Hatching a plan — Fishery lab zip up population, conservation problems
The University of Idaho College of Natural Resources hosted Shawn Narum, lead conservation geneticist with the Columbia River Inter-Tribal Fish Commission, for a lecture on hatchery research and methodology Monday night.
Narum said there are concerns that particular populations of fish will disappear in the Columbia River basin. He works at a laboratory in Hagerman, Idaho, with a team of more than a dozen fellow researchers to find solutions.
Narum said his team tracks genetic origins of fish populations, determines whether fish are being harvested by fishermen or at hatcheries, investigates behavior between wild and hatchery fish and explores the genetic bases for adaptations to the environment and other influences.
Populations decrease over time, he said, because of habitat destruction due to deforestation and the influences of mining, pollution and dams. He said studies show a subtler problem — hatchery fish can hinder the viability of future spawn when they mate. If a hatchery group grows up without proper influence from natural conditions, individuals less capable of surviving in the wild will thrive and spread their incapacity among successive wild populations upon release from the hatchery.
Narum said his team is researching ways to prevent this genetic tendency.
While hatcheries can help increase numbers, Narum said the central concern is how to improve hatchery rearing methods and other conservation techniques to better boost critical populations.
His team advocates the use of such positive rearing practices as using only local fish stock for supplementation hatcheries as well as limiting the “recycling” of hatchery fish through successive generations, which can accumulate negative genetic problems. Another method is rearing fish in a similar timeframe as those raised in the wild, he said.
“That’s the goal — to have these hatchery supplementation programs that rear the hatchery fish as closely as possible to their wild counterparts, so that they don’t negatively impact wild populations,” Narum said.
His team also conducts research in adaptation in order to better understand how fish react and survive amid changing climates and various diseases. He said the results will inform the team’s conservation focus.
Though the research is limited to fish in the Pacific Northwest, Narum said many wildlife populations around the world can benefit from tracking and reproductive cultivation.
“(Issues) like climate change have effects on most species that will either need to move, adapt or die,” Narum said. “The genetic approaches we are taking to address these issues can be applied to many other species with similar conservation concerns.”
Matt Maw can be reached at email@example.com