December 19, 2023 — The health benefits of eating seafood are appreciated in many cultures which rely upon it to provide critical nutrients vital to our physical and mental development and health. Eating fish and shellfish provides significant benefits to neurological development and functioning and provides protection against the risks of coronary heart disease and Type 2 diabetes.
Sea temperatures’ impact on salmon species explored in 2023 Arctic Report Card
December 18, 2023 — In December 2006, I sat in a similar carpeted room in this city and listened to scientists talk about an Alaska-size chunk of sea ice that was no longer floating on the northern oceans compared to previous years.
That meant that the “refrigerator of the northern hemisphere” was much less powerful than it had been in recent decades, said Mark Serreze, director of the National Snow and Ice Data Center in Boulder, Colorado. That failing fridge is part of the reason our world has become warmer.
This week, scientists here at the Fall Meeting of the American Geophysical Union rolled out their 18th version of the Arctic Report Card, a series of essays and data about environmental changes on top of the world put together by people at the National Oceanic and Atmospheric Association and featuring the work of many Alaska scientists.
High-value US West Coast stocks may migrate out of reach due to climate change
December 17, 2023 — Recent NOAA research forecasts that three high-value groundfish species will migrate toward deeper offshore waters along the United States West Coast due to climate change in the near future, which will likely require fishery managers to adapt their strategies in response.
NOAA’s study, “Species redistribution creates unequal outcomes for multispecies fisheries under projected climate change” was published in the peer-reviewed journal Science Advances in August 2023. It shows that sablefish, dover sole, and shortspine thornyhead are projected to migrate to deeper offshore waters, posing challenges for fishers that may need to travel longer distances and fish at greater depths or shift their operations completely to target more accessible species.
Alaska salmon woes, extreme precipitation, tundra shrub growth part of Arctic transformation
December 14, 2023– The collapses of Western Alaska salmon runs have been among the most consequential climate change impacts in the rapidly warming Arctic over the past two years, according to an annual report assembled by a federal agency.
The 2023 Arctic Report Card, released on Dec. 12 by the National Oceanic and Atmospheric Administration (NOAA), includes a special chapter on Alaska salmon among its updates to sea ice, air temperature, and permafrost conditions in a region of the world that is warming up to four times as fast as the global average.
Western Alaska salmon runs provide a “particularly clear picture” of how ocean warming affects ecosystems, said Daniel Schindler, a University of Washington fisheries expert who was a contributing Arctic Report Card author.
Climate change in Alaska is not simply something expected in the future, said Schindler, who spoke Dec. 12 at a news conference held at the American Geophysical Union’s annual gathering in San Francisco, California.
“It’s happening now. It’s been happening for decades. Whether you’re talking about fish or people or birds, there are real impacts that we need to deal with right now,” Schindler said.
Rick Thoman, of the Alaska Center for Climate Assessment and Policy at the University of Alaska Fairbanks (UAF), delivered a similar message at the news conference.
“As Alaskans, as people of the Arctic, we are living this change every day. We have no choice, no choice at all, other than to work with what is happening,” said Thoman, one of the Arctic Report Card editors.
New salmon habitat created by melting glaciers could be threatened by mining claims, study finds
December 14, 2023 — Thousands of salmon on the West Coast of North America are finding their way into new streams left behind as glaciers retreat. But a new study suggests mining companies are too keen on the newly exposed mineral deposits beneath the shrinking glaciers — and few policies are in place to protect the emerging habitats.
The paper led by researchers from Simon Fraser University, the University of Montana, Taku River Tlingit First Nation, and Gitanyow First Nation Hereditary Chiefs highlights a broad global challenge as many environmental policies struggle to keep pace with climate change.
Just a couple decades after some new streams were created, researchers have found thousands of fish, said Jonathan Moore, the lead researcher on the paper and a professor at Simon Fraser University. Salmon have evolved through dynamic landscapes with glaciers’ ebbs and flows and are specially equipped to find new habitats where they can flourish.
Most North American salmon watersheds or regions are being influenced by contemporary glacier retreat. These glaciers are rapidly declining in volume, thickness and area, accelerated by recent human-caused climate warming. About 60% to 100% of glaciers are predicted to disappear from western Canada by 2100.
As glaciers shrink, some of the streams they feed will become warmer, flows depleted and salmon will become stressed and in some situations die.
Although the loss of glaciers will decrease water storage nd cooling capacity that threatens people and aquatic ecosystems downstream, researchers have found that some glacial retreat will leave behind thousands of miles of new salmon rivers over the coming decades in western North America.
Overall, the net effects of glacier retreat on salmon will likely depend on the phase of glacier retreat, the traits of salmon species, and local environmental, geographic and ecological characteristics of watersheds.
5 signs the Arctic endured a record-hot summer
December 13, 2023 — This past summer was the hottest on record in the Arctic, which is warming nearly four times faster than any location on the planet. And the symptoms of that warming laid bare a rapidly changing region that in many ways barely resembles what it once was.
Key data points show that the Arctic continues to become less icy, wetter and greener, according to a report card released by the National Oceanic and Atmospheric Administration on Tuesday. The trends, all linked to a warming climate, have been observed for decades.
And they played out in dramatic ways this summer: Out-of-control wildfires forced entire communities to evacuate. A river surged from its banks and into homes because of dramatic glacial thinning. Near the peak of Greenland’s ice sheet, more than 10,000 feet above sea level, temperatures soared above freezing for only the fifth time on record.
Even amid rapid change, variability of weather patterns meant a few parts of the Arctic still exhibited some of the frigid norms of the past. For example, sea ice persisted for much of the summer in the East Siberian Sea, and a colder-than-normal spring slowed the melt of sea ice and snow cover in Alaska.
But the broader picture makes clear that the Arctic continues to change, with the past 17 years accounting for the 17 smallest annual minimum sea ice covers in the 45-year satellite record. This year, sea ice cover ranked sixth smallest, amid summer temperatures that were the Arctic’s hottest on record and a year that ranks sixth warmest.
Study shows connection between recent marine heatwaves and Western Alaska chum salmon declines
December 6, 2023 — For newly hatched Western Alaska chum salmon, there is no time to waste when it comes to making their way to the open ocean. The tiny fry begin their journey from their natal streams just days or weeks after being born. When they finally reach the Bering Sea, sometime from mid-June to mid-July, their priority becomes consuming marine prey and building the energy reserves that will carry them through their first winter. Throughout their years in the ocean, the Western Alaska chum will travel extensively between the Bering Sea and the Gulf of Alaska.
Unfortunately, simultaneous warming trends in the Bering Sea and the gulf appear to have come as a double whammy for Western Alaska’s juvenile chum salmon. A new study by scientists from the National Oceanic and Atmospheric Administration (NOAA) and the Alaska Department of Fish and Game shows a possible link between a period of exceptionally warm ocean temperatures and chum crashes seen across Western Alaska.
“Loss of sea ice is having an impact on various ecosystems. And so with warming we’re seeing a change in the food web,” said Ed Farley, lead author of the study and head of NOAA Fisheries Ecosystem Monitoring and Assessment Program. “That food web is less energetic. It’s poorer-quality prey. And it’s impacting juvenile salmon, especially juvenile chum salmon in the northern Bering Sea. It’s impacting their fitness prior to winter.”
By “poorer-quality prey,” Farley primarily means jellyfish, also known as cnidaria. Jellyfish have been shown to proliferate when ocean temperatures warm.
“There are more cnidaria in the ecosystem of the Northern Bering Sea during warm years, but there was significantly more during this most recent anomalously warm period,” Farley said.
Ecological Forecasts Offer New Insight into Changing Conditions that Can Shift Fisheries, Drive Conflicts
December 6, 2023 — Weather forecasts only look out a few days to weeks. Two new research studies describe the increasing accuracy of specialized scientific models in forecasting changes in the ocean up to a year in advance.
The models have increasing value as climate change drives shifts in ocean temperatures and other conditions with new and unexpected outcomes. The changes can have ecological and economic repercussions. For example, warming ocean temperatures increase the overlap between fishing fleets and protected species like whales and sea turtles, which can trigger fishing closures. The research was conducted by scientists at NOAA Fisheries and University of California, Santa Cruz.
NOAA Fisheries is also pursuing development of “Climate-Ready Fisheries” that adjust to changing conditions, even over the course of a single fishing season. Some forecasts examined in the new studies could provide insight as much as a year in advance. This could highlight potential conflicts or opportunities in time for managers and fishermen to do something about them. This kind of proactive management was highlighted in the recent National Climate Assessment as an important approach to addressing the impacts of climate change.
“We can now look months or even a year out and ask, what is that part of the ocean going to look like, and what does that mean for the species and for the people and industries who use it?” said Stephanie Brodie, lead author of one of the new studies. “For fisheries, it gives managers a chance to evaluate the trade-offs in reducing human-wildlife conflict and supporting an economically viable fishery.”
Where Will the Whales Be? Ask the Climate Model.
December 5, 2023 — The opening of California’s commercial crab season, which normally starts in November, is delayed once again to protect humpback whales foraging for krill and anchovies along the coast.
This region of the Pacific has been under the grip of a marine heat wave since May. “The Blob,” as this mass of warm water has become known, is squeezing cooler water preferred by whales and their prey close to shore, where fishermen set their traps.
This crowding can lead to literal tangles between whales and fishing equipment, endangering the animals’ lives and requiring grueling rescue missions.
In a new study, scientists say they can now use global temperature models, commonly used in climate science, to predict up to a year in advance when hot ocean temperatures raise the risk of whale entanglements. This lead time could allow state regulators, fishermen, and other businesses that depend on the fishery — as well as Californians hoping for a Dungeness crab holiday meal — to plan ahead for potential fishing restrictions.
“It really just helps give a lot more information and reduce some of that uncertainty about the future,” said Steph Brodie, lead author of the study published Tuesday in the journal Nature Communications. Dr. Brodie is currently a research scientist at Australia’s national science agency, but conducted this research while working at the University of California Santa Cruz and the National Oceanographic and Atmospheric Administration.
Study points to concurrent marine heat waves as culprit in Western Alaska chum declines
December 5, 2023 — Successive marine heat waves appear to have doomed much of the chum salmon swimming in the ocean waters off Alaska in the past year and probably account for the scarcities that have strained communities along Western Alaska rivers in recent years, a newly published study found.
In the much-higher water temperatures that lingered in the 2014-19 period, juvenile chum salmon metabolism was super-charged, meaning they needed more food, said the study, by scientists with the National Oceanic and Atmospheric Administration and the Alaska Department of Fish and Game. But the food that was available was of low quality — things like jellyfish instead of the fat-packed krill and other prey they normally eat, the study said.
That means for the juvenile salmon trying to survive their first year at sea, “there’s not much gas in the tank,” said the study’s lead author, Ed Farley, manager of NOAA Fisheries’ Alaska Ecosystem Monitoring and Assessment Program.
Juvenile chum salmon that swam from spawning areas in the rivers suffered what was essentially a double hit, said Farley, who works in the NOAA Fisheries Auke Bay Laboratories in Juneau. They encountered one extreme heat wave in their critical first summer when they were in the northern Bering Sea and then, when they entered their wintering grounds in the Gulf of Alaska, swam into the tail end of another extreme heat wave, he said.
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