The biennial stocking of wilderness lakes in the Bighorn Mountains took place July 27 and 28 via helicopter with more than 30,000 fish stocked in 26 Sheridan Region lakes. Additional lakes on the west side of the mountains were stocked as well.

Only a small percentage of the many high elevation lakes in the Bighorns are stocked; others have natural reproducing populations and some are fishless. Game and Fish fisheries biologists survey remote, high elevation lakes each summer and develop a stocking schedule based on sampling results and creel survey data returned from anglers.

“Game and Fish has developed a long-term schedule to evaluate populations of Cloud Peak Wilderness and other alpine lakes,” said Sheridan Region Fisheries Supervisor Paul Mavrakis. “Lakes on the east slope of the Bighorns are scheduled for stocking on even years. Some of the lakes are on a two-year rotation while others are on a four-year rotation.”

Stocking fish by helicopter has taken place in Wyoming since the 1970s. It is a safe, efficient way to stock thousands of fish in dozens of lakes in a short amount of time.

The very early days of fish stocking involved carrying fish in metal jugs or canisters on horseback. Later methods included carrying fish in plastic containers via backpack or horseback. These methods occasionally resulted in high mortality of the fish and took substantial investments of time and personnel. Stocking a high elevation lake by helicopter now takes just a few minutes and there is little mortality of fish.

The fish are loaded in eight cylinder shaped tanks, which are attached to the helicopter by a cable. Each tank holds approximately five to eight gallons of iced water and 10 to 25 pounds of fish, depending on the size and species of the fish. Each tank may contain different species or sizes of fish, depending on the lake to be stocked

Each tank compartment has a door that opens at the bottom to release the fish as the helicopter maneuvers over the lake. The pilot has a control switch that can trigger each door individually or all eight tank doors at once. The canisters are approximately ten feet above the water when they are opened.

The stocked fish are fingerlings ranging from one to six inches in size. This year, splake, tiger, rainbow and Yellowstone cutthroat trout from the Daniel and Tensleep hatcheries and the Wigwam Rearing Station were stocked.

Fish grow slowly in the cold temperatures of alpine lakes, but the recently stocked fish will eventually reach mature lengths of 12 to 14 inches. Anglers can learn more about the diverse fishing opportunities in Cloud Peak Wilderness and other areas of the Bighorns by visiting the new statewide interactive fishing guide.