Beavers, planes and parachutes

In 1950, it cost Idaho’s Department of Fish and Game $30 to relocate four beavers via parachute. That included the cost of the boxes to hold the beavers, the parachutes, and flight time, according to a paper published that year in The Journal of Wildlife Management by Idaho Fish and Game Department employee Elmo Heter. The beavers were removed from habitats where they were causing trouble for humans – backing up ponds by building dams, and, in the process, damaging irrigation systems and orchards – and transplanted to places where they would “do much toward improving the habitats of game, fish, and waterfowl and perform important service in watershed conservation.”

Much of Idaho’s wilderness is inaccessible by road, necessitating long journeys on the backs of pack animals for relocated beavers before the plane-and-parachute method was developed. The new method was not only faster and easier for Fish and Game personnel (and, no doubt, the pack animals); it was also safer and less stressful for the beavers, which spent less time in transit and survived the subsequent relocations at a much higher rate.

Heter calls out one beaver in particular who made a direct contribution to the research. “Satisfactory experiments with dummy weights having been completed,” he writes, “one old male beaver, whom we fondly named ‘Geronimo,’ was dropped again and again on the flying field. Each time he scrambled out of the box, someone was on hand to pick him up. Poor fellow! He finally became resigned, and as soon as we approached him, would crawl back into his box ready to go aloft again.” In repayment for his services, Geronimo was released into the wilderness and reportedly established a successful beaver colony.

Beavers are still being transplanted today, and still for the same parallel reasons as in the past – to remove them from places where humans find them a nuisance, and to place them in areas where scientists and managers hope they can do some good.

New research published in the journal Aquatic Conservation: Marine and Freshwater Ecosystems by a team from the University of Helsinki in Finland suggests that beavers may indeed improve habitat for other animals. The scientists studied a series of 28 ponds, half of which were naturally colonized by beavers, and found that beaver activity – primarily flooding due to dam building – resulted in more waterbirds overall, as well as a more diverse waterbird population. The flooded ponds had about seven times as many insects – a prime food source for waterbirds – and were also shallower than the beaver-less ponds, both of which, the authors suspect, made the beaver ponds a more desirable habitat for waterbirds.

Where beavers move in, waterbirds tend to follow – and sometimes the beavers don't need a plane ride and a parachute to get there. 

Beavers fell trees, sometimes of considerable size, and combine them with mud and branches to build their dams.

(Image by D. Gordon E. Robertson via Wikimedia Commons)