Story Hatchery personnel will be busy with brook, brown and lake trout spawning through the month of October.
Every Monday, personnel inspect females to identify individuals whose bellies are swollen with eggs and ready to spawn. These individuals are moved to separate raceways and spawning is done later in the week.
During each day’s spawning, eggs from females and sperm, or milt, from males is collected and combined in small bowls which are then covered with freshwater to activate fertilization. The bowl of fertilized eggs is then repeatedly rinsed with clean water and bad eggs and impurities are removed. Once cleaned, the eggs are placed in coolers for transport to incubators.
Males and females from different age classes are used for spawning to maintain genetic diversity and prevent accidental breeding of related fish.
A tablespoon of fertilized eggs from multiple pairings is set aside in a small cooler each day. This special group of eggs will be incubated and raised separately from the other collected eggs to become the hatchery’s future brood stock. Taking eggs from a variety of pairings ensures maximum genetic diversity.
For this fall’s spawning, personnel will use 590 lake trout, 1,690 brook trout and 2,800 brown trout. Each female brook and brown trout will produce approximately 1,500 eggs while a lake trout female can produce up to 4,500 eggs.
All of the fertilized eggs collected during the spawn will spend several weeks in incubators at the hatchery with water temperature carefully monitored. When their eyes begin to develop, they are packaged and shipped to several other hatcheries and rearing stations in the state to continue their development. Some of the eggs will leave Wyoming and head to hatcheries and rearing stations in Idaho, Colorado, Oregon, California, Utah and Arkansas.
The majority of fish will be stocked in Wyoming waters when they reach a releasable size, but the batch of young future brood stock fish will eventually return to Story to be used for future spawning.