Watch Utah Wildlife Officials Airdrop Thousands of Fish into a Lake

For these fish, the fastest way to the water is down.

Wildlife officials in Utah have been stocking their remote mountain lakes by dropping fish from airplanes since 1956. And on Aug. 21, the Utah Division of Wildlife Resources (DWR) shared a video of them doing just that. In the video, the small fish erupt from the bottom of an airplane in a billowing jet of water.

It might seem like the fall from the plane would result in a violent, fatal end for the fish, but the Utah DWR explained in a tweet that at least 95 percent of the fish are expected to survive. That's because the young fish are so small — only 1 to 3 inches (2.5 to 7.6 centimeters) long — that they fall to the water like leaves, said Phil Tuttle, the outreach manager for the southern region office of the Utah DWR. [In Living Color: A Gallery of Stunning Lakes]

The pilot flies just above the tree line to drop the fish, or as low as possible while considering other natural barriers like cliffs and mountains, Tuttle told Live Science in an email. Years of netting surveys (collecting fish in a net and counting them) and decades of successful recreational fishing suggest the fish do all right after their aerial plunge. Utah DWR staff members have also conducted netting surveys within minutes of a drop to verify initial survival rates. 

More than 200 of Utah's remote mountain lakes are stocked every year using this aerial fish-drop method. The lakes are often far from any road and can take a long time to reach by land, which makes land transports more stressful for the fish compared with aerial transports.

Most of the stocked lakes would be fishless, were it not for the DWR's stocking efforts. The DWR primarily stocks lakes with sterile fish so they can control the population and minimize their impact on native wildlife species. The most common species to make these flights are various species of trout, a hybrid trout known as splake (Salvelinus fontinalis) and Arctic grayling (Thymallus arcticus).

Original article on Live Science.

Kimberly Hickok
Live Science Contributor

Kimberly has a bachelor's degree in marine biology from Texas A&M University, a master's degree in biology from Southeastern Louisiana University and a graduate certificate in science communication from the University of California, Santa Cruz. She is a former reference editor for Live Science and Her work has appeared in Inside Science, News from Science, the San Jose Mercury and others. Her favorite stories include those about animals and obscurities. A Texas native, Kim now lives in a California redwood forest.