Description: Greenback cutthroat trout are coldwater fish belonging to the trout, salmon and whitefish family. They have dark, round spots on the sides and tail and two colorful blood-red stripes on each side of the throat under the jaw, hence the name "cutthroat." During the spring spawning season the entire belly may become crimson red. The greenback was named Colorado's state fish in 1994.
Range: Greenbacks originally lived in the mountain and foothill areas of the Arkansas and South Platte river systems in Colorado and part of Wyoming. Today, they exist in only about 5 percent of their original range.
Habitat: Greenbacks prefer cold, clear, gravely headwater streams and mountain lakes which provide an abundant food supply of insects.
Diet: Greenbacks feed on crustaceans such as fresh-water shrimp, aquatic and terrestrial insects, and small fish.
Reproduction: Spawning occurs usually from late May to mid-July in higher elevations. Male cutthroat spawn first at age two, and females mature a year later. Females build an egg pit in gravel generally three to eight inches deep and one foot in diameter. A 10-inch female will lay about 800 eggs. Larger fish of about four to seven pounds will lay up to 6,000 eggs.
Endangered Status: The greenback cutthroat trout is listed as threatened both federally and in Colorado. Their numbers began to decline due to over-fishing, stocking of rainbow, brook, brown and Yellowstone cutthroat trout in their habitat, and loss of high-quality trout stream habitat due to logging, livestock over-grazing, water diversions and municipal and industrial pollution.
A cooperative recovery effort between the Division of Wildlife, U.S. Forest Service, Bureau of Land Management, U.S. Fish and Wildlife Service and Rocky Mountain National Park was initiated for the greenback cutthroat trout. This recovery team, and university researchers and interested conservation groups such as Trout Unlimited, continue to conduct systematic searches for existing populations and suitable reintroduction sites.
The team also has initiated stream improvement projects and a hatchery-based restoration stocking program. Adult and juvenile greenbacks have been stocked into alpine and montane lakes and streams in the South Platte and Arkansas River basins since the late 1960s. Many of the historic and restored populations are located in Rocky Mountain National Park. Presently, greenback trout occur in 58 lakes and streams and 23 of these meet the population criteria required by recovery goals.