The splake, Salvelinus namaycush X S. fontinalis, is a hybrid sport fish created by crossing a lake trout with a brook trout. In Utah, the splake has been introduced to Fish Lake, Mill Meadow Reservoir, Causey Reservoir, and several other lakes and reservoirs. Because the splake is a hatchery-produced hybrid, is does not occur naturally anywhere in the world.
Like many other hybrid fishes, splake do not spawn. This characteristic allows the Utah Division of Wildlife Resources to control the number of splake in a lake at any one time. Also, because splake put little energy into reproduction (such as energy for egg production, finding a mate, and so on), they grow more quickly than they otherwise would. Splake prefer the cold water of Utah's deeper lakes and reservoirs.