| When stocked by airplane, fish can drop from 50 to 150 feet and land safely in the water below |
For those who have wondered how fish make their way into backcountry lakes that are inaccessible by vehicle in Utah, the answer is by airplane.
Historically, fish made their way into the backcountry on horses. They were delivered from a Utah fish hatchery by truck to a crew of men and a pack train of horses. Fish and water were off-loaded into metal milk cans, which were tied to the sides of the horses. Gunnysack material was used to cover the opening, to prevent the fish from jostling out. The crew would then begin the long journey through the drainage, planting the steams and lakes as they went.
Some trips would last seven or more days, and it took an entire summer to stock all the lakes.
As the horses walked, the water in the milk cans would jostle, providing enough oxygen to keep the fish alive. Utah Fish and Game Department personnel would also use the water from the stream or lake they were stocking to replace the water lost from the milk cans.
In 1956, the agency changed the backcountry-stocking program to a more modern method: stocking by airplane.
Four of the Division of Wildlife Resources’ 12 state fish hatcheries are involved in aerial stocking. The Kamas, Fountain Green and Whiterocks hatcheries do their aerial stocking in July, while the Glenwood hatchery completes its aerial stocking in September.
Here’s how it works:
•At 4 a.m. on a July morning, employees begin work by prepping the fish trucks and filling them with water. There is rational behind why the work begins so early in the morning. When flying in a small airplane at low elevations, calmer air lends to safer flights. As the sun rises the earth surface’s begins to warm, causing the air to move, or, in other words, wind. This creates up drafts and/or down drafts that blow the airplane around, especially when it’s flying next to and around high mountain peaks. These drafts make it unsafe to fly.
•Six fish species are stocked by airplane: rainbow trout, cutthroat trout, brook trout, tiger trout, splake and Artic grayling. These fish are between one to three inches in length when stocked using an airplane. This small size is to ensure the fish will survive the drop from the plane.
•Thousands of a single fish species are carefully loaded into a water tank on the back of a stocking truck. A second hatchery truck is also filled with water that will be used to fill the water tank in the plane. Now the drive is on to the nearest airport to meet the incoming airplane.
•The DWR has two pilots who fly two Cessna four passenger airplanes owned by the division. The planes are fixed wing, 185 horsepower, tail dragger aircraft that are very maneuverable at low elevations.
The back seats in the planes have been replaced with a seven compartment metal tank. Each compartment has an air stone attached to the inside bottom with individual oxygen supply lines. Oxygen gas is supplied from a small compressed oxygen bottle strapped to the outside of the tank.
•Approximately one gallon of water from the fish truck is pumped into each of the seven compartments. Water adds weight to the airplane, so careful consideration of the combined weight of water and fish must be taken into account.
•Fish are then caught by a dip net from the fish truck tank and weighed out to the nearest tenth of a pound. The number of fish per pound corresponds to the number of fish required by a stocking quota DWR biologists have set for each lake. Each of the seven tanks is then loaded with as few as two pounds or as many as 50 pounds of fish (equaling about 200 to 7,000 fish).
•Once the fish and flight crew are loaded, the plane flies to the destination drainage and corresponding lakes. Hatchery personnel assist the pilot in locating the correct lake using their experience and Global Positioning Systems (GPS).
Once he’s over the desired lake, the pilot evaluates his approach and exit, plane speed, windage and altitude, and lines up with the lake. While over the lake, he triggers one or more of the toggle switches on the plane’s instrument panel. This opens the compartments, allowing the water and fish to drop into the lake below. The fish fall between 50 to 150 feet, depending on how close to the lake the pilot can fly.
Because of their small size, this process of dropping doesn’t hurt the fish (it’s like a high diver diving into a deep pool of water). The survival rate of these fish is around 99 percent.
This means up to seven lakes can be stocked in one flight and that 40 to 60 lakes can be stocked in one day. The entire state of Utah can be stocked in about 10 days, compared to an entire summer by horseback.
Once all the lakes that can be stocked for a single flight are completed and the tanks are completely empty, the plane returns to the airport to be reloaded with water and fish for another flight.
On a good morning, using both airplanes, seven to 10 fights can be made to stock the lakes in the Uinta Mountains. Stocking the backcountry lakes in the Uintas may occur once a year, while other lakes within the Uintas are stocked every second, third or even fourth year. The rotation depends on the individual lake.
The Wasatch Mountains, Uinta Mountains, Manti Mountains, Fish Lake lakes, Boulder Mountains, La Sal Mountains and Cedar Mountain are the areas in Utah that are stocked by airplane. So, next time a low-flying airplane is visible over these mountains in July, know that the pilot is probably carrying some fish with him.