Wyoming's Native Fish Species
Page Summary: Fish species native Wyoming's lakes and streams.
The brown trout was introduced to America from Europe. It is now widely distributed in lakes and streams throughout Wyoming. In streams, brown trout prefer dense cover, particularly overhead cover from undercut banks and vegetation. Brown trout are slightly more tolerant of high water temperatures than other trout. The brown trout is a fall spawner. Like most trout, young browns feed on aquatic insects, crustaceans, and plankton in lakes and reservoirs. Brown trout over twelve inches usually prefer larger food items such as small fish and crayfish. Due to their longer life span (up to ten years) and preference for large food items, brown trout often reach trophy sizes. Fish over ten pounds are not uncommon, and fish over twenty pounds have been taken from the North Platte River and Flaming Gorge Reservoir. The current state record from Flaming Gorge is 25.81 pounds, though fish over thirty pounds have been taken by anglers on the Utah end of the reservoir. Brown trout are more nocturnal than other trout and, therefore, early morning and late evening fishermen are usually most successful. Most conventional trout fishing techniques work for brown trout. Trolling large plugs is especially effective for trophy browns in large reservoirs. Browns are distinguished from rainbow and cutthroat by the relative lack of spots on the unformed caudal fin, by the typical presence of orange spots on the side, and by the orange border on the adipose fin. Brown have dark spots on a lighter background versus light spots on a darker background as found in brook trout. A hybrid between the brown trout and brook trout, called the tiger trout, is sometimes seen in Wyoming, characterized by a rather striking striped color pattern.
Rainbow trout are native to the Pacific coast and have been introduced widely to Wyoming. Rainbow are presently the most important fish used in Wyomingís hatchery system. The rainbow, like the cutthroat, is a spring spawner. Since these two species are fairly close relatives, hybridization often occurs. Because of this, rainbow are no longer being stocked in waters containing native populations of cutthroat trout. Rainbow prefer cool, clear water, either streams or lakes, with maximum water temperatures below seventy degrees Fahrenheit. Food of the rainbow trout in lakes is mainly plankton, but they also eat aquatic insects, snails, crayfish, and fresh water shrimp. Larger rainbow prey on small fish. The primary food in streams is aquatic insects. Rainbow are readily caught with spinning, bait, and fly fishing gear. The current state record for rainbow trout is a twenty-three-pound fish taken from Burnt Lake in Sublette County. Rainbows are distinguished from cutthroat by the absence of basibranchial teeth, the absence of cutthroat markings under the jaw, a white tip on the pelvic and anal fins, and more uniform spotting pattern. They are distinguished from kokanee by eleven anal fin rays versus thirteen to fifteen for the kokanee.
The brook trout is native to the eastern United States and Canada from Labrador to Georgia and westward to Wisconsin. This species was widely introduced in the western United States from the late 1800s until around 1940. The brook trout prefers clean, cold streams and has become well established in the mountain regions throughout most of the state. The brook trout is a prolific fall spawner. In small streams, it often overpopulates, which may eliminate other trout species and cause the brook trout to remain ìstuntedî or unable to grow past a relatively small size. Like most stream trout, brook troutís food consists mainly of aquatic insects. Larger brook trout, particularly in lakes, often feed on smaller fish. Brook trout are easily caught using most popular fishing methods. The state record fish was taken from Green River Lake and weighed 9.69 pounds. Most brook trout in Wyoming range from six to ten inches. The brook trout is distinguished from the true trout (genus Salmo) by light spots on a dark background, and from lake trout by a relatively square caudal fin and the presence of blue or pink spots.
The Cutthroat trout is the only trout native to Wyoming. Six subspecies of cutthroat originally occurred in Wyoming, through the greenback cutthroat of the South Platte Drainage is now extinct in the state. The subspecies still found in Wyoming include the Colorado River cutthroat from the Green and Little Snake River Drainage, the Yellowstone cutthroat from the Yellowstone Basin, the Bonneville cutthroat from the Bear River Drainage, the West Slope cutthroat from the Upper Missouri Drainage in Yellowstone Park, and the Snake River cutthroat from the Snake River Drainage. Cutthroat are not native in the North Platte Drainage.
The Snake River cutthroat is a fine-spotted variety while the other subspecies have larger spots. Cutthroat are spring spawners. Principal food of the cutthroat is plankton and aquatic insects in lakes, and aquatic insects in streams. Cutthroat over twelve inches, especially Snake River cutthroat, often feed on small fish and crayfish. Most convention trout fishing techniques work fine for the cutthroat ? in fact, they are one of the easiest trout to catch on hook and line. the state record cutthroat weighed fifteen pounds and was taken from Native Lake, Sublette County, in 1959. Cutthroat can be distinguished from other trout by the orange or red ìcutthroatî markings under the lower jaw. They are also distinguished from rainbow trout by the presence of very small basibranchial teeth (toward the back of the tongue) and black spotting or purplish color of the pectoral, pelvic, and anal fins which usually have white tips in rainbow trout.
Fish species description are compliments of the Wyoming Game and Fish Department.