In the fall of 1948, a twin-engine plane flew low over remote Chamberlain Basin in central Idaho and released a series of wooden boxes, each fitted with a parachute and carrying a live beaver, into the wilderness below.
It was not a stunt or an accident. It was an intentional wildlife management experiment devised by Elmo W. Heater of the Idaho Department of Fish and Game, intended to solve a truly awkward logistical problem: how to move dozens of beavers from low-lying, populated areas where they had become a nuisance to a remote, mountainous, roadless region where building a dam would actually help the local habitat. Remarkably, the plan worked, and the story of how it came together and why it made sense at the time remains one of the strangest chapters in the history of American wildlife conservation.
Most of the relocated beavers survived the journey and quickly established new colonies, building dams that created wetlands, slowed the flow of water and improved habitat for fish, birds and other wildlife. The project has since become one of the most famous examples of innovative wildlife relocation in the United States.
Why did Idaho have a beaver problem in the first place?
According to Heater’s own 1950 report on the project, published in the Journal of Wildlife Management, beavers are abundant in parts of Idaho and can cause damage to irrigation systems, orchards and other plantings, a problem that worsened after World War II as more people moved to rural areas around towns like McCall and Payette Lake.
Fish and Game officials had already been trapping and relocating these pesky beavers for years, moving them to more remote habitat where their engineering skills could truly benefit fish and wildlife rather than cause headaches for landowners.
The problem was getting the animals into this remote habitat in the first place, since there are no roads at all in the Chamberlain Basin in central Idaho.
Why was the old method of transportation so unsuccessful?
Before parachutes came into the picture, transporting beavers meant loading them onto horses or mules and transporting them for days over rugged terrain, a method that Heater himself described in candid terms. According to a summary of the peer-reviewed study published by Conservation Evidence, a database maintained to track evidence-based conservation interventions, this previous approach has proven laborious, long-term and expensive, with a high mortality rate among the beavers themselves.
Pack animals become skittish and difficult to handle when loaded with agitated, foul-smelling beavers, and the animals are often unable to eat properly during the grueling multi-day journey, arriving weak, increasingly aggressive, or in some cases simply not surviving the journey at all.
The search for a safer and more effective alternative eventually led to one of the most bizarre wildlife relocation experiments in the history of conservation.
How Hetter arrived at parachutes as an actual solution
Faced with this problem, Hitter turned to a resource that was widely available in the immediate postwar years: surplus military parachutes. He decided that the boxes holding the beaver pairs had to be heavy enough to stimulate the deployment of parachutes immediately upon release, and settled on 7.3-metre-long rayon parachutes from wartime surplus stocks as the most reliable option available. Each box is built in two sections that fit together like a suitcase, is equipped with small ventilation holes, and is rigged so that the impact of the landing, combined with the collapse of the parachute, will automatically open the box and allow the beaver to walk straight into its new surroundings without the need for anyone to intervene.
meet Geronimo the beaver who tested the entire system
Before risking any live animal on an actual mission, Hitter and his team ran repeated test drops using dummy weights, and once they were satisfied with the basic mechanics, they turned to a specific beaver for a final round of live testing. An old male beaver, named Geronimo, was repeatedly shot down in the flying field, with someone on hand each time to retrieve him as soon as he emerged from the box, Heater wrote.
Geronimo is said to have become so accustomed to the process that he eventually stopped resisting and would simply crawl back into his box once approached, ready to send him aloft again, a track record that earned him a place on his first official mission, alongside three female beavers, when the real transport flights finally began.
What happened when the beavers actually flew away?
The first official landing occurred on August 14, 1948, when a twin-engine Beechcraft plane carrying eight boxes of beavers, a pilot and a conservation officer flew over Chamberlain Basin.
According to a summary of conservation evidence for the study, 76 beavers were dropped from the air using parachutes over the course of the project, and all but one survived the landing. The only injury occurred when the box’s securing straps broke mid-flight, allowing the agitated beaver to partially climb out and fall the final stretch to the ground instead of riding the box down safely, a lone mishap in an otherwise smoothly executed operation.
Why do conservationists still cite the experiment today?
Aside from the remaining 75 beavers, the true measure of the project’s success came from what happened after the animals landed. Follow-up observations made about a year later found that the relocated beavers continued to build dams and lodges in their new habitat, evidence that the animals had already settled into the Chamberlain Basin rather than simply surviving falls and wandering off. The project has since become a frequent point of reference in discussions of wildlife transport methods more broadly, and has been cited, along with later techniques such as helicopter transport of animals such as black rhinos and mountain goats, as an early example of finding an unconventional but truly effective way of transporting animals to inaccessible terrain without subjecting them to the prolonged stress of overland travel.