Photo: George Lemmon from Blind Canyon Hatchery performs careful surgery on an adult White Sturgeon in the CSI Hatchery wet lab. During captive spawning, tens of thousands of eggs are collected and fertilized with wild male sturgeon to make baby sturgeon destined for the Snake River.
If you missed Part 3, you can read it here.
Once a sturgeon is settled into the sling, the process to collect eggs can begin. Loose eggs are first collected from the vent with gentle pressure. To get the bulk of the eggs, some minor surgery is needed. Next, a small cut is made into the body cavity. Eggs are carefully spooned out and transferred to a measuring jar. The volume of eggs is recorded to estimate the total number of eggs collected for each fish. Each sturgeon is carefully stitched up after collecting eggs and treated with antibiotics to prevent infection after the surgery.
Photo: After the eggs are collected, the spawning incision is carefully sutured together and disinfected. Spawned sturgeon are then kept in captivity for several months to heal and recover before being released back into the Snake River.
Local sturgeon experts Linda and George Lemmon (from the Idaho Aquaculture Association) are on hand to assist with the sturgeon spawning process. Their involvement has been critical to developing successful captive spawning techniques and has helped maintain indigenous stocks of sturgeon throughout the aquaculture industry in southern Idaho.
After the spawning incision is carefully stitched up and disinfected, spawned sturgeon are returned to the hatchery ponds outside. They will remain at the hatchery for 3-4 months to recover and heal. Once they are fully healed, they will be loaded onto a truck and taken back to the Snake River. Before being released, each sturgeon is individually tagged. Biologists record tag numbers during population surveys to keep track of adults that have been spawned several months or years before.
Photo: CSI hatchery staff return an adult sturgeon to the holding ponds to recover after captive spawning. The orange tag in the dorsal fin is used to identify each fish while in the hatchery. After spawning, wild adult sturgeon will spend several months healing before being released back into the Snake River.