Cranes rely on open freshwater wetlands for survival during most of their lifecycle. The loss and degradation of these kinds of habitats are among the most pressing threats to the survival of these huge birds. Another threat, of course, is the ever-present danger of predators such as raccoons and mink.
The International Crane Foundation, founded in 1973, operates a 25 acre compound north of Baraboo, Wisconsin devoted to protecting this endangered species which are “the largest and oldest flying birds in the world,” according to ICF spokesman Dave Chesky.
About 20 acres are fenced and netted to protect the birds. Chesky says the site is home for over 120 cranes including every species. “We’re the only place that has all of them – whooping cranes, sandhill cranes, Siberian cranes – all 15 species.”
Most of the birds are part of a protected, captive flock; permanent, non-migratory cranes held in place by and overhead netting that keeps them from flying away. The perimeter fence that shields them from predators is an ingenious masterpiece of engineering created to keep some wily animals from gaining access to the rare birds.
Chesky described the protective perimeter this way: “To keep burrowing animals out, we’ve got a two-foot wide wire mesh buried two inches underground in front of the fence. The fence is eight feet tall with the first four feet made of one inch mesh chain link fencing. Over the years, we’ve learned to size it slightly smaller than a mink’s skull to prevent them from entering the area.”
The top four feet is a Gallagher supplied electric fence powered by B-260 chargers. “The chargers have proven very reliable,” said Chesky. “We just had one that was about 20 years old rebuilt by the factory and reinstalled it. It works perfectly.”
Wires are set just one inch apart at the bottom of this powered section and spaced wider at the top. The fence has ended the foundation’s losses to predators. “We haven’t lost a bird since it was installed,” said Chesky.