As Alberta anglers dust off their fly rods and gear up for a new season, Dr. Joshua Miller is fishing for information about one of their favourite catches. Since 2014, Arctic graylings have been a species of special concern in Alberta, and sportfishing regulations have required them to be catch-and-release only. But that hasn’t stopped anglers from seeking out the stunning species.
“They are characterized by this really big, beautiful dorsal fin that makes for great photos,” Dr. Miller told the Office of Research Services’ Research Recast(ed) podcast. “And they’re fun to catch on the line.”
The only member of the genus Thymallus in North America (there are 13 species in Europe and Asia), Arctic grayling are part of the family Salmonidae, which includes char, trout and salmon. Dr. Miller’s genetics research examines why this particular species is the only one in North America and how that happened. His work also looks at how we can preserve them.
“In the north, Arctic graylings are part of a subsistence harvest, so it’s important they stick around – not only for anglers but also for people who rely on them as a food source,” he explains.
Previous genetic research revealed two genetic groups of Arctic grayling in North America estimated to have split about three million years ago – one northern and more closely related to fish in Siberia, and one southern that appears to be unique to North America. Both of those genetic lineages occur in Alberta, which means that someone fishing the Freeman River just west of Edmonton could catch a fish more genetically similar to a fish in Russia than the same species of fish in the Hay River near Great Slave Lake.
From a conservation perspective, their populations are managed together, because both genetic groups are part of the same species, explained Dr. Miller.
“Right now, a grayling is a grayling is a grayling. Other than one separate population in Montana, Alberta is the furthest south the species lives, and the environment and climate are very different from here to Whitehorse.”
Dr. Miller said that bringing genetics into the conversation can play a critical part in decision-making when mitigating risks created by environmental changes, like stream temperature and turbidity (levels of particulate matter).
In the summer of 2022, in collaboration with Government of Alberta biologists and community partners from Trout Unlimited, the assistant professor in the Department of Biological Sciences visited six sites around the province – including remote areas near Alberta’s border with the Northwest Territories accessible only by helicopter.
Using photographs and tissue samples from over 200 fish, the research team is putting the finishing touches on a project that looks at whether morphological differences exist between the two genetically divergent groups. Determining whether the two genetic groups of fish look different from one another could signal that they adapted differently and may require different management approaches.
“While it doesn’t seem like a slam dunk, there are statistically significant differences between populations, so they might be on the road to becoming completely different locally adapted fish,” said Dr. Miller.
In the future, he hopes to expand this work into a continent-wide and genome-wide assessment and is currently working on getting tissue samples from the eastern edges of the species range, where they haven’t yet been assessed.
Identifying whether there are, in fact, different species of graylings, along with whether there is migration, inbreeding or a decline in diversity, can impact conservation management.
“If we were planning to move fish from one area to another or trying to re-introduce fish to an area where they’ve gone extinct, we would want to know if a particular lineage is more adapted to a certain environment. Basically, we wouldn’t want to put a species in an area where it won’t survive or thrive.”
He explained that there are currently local management plans for Alberta, but on a federal level, management of this species is one-size-fits-all. This research can help determine whether that approach needs to be more targeted.
And ultimately, the research also impacts those anglers we mentioned earlier.
“Do we have to close a fishery entirely to allow the numbers of fish to increase? Genetics research allows us to monitor if that complete closure affects the abundance of fish and the genetic diversity of those fish in those areas.”