The Wyoming Game and Fish Department has 10 hatcheries and rearing stations producing eggs and raising fish to stock a variety of fish, mostly trout. In order to meet the stocking requests from our fisheries biologists, hatcheries and rearing stations work together to produce different varieties and sizes of trout for your favorite waters. As stocking deadlines approach, hatchery and rearing station staff can either speed up or slow down fish growth by varying water temperatures and feedings to ensure the trout grow to just the right size.

Moving fish between different water temperature can manipulate their growth rate. Colder water slows down fish growth while warmer waters speeds it up. Feeding rates are also important for fish growth. Combined with water temperature, more food can boost growth rates quickly. As water temperature increases so does metabolism and the rate at which the fish can convert food to flesh.

Fish culturists manipulate growth when they want to grow two different sets of trout at the same rate. Eggs or fry might come from two different hatcheries to be raised in a rearing station, with one lot larger than the other. These fish can be raised to be the same size, at the same time, by keeping them in different water temperatures. Fish typically are raised to be stocked at 3-4 inches long. In urban fisheries and some waters with predacious fish like walleye or lake trout, other trout species may be as big as 8-10 inches when stocked.


Bart Burningham
Ten Sleep Hatchery Superintendent


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