Conserving Snake River Sturgeon: Wild brood stock (Part 2 of 7)

Photo: An adult White Sturgeon comes up from the depths of the Snake River during a population survey.

If you missed the Introduction (Part 1), you can read it here!

The middle Snake River has been changed by dams and water diversion so that river flows and habitat no longer support natural spawning in most reaches. Without reproduction to maintain their populations, these long-lived fish would slowly disappear. Idaho Fish and Game is working with Idaho Power Company and the College of Southern Idaho to boost numbers of young sturgeon. This conservation hatchery program is just one part of a bigger strategy to help preserve White Sturgeon in the middle Snake River. 

Photo: Idaho Power Co. biologist Ken Lepla checks maturity of an adult Snake River White Sturgeon. Adult sturgeon must be carefully examined, since only ripe fish ready to spawn will be transferred into the hatchery.

The first step in the process is to collect wild adult sturgeon from reaches of the Snake River where natural spawning is not occurring. Spawning only wild sturgeon will protect the natural genetic diversity of our local sturgeon populations, which is even more important with fish that can live 50 years or more! 

Photo: Mature sturgeon collected from the Snake River are transferred from boat to truck on their way to being spawned at the College of Southern Idaho to help improve numbers of young sturgeon.

Mature adult sturgeon are collected before the spawning season from February to April, usually from the reach below CJ Strike, where they would otherwise not reproduce. Typically, 2-3 females and 2-3 males are collected each year. Biologists have to make multiple trips to river over several weeks to sample sturgeon until the right fish are found. Each fish is carefully examined to make sure it’s a mature adult. Only “ripe” fish that will spawn in the following months are collected, while the rest are immediately released. If chosen for brood stock, these fish are then transported by boat and tanker truck to the College of Southern Idaho hatchery near Twin Falls. After waiting several months to reach full maturity, these wild adults are then spawned in captivity before being taken back and released into the Snake River.

Fun Fact: North America is home to 8 of the 25 species of sturgeon, but only the White Sturgeon lives in Idaho.

Go to Part 3