ASK GAME AND FISH Q: Why do fish hatcheries and rearing stations manipulate trout growth and how do they do it? A: The Wyoming Game and Fish Department has 10 hatcheries and rearing stations that produce eggs and raise fish to stock. Most of those fish are trout. In order to meet the stocking requests from fisheries biologists, hatcheries and rearing stations work together to produce different varieties and sizes of trout. 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. Bart Burningham, superintendent of the Ten Sleep Hatchery, said moving fish between different water temperatures can manipulate their growth rate. Colder water slows down fish growth while warmer waters speeds it up. Burningham said feeding rates also are important for fish growth. Combined with water temperature, more food can boost growth rates quickly. FOR MORE INFORMATION ABOUT GAME AND FISH'S HATCHERIES AND REARING STATIONS, GO TO: HTTPS://WGFD.WYO.GOV/FISHING-AND-BOATING/ FISH-HATCHERY-INFORMATION. " As water temperature increases so does metabolism and the rate at which the fish can convert food to flesh, " Burningham said. 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 much 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. Burningham said fish typically are raised to be stocked at 3 to 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 to 10 inches when stocked. - WGFD staff WYOMING STYLE Check out our newest Wyoming-themed t-shirts at the Game and Fish Store. WYOMING GAME AND FISH DEPT. ONLINE STORE SHOP ONLINE at wgfd.wyo.gov/store or call 1-800 LIV-WILD 12 | August 2021HTTPS://WGFD.WYO.GOV/FISHING-AND-BOATING/ http://wgfd.wyo.gov/store