighing the interrelated issues of health risks, health consequences and possible protective measures. One of the problems in the Bay is that the fishermen are old.
“Currently, 26 percent of non-resident permit holders in the drift fishery are over the age of 60,” Jesse Coleman at the University of Alaska Fairbanks reported in an August study.
Non-residents make up 55 percent of the fishermen in the Bristol Bay drift net fleet, and another 26.5 percent of the fleet journeys to the Bay from elsewhere in Alaska to fish during the short summer season, according to the state Commercial Fishery Entry Commission.
The average age of Alaska resident fishermen is even older than that of the non-resident permit holders, according to Coleman’s study. That would put somewhere around a third of the drift fleet – or more than 620 fishermen – in the COVID-19 threatened, over-60 age group.
Data on the disease from around the world indicates older people are in no greater danger of catching COVID-19 than younger people, but if old people do catch it they are in significantly more danger of dying.
The global data show case-fatality rates accelerating with age with the big jump generally coming for those over 60 or already compromised by obesity, heart disease, diabetes or a variety of chronic illnesses.
Many of Alaska’s older commercial fishermen, having spent more time in the skipper’s chair than that health club, are not exactly pantheons to the value of fitness. The coronavirus could well pose more of a threat to them than to the Bay residents who want them to stay away, but many fishermen are not the sort to worry about such things.
Given that, the most worrisome concern in the Bay might be that if fishermen get sick and require hospitalization, they suddenly become someone else’s problem, and the region’s medical facilities are very, very limited.
The “seasonal influx of thousands of harvesters and workers from around the world, starting in May, represents a substantial risk for introducing COVID-19 to remote communities – where it has yet to be detected, and where people are particularly vulnerable and medical resources are distinctly limited,” Schindler and Cunningham wrote. “Further risks are associated with the often crowded conditions aboard fishing vessels and in fish processing facilities that create perfect conditions for the rapid spread of COVID-19.
“…It is clear that concerns for the negative ecological impacts of exceptionally high escapements should be dismissed. Instead, decisions should focus on balancing human health risks and economic impacts.”