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Tillett Springs Rearing Station
Tillett Springs Rearing Station
P.O. Box 416, 195 County Road 16
Tillett, Wyoming 82431
(307) 548-6650
2.5 miles east of Lovell on U.S. Highway 14A, then 10 miles northwest on State Highway 37. Continue 4 miles on Crooked Creek Road.
Located on the western slope of the Big Horn Mountains, Tillett Springs Rearing Station is approximately 17 miles northeast of Lovell, Wyoming. The rearing station was constructed in 1958 and named for the Tillett Ranch. The ranch owners granted a 99-year lease for $1.00 to the Wyoming Game and Fish Department for the property. Located a short distance from Pryor Mountain Wild Horse Range and Bighorn Canyon National Recreation Area, this facility offers visitors scenic beauty as well as the opportunity to view fish culture activities.
The main focus of the rearing station is the care and maintenance of the Firehole rainbow broodstock, but other species raised include brown trout, Eagle Lake rainbow trout, and both the Yellowstone and Snake River cutthroat trout.
Where does Tillett Springs get its water?
Two natural springs provide an excellent source of water supplying 1,380 gallons of water per minute at a constant temperature of 54 F. Tillett Springs Rearing Station has one concrete pond, two dirt ponds, and 12 concrete raceways 5 feet wide and 100 feet long to raise fish. Fish are grown to stocking size in the concrete raceways and one of the dirt ponds. The concrete pond and second dirt pond are used to house the Firehole rainbow broodstock.
The Firehole rainbow broodstock held at the station consists of approximately 3,100 fish weighing on average two to three pounds. The broodstock fish usually become sexually mature in their third year. This broodstock came from the Firehole River in Yellowstone National Park.
How does Tillett Springs spawn?
Spawning at the station usually begins in November and continues through January with the broodstock annually producing about 1.5 million eggs. When fish are preparing to spawn they will travel upstream in search of suitable habitat. Personnel take advantage of this natural movement to capture spawning fish by placing a funnel shaped trap in the concrete raceways. After fish are captured they are separated by sex and held until spawned.
Eggs are collected in bowls by gently squeezing the abdomens of a female, with the average rainbow producing 1,400 eggs. The eggs are then fertilized with the sperm or "milt" from a male. Fish are spawned at a 1:1 ratio to provide the best genetic diversity. Fertilized eggs are then placed in large coolers and shipped to other facilities for hatching. Tillett is a rearing station and does not have the equipment to hatch the fertilized eggs. After spawning, the fish are released unharmed to spawn again next year.
Fertilized eggs are placed in incubators for 20-30 days. When the eggs begin hatching, the fish are then placed in small troughs where they begin growing. Small fish are fed frequently, often as many as eight times a day.
How does Tillett Springs stock fish?
Once fish have reached the size requested by fish management crews they are ready to be stocked. The Wyoming Game and Fish Department only stocks fish in waters where there is suitable habitat and public fishing is allowed. Around 200,000 fish are stocked from this facility each year.
There are several ways fish are stocked. Trucks, barges, and even helicopters help the fish reach their final destination. Trucks are the most common way of transporting fish from the facility to a lake or river. Insulated tanks keep the water cool while oxygen bottles and aerators provide oxygen to the fish during transport. Barges with onboard tanks are used when fish need to be stocked in a particular part of a river or lake. Helicopters are used when a lake is inaccessible by truck, such as in high mountain lakes in wilderness areas.
The Tillett Springs Rearing Station serves the Wyoming public as well as other states by providing high quality fish for anglers. This insures angling opportunities for the present and future generations.
In 1994, an isolation hatchery was constructed at Tillett to give the station the ability to raise fish of undetermined disease status. The primary function of the isolation hatchery is to hatch eggs collected from a wild brood source. The eggs and fish are kept isolated from all other fish on the station until they pass disease inspection. After passing the inspection the fish can then be transferred to other rearing units on the station, or to other hatcheries in the state to be reared for stocking. Currently the isolation hatchery is being used to hatch Yellowstone cutthroat eggs taken from Le Hardy Rapids in Yellowstone National Park.