KDLG 670AM | By Isabelle Ross
Published July 15, 2022 at 2:19 PM AKDT
Bristol Bay’s 2022 sockeye run is now the biggest on record: 69.7 million fish have returned this summer. That surpasses the previous record of 67.7 million fish, which was set last year.
More than 3 million sockeye have swum up the Wood River to spawn in the tributaries around Lake Aleknagik, about 20 miles from Dillingham, according to the state’s counting tower on the river. Sherol Mershon lives along the lake near the head of the river. She owns a bed and breakfast there and has hung commercial fishing nets for 45 years. She said this year’s runs are remarkable.
“They just pour by. Sometimes there’s 500 in the air, breaking the water. When it’s dead calm you can see really well,” she said. “I lay in my bed at night with the window open and I can hear them jumping, and it’s just amazing. It’s absolutely beautiful.”
The east side of Bristol Bay has seen robust sockeye returns as well. Shaelene Holstrom grew up in Naknek and returns each summer to subsistence fish.
“I have been enjoying hearing how everybody is catching and how it’s just been crazy processing and running all over the place, trying to figure out what to do with fish,” she said. “I think that’s a great feeling, cause then we know we’re getting our numbers up at the river, and that warms my heart.”
Huge commercial harvests
Bristol Bay’s commercial fleet hauled in the most fish on record this year. Fishermen in the Nushagak, one of the bay’s five commercial districts, harvested more than 2 million sockeye in one day this season.
William P. Johnson just finished his sixty-second year as a boat captain. He grew up set net fishing near Igushik in the 1940s with his family. After more than six decades of fishing, he wasn’t phased by the large returns this season.
“Our goal was to get at least 100,000 [pounds]. We exceeded that, and so we came home after our last delivery on [July] 12th,” he said.
For thousands of years, Yup’ik, Alutiiq and Dena’ina peoples have presided over Bristol Bay. The commercial fishery began in 1884, as outsiders came to the region and built canneries. The federal government managed the fishery until the state took over in 1960. Johnson believes that change was an improvement.
“I think the local control by our local Fish and Game department has a lot to do with the improvement of the resource that we participate in,” he said.
Johnson, who also fishes for subsistence, said the large sockeye runs haven’t changed how much food he and his family put away for winter.
“There has never been any problem for us in getting our fish,” he said. “But one thing that has been impacted is that king salmon seem to have declined.”
As sockeye abound, Chinook and chum runs decline
While sockeye have returned in droves, Chinook and chum salmon runs have dropped. Scientists don’t know why that is, either.
Dan Schindler is a professor of aquatic and fisheries sciences at the University of Washington. He has studied sockeye on the west side of Bristol Bay for decades and says the exact reasons for why the bay’s sockeye runs are so huge will probably always remain a mystery.
“In terms of what the mechanism is, it’s really hard to really pinpoint that,” he said. “What we have is correlations. And the correlations are that when we’ve had really warm — to hot, even — eastern Bering Sea sea surface temperatures, Bristol Bay sockeye have done really well. And other species in the region haven’t,” he said.
There are slight differences in how these fish behave.
“We know they eat slightly different things in the ocean. They migrate to the ocean at slightly different times during the season. They probably have slightly different behaviors in the ocean,” Schindler said. “All of those things are making Chinook and chums vulnerable to something that sockeye aren’t — at least sockeye that are returning to Bristol Bay.”
Sockeye runs to rivers in other parts of the state have struggled; returns along the Gulf of Alaska have performed poorly over the past decade.
“I suspect it’s something to do with ocean temperatures causing some change in the food web — that smolts leaving the west side of Bristol Bay are hitting really excellent conditions for survival, whereas smolts leaving places like Chignik and the Copper River are hitting ocean conditions that have been really poor for smolt survival,” Schindler said.
Warming oceans and lakes coincide with big Bristol Bay returns
River systems on the west side of Bristol Bay have seen an especially large sockeye boom over the past few years.
“All the way up along the west and north side of Bristol Bay all the way to the Kuskokwim. So something anomalous has happened here. And it has coincided with some of the warmest ocean temperatures ever observed in the eastern Bering Sea and in the Gulf of Alaska,” Schindler said.
Warming waters at the spawning grounds likely also affect their growth, he said.
“As the lakes have warmed up, we see more plankton in the lakes, and of course the plankton are the food for juvenile sockeye,” he said. “So over the last 60 years, we actually see that juvenile sockeye are growing much faster now than they were 30 or 40 years ago, which means they’re leaving for the ocean as bigger smolts. And presumably, that has something to do with their higher survival rates in the ocean.”
The sockeye runs now returning to Bristol Bay may be the largest of the past several hundred years. Schindler and other scientists have attempted to reconstruct how big the bay’s runs were centuries ago.
“Salmon coming back from the ocean bring back a distinctive marine nitrogen isotope signature, which we’ve used to reconstruct how many sockeye were spawning in places like the Word River and the Kvichak and throughout the Togiak refuge over the last thousand years or so,” he said.
This is called paleolimnology, where researchers take the mud out of the bottom of lakes and scan that sediment for an isotope, Nitrogen-15. Schindler said even with commercial exploitation of the sockeye populations, the recent runs have returned at historically high rates.
“If you add up the catch and escapement that we’ve observed in the last 25 or 30 years, the sum of those two numbers appears to be higher than the number of fish that ever returned to these lakes in the last 500 to 1,000 years,” he said. “And while that might seem surprising, it really does support what we’ve seen with our real time data over the last 50 or 60 years that climate warming has actually made these lakes more productive than they were 100, 200, and 300 and longer — 400 years in the past.”
The total run is now 69.7 million sockeye, but the season isn’t over yet. Fish and Game forecast a run of 75 million fish, but it could go as high as 90 million this summer.
Mackenzie Mancuso conducted an interview with Shaelene Holstrom which was used in this story.