Bill Carter was casting a net off of Kotzebue’s sea wall in early June. As sheets of ice floated by, seagulls made sharp dives into the frigid water while bearded seals poked their heads above the surface. They were all hunting for the same thing — the millions of pacific herring on their spring run.
Carter is a fish biologist for the Selawik National Wildlife Refuge. He’s working with researchers from the University of Alaska Fairbanks to map the Pacific herring genome.
Back in Carter’s office, he set up a makeshift lab with a tarp laid out on the carpet. A special freezer hummed in the corner. Carter uses the freezer, which can store samples at extremely low temperatures, to preserve the fish samples until they can be overnighted on dry ice to a lab in Idaho.
The blood samples will be used to test for an anti-freezing compound, which researchers say could be what allows northern populations of herring to survive colder climates as far north as Utqiaġvik.
The Pacific herring is the only known herring species in Alaska — at least, for now. But University of Alaska Fairbanks researchers say herring further north might be a separate species.
“A question that I tend to get alongside this is, do I get to name the species?” said Laura Timm, a research assistant at UAF. “And the answer is no.”
Timms studies genetic differences between Pacific herring from seven spawning locations, from Kotzebue south to Unalaska.
“I think an important piece of context here is that herring are in trouble,” Timms said. “Their numbers are declining. These genomic differences — fingers crossed — could be really important for facing what the future holds.”
Jessica Glass, assistant professor of fisheries at UAF, oversees three separate research projects on pacific herring, including Timm’s.
“We know that the Bering Sea herring are very genetically different from the Gulf of Alaska. Like super, super different,” she said. “We're sort of like, ‘Okay, what's next? What else are the herring going to tell us?’”
Glass said this is where the genetic mapping comes in.
“It’s like a 1000-piece puzzle, and when we get tissue from a fish, we have to break that down, we extract the DNA,” Glass said. “Then we have to sort of break it down into smaller fragments.”
Glass said genetic researchers don’t know how the puzzle pieces connect yet, but they have a vague idea of the final image.
Sydney Almgren, a grad student at UAF, said the science of genomic testing has progressed rapidly in the last few decades.
“We went from having like a handful of genetic markers, like 1000 or 10,000 to now, like whole genome markers… like 3 million, 4 million,” she said.
Almgren’s research is focused on genetic structure, to help determine the sex of herring. Herring are not sexually dimorphic. In layman's terms, that means it's hard to tell by looking if they’re male or female if they’re not actively spawning.
Almgren hopes to create a rapid test for determining a herring’s sex. She said the test could have implications for fish beside herring.
Glass said results from the Kotzebue herring that Bill Carter collected have been mapped. Her research team is interpreting the data but have not set a date to publicly release the results.
