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Staff at Erwin National Fish Hatchery are hard at work, kicking off the 2025-2026 spawning season. Erwin National Fish Hatchery is a part of the USFWS National Broodstock Program, and staff work hard to produce millions of certified disease-free Rainbow and Brook Trout eggs. These eggs are sent to federal, state, and tribal hatcheries, where they are grown-out and stocked to provide fish for recreation and mitigation.
The spawning season kicks off in July every year, when the Erwin Arlee Domestic (EAD) strain of Rainbow Trout are ready to spawn. During the first week of spawning, staff will carefully sort the trout by sex. This is a long process, especially since there are almost 7000 spawning age EAD Rainbow Trout at the hatchery. During the sorting process, the fish are crowded in the center of the raceway, and are netted into tubs containing a sedative. This sedative briefly blocks oxygen uptake for the fish, rendering them temporarily unconscious. This makes the process less stressful for the fish and allows staff to carefully inspect the fish to see if they are male or female, and to see if the females are ripe. Ripe females are ones that are ready to lay their eggs. Unripe females are placed in the upper portion of the raceway, ready to be checked again in upcoming weeks. Males are placed at the bottom of the raceways, and the ripe females are placed in the middle of the raceways for spawning.
The next day the trout are ready to be spawned. A table is placed in the raceway, between the males and the ripe females. On the tables are all of the necessary materials for spawning, including bowls, saline, iodine, five-gallon buckets, nets, and a notebook. The males and females are once again netted into the tubs with a sedative. Saline is poured into the spawning bowls, and eggs from the females and milt from the males are stripped from the fish into the bowls. Then, the eggs are rinsed in water before being placed in an iodine solution to reduce the risk of disease. This process is repeated until all of the females have been stripped of eggs. Once spawning is complete, the eggs are brought up to the main hatchery building, where they are incubated for two weeks before they are shipped out to other hatcheries for grow-out, and 12-18 months later they can be stocked for anglers to catch!
