Alaska
Genetic diversity in Alaska’s red king crab may provide climate change resilience
New genetic research on the Alaska red king crab reveals previously undiscovered diversity among different regions, suggesting the species is more resilient to climate change and changing ocean conditions.
Maintaining genetic diversity within and among populations is vital to ensure species are resilient to challenging conditions. Without it, a single disease or set of conditions—such as a prolonged change in ocean acidification—could drive a species to extinction.
Fortunately, new research has revealed more genetic diversity across Alaska’s red king crab populations than originally documented. This suggests that the species will be more resilient in the face of changing conditions like ocean warming. However, any efforts to enhance red king crab populations need to be careful not to affect this genetic diversity.
King crab in Alaska
Historically, the red king crab fishery was Alaska’s top shellfish fishery. It’s embedded in the culture of Alaska’s working waterfronts and king crabs have been the centerpiece of holiday feasts around the world. However, the red king crab fishery collapsed in the 1980s. Since 1983, most populations have been depressed statewide and the Gulf of Alaska fishery remains closed.
Wes Larson is co-author of the research published in Evolutionary Applications and the genetics program manager at the NOAA Alaska Fisheries Science Center. He reflects, “When it comes to understanding crab biomass declines and how to recover populations, we need to better understand population structure and local adaptation. There are a lot of concerned and invested fishermen, processors, and community members getting more engaged in these issues and it’s propelling new and innovative research.”
To dig into this need, Larson and a team of collaborators embarked on a study to generate whole genome sequencing data on red king crab in different locations across Alaska. The benefit of whole genome sequencing over previous methods is that it’s akin to reading the full story of an organism’s makeup instead of just a chapter or two. This holistic approach offers more robust analysis in order to tease apart similarities and differences between locations.
New genetics research in Alaska
Traditionally, information about commercially important species comes from fisheries-dependent data (collected on commercial fishing vessels) or independent surveys (from scientific research vessels). From these, we gather data on abundance, size, sex, reproductive status, diet, etc.
Genetics tools help to fill in the information gaps from traditional surveys, and can be used to:
- Define stock of origin
- Assess local adaptation
- Document genetic diversity and inbreeding
Whole genome sequencing builds on past methods by enhancing our ability to detect important differences between populations at finer scales.
Red king crab live in diverse environments—from coastal bays in the north, to open sea shelves in the Bering Sea. They also live in small bays and fjords fed by glacial melt in Southeast Alaska and the Gulf of Alaska. King crab in Alaska generally inhabit the following five regions:
- Southeast Alaska
- Gulf of Alaska
- Aleutian Islands
- Eastern Bering Sea
- Norton Sound / Chukchi Sea.
Previous genetic studies have hypothesized that king crab from these regions are split into three genetic groups:
- Southeast Alaska
- Gulf of Alaska / East Bering Sea
- Aleutian Islands / Norton Sound.
However, these studies used older genetic techniques, which may not provide the resolution necessary to accurately define genetic structure. The current study reinvestigated the genetic structure of the red king crab in all five regions using high-resolution data derived from whole genome sequencing.
The results of this study were revealing and informative. Scientists found substantial genetic structure within populations and genetic diversity between regions. In some cases, scientists observed this diversity between populations separated by only a few hundred kilometers.
“Crabs have pelagic larvae, so this is very surprising given the potential for ocean currents to distribute these larvae long distances,” said Larson. “However, these populations do not seem to be mixing and have become genetically isolated.”
Ultimately, the previous hypothesis of three genetic groupings was revised by this whole genome sequencing study. This updated method provided more clarity of fine-scale genetic differences than previous methods. The data indicate that there are six, possibly seven, genetically distinct populations:
- Southeast Alaska
- Gulf of Alaska
- Aleutian Islands
- Bristol Bay
- Pribilof Islands
- Norton Sound / Chukchi Sea
Data showed previously unrecognized differences between the Gulf of Alaska and East Bering Sea regions. And the East Bering Sea region is split into separate Bristol Bay and Pribilof Islands populations.
Researchers also found that the Aleutian Islands and Norton Sound/Chukchi Sea regions are unique. Data suggests that Norton Sound and Chukchi Sea may be distinct as well. However, further research is required to determine if this is the case.
Scientists attribute this genetic diversity to a combination of factors including populations deriving from different glacial refugia. These are areas that remained ice-free during the lce Age. And more recently, natural selection (genetic changes driven by adaptation) and genetic drift (genetic changes that are random) likely contributed to this diversity. The research documented evidence of local adaptation in most populations.
Fisheries management implications
The scientists’ approach to sequence the whole genome of red king crabs was a more detailed method using orders of magnitude more data than previous studies.
It also confirmed that fisheries are being managed effectively by region in Alaska. For example, crab stocks in the Gulf of Alaska, Aleutian Islands, Bristol Bay, and Pribilofs Islands regions are each managed separately. Prior to this new research, the Bristol Bay and Pribilof Islands were not found to be genetically distinct. This new understanding reinforces that we should continue to manage them separately.
Understanding population structure, and these newly discovered genetic signals of local adaptation, is also important for preventing overfishing on genetically unique populations. And it’s critical to provide information on how local adaptations influence responses to different climatic conditions.
We may find that some populations have the potential to fare better in future climate conditions that are likely as climate change progresses. Genetics can also reveal shifts in population distribution. Some shifts may already be underway in the Bering Sea as the North Pacific warms.
Finally, with the Gulf of Alaska population being depressed, scientists would expect a higher potential for inbreeding and lower genetic diversity. However, researchers found no evidence of reduced diversity, meaning genetic health did not suffer as the population declined. This foundation of genetic diversity means that genetic factors should not limit recovery.
This research also provides important data that can be used to inform broodstock selection for red king crab enhancement programs. Enhancement programs raise young crabs in hatcheries and release them into the wild to enhance the population.
Given the genetic diversity of red king crab across Alaska, it’s vital to prioritize local broodstock for enhancement before sourcing from elsewhere. This helps to keep genetic diversity intact and ensures that the genetic integrity of locally adapted populations is not jeopardized.
More information:
Carl A. St. John et al, Whole Genome Sequencing Reveals Substantial Genetic Structure and Evidence of Local Adaptation in Alaskan Red King Crab, Evolutionary Applications (2024). DOI: 10.1111/eva.70049
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Genetic diversity in Alaska’s red king crab may provide climate change resilience (2025, January 13)
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Alaska
Avalanche closes Alaska Panhandle highway, the latest debris slide after storms deliver historic rain and snow
City Manager for Juneau, Alaska, Katie Koester, joins FOX Weather to talk about how locals are handling the recent flood and avalanche threat and how emergency crews are prepared to handle impending situations.
HAINES, Alaska – An avalanche closed part of a highway in the borough of Haines, a small town about 90 miles north of Juneau in Alaska’s panhandle on Tuesday night — the latest debris slide in the region after days of heavy rain triggered avalanches in Juneau last week.
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Barricades have been placed at Mile 10 of the Haines Highway and crews will begin to assess the damage during the daytime on Wednesday, Alaska Department of Transportation officials said.
(Alaska Department of Transportation/Facebook / FOX Weather)
Earlier Tuesday, the department released a few photos of the highway’s condition and issued a travel advisory before the avalanche and reported that rain-on-ice conditions were making road conditions very difficult.
RECORD SNOW BURIES JUNEAU SCHOOL AND PROMPTS FIVE-DAY CLEANUP
Drivers were urged to stay off the road.
Relentless rain from an atmospheric river has pounded the southeastern part of the state, which has begun to melt a historic amount of snow that fell across the region over the holidays, triggering days of avalanche warnings.
More than 7 feet of snow has fallen across the Alaska panhandle, with the bulk coming after Christmas Eve.
Evacuations were issued in Juneau last week after several large avalanches were reported on the Thane and Mount Juneau avalanche paths Friday.
Governor Mike Dunleavy issued a disaster declaration on Saturday for both the ongoing storms and the record-shattering snow.
Another day of heavy rain is expected, but the precipitation will finally begin to decrease later Wednesday.
Check back for more details on this developing story.
Alaska
Simple handwashing stations improved health indicators in parts of rural Alaska
A key step to preventing the spread of diseases like COVID-19 or influenza is simple: washing hands. But lack of piped water in parts of rural Alaska has made that simple practice not so easy to carry out.
Now a technological innovation has boosted rural Alaskans’ ability to do that important disease-fighting task.
The Miniature Portable Alternative Sanitation System, or Mini-PASS, a portable water station that does not require connection to any piped water system, proved effective at helping people wash their hands properly, and there are signs that its use is fending off contagious diseases among children, according to a recently published study.
The Mini-PASS is a stripped-down version of the full Portable Alternative Sanitation System that was also designed by Alaska Native Tribal Health Consortium and its partners.
The full PASS units typically store 50 to 100 gallons of water, and the units include connections to septic tanks, allowing for flush toilets to take the place of “honey buckets,” the plastic-bag-lined buckets commonly used in rural Alaska areas lacking water and sewer systems. The Mini-PASS units lack those septic connections, and they typically allow for storage of 20 gallons of water. Storage tanks are placed above sinks, and used water drains into collection buckets.
The Mini-PASS units are much cheaper than full PASS systems, costing a little over $10,000 for construction and delivery, according to ANTHC. A full PASS system can cost about $50,000 per household, according to ANTHC. That sum is vastly lower than the cost of extending piped water and sanitation service, which can total $400,000 or more per household in parts of rural Alaska.
Simplicity had its virtues during the COVID-19 pandemic. At the time, there was urgency for distributing Mini-PASS units to several rural communities — places where people living in unpiped homes were hauling water, often in difficult circumstances, then using and reusing it in germ-spreading basins.
The consortium, with the help of partners, distributed hundreds of Mini-PASS units to rural households during the height of the COVID-19 pandemic. At least 350 units had been distributed as of 2021, and more have gone out since then.
“The idea was people were not going to be reusing the water, that it was free flowing, that you’d wash your hands, and then it would go into the wastewater bucket, the gray water bucket,” said Laura Eichelberger, an ANTHC research consultant and co-author of the study.
“And because the pandemic was this urgent situation of crisis, they needed to get as many of these units in as they possibly could. And so they took the idea of the PASS and just made it as simple and cheap as possible,” she said.
The recent study used interviews to measure the effectiveness of mini-PASS. In all, there were 163 interviews from 52 households.
Water use is considered an indicator of public health, and the Mini-PASS units led to an increase in water use that expanded over time, the results found. Average water use per person increased by 0.08 gallons per month in households that used the units, meaning that after a year, water use was up by 0.96 gallons a day per person, or 3.6 liters per day, the results found.
Additionally, people with Mini-PASS units reported that children 12 and under had fewer symptoms of contagious diseases.
There was a “statistically significant decrease in the reported symptoms, respiratory in particular, for households who were actively using the Mini-PASS as their primary hand- washing method, compared to those that were still using wash basins,” said Amanda Hansen, the study’s lead author and another ANTHC health researcher.
Prior to the distribution of Mini-PASS units, water use in unpiped villages in Alaska averaged only 5.7 liters per person per day, according to a 2021 study by researchers at Canada’s McGill University. That was well below the World Health Organization standard of 20 liters per person per day, according to that study.
Parts of rural Alaska continue to face daunting challenges in securing adequate water and sanitation services. According to the Alaska Department of Environmental Conservation, more than 30 communities were considered “unserved” as of 2020. The category applied when less than 55% of homes are served by piped, septic and well or covered haul systems.
Still, there has been significant progress in recent years. According to the Environmental Protection Agency, the number of rural Alaska homes without water, sewer or both has decreased by a notable 70% over the past two decades.
Originally published by the Alaska Beacon, an independent, nonpartisan news organization that covers Alaska state government.
Alaska
Mary Peltola may put Alaska’s Senate race in reach for Democrats
This story was originally published by The 19th.
This story was originally reported by Grace Panetta of The 19th. Meet Grace and read more of their reporting on gender, politics and policy.
Former Rep. Mary Peltola is challenging GOP Sen. Dan Sullivan in Alaska, potentially putting a tough race in reach for Democrats.
Peltola, a Democrat who served one term as Alaska’s at-large U.S. House representative from 2022 to 2025, was widely seen as a prized top recruit for the race and for national Democrats, who have an uphill battle to reclaim control of the U.S. Senate in 2026.
Peltola, the first Alaska Native person elected to Congress, focused on supporting Alaska’s fisheries while in office.
“My agenda for Alaska will always be fish, family and freedom,” Peltola said in her announcement video Monday. “But our future also depends on fixing the rigged system in D.C. that’s shutting down Alaska while politicians feather their own nest.”
“It’s about time Alaskans teach the rest of the country what Alaska first and really, America first, looks like,” she added.
A 2025 survey by progressive pollster Data for Progress, which regularly polls Alaska voters, found that Peltola has the highest approval rating of any elected official in the state. She narrowly lost reelection to Republican Rep. Nick Begich in 2024.
Elections in Alaska are conducted with top-four nonpartisan primaries and ranked-choice general elections. In the Data for Progress poll, 46 percent of voters said they would rank Sullivan first and 45 percent said they would rank Peltola first in a matchup for U.S. Senate. Sullivan won reelection by a margin of 13 points in 2020.
Republicans control the Senate by a three-seat majority, 53 to 47, and senators serve six-year terms, meaning a third of the Senate is up every election cycle. For Democrats to win back the chamber in 2026, they’d need to hold competitive seats in states like Georgia and Michigan while flipping four GOP-held seats in Maine, North Carolina and even more Republican-leaning states like Alaska, Ohio, Iowa, Nebraska and Texas.
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