WASHINGTON – One spring afternoon in 2015, biologist Thomas Gable followed signals from a gray wolf’s GPS tracking collar to a small stream in Minnesota’s Voyageurs National Park.
There he found a large canine paw print in the mud and tufts of wolf and beaver fur caught in low bramble. A beaver had fallen victim to a wolf, Gable deduced.
The industrious rodent's work in progress stood nearby — aspen logs, stripped clean, spanned the stream, and a pond about a foot deep was forming behind them.
But when Gable checked again 10 days later, the dam had begun to collapse. With no aquatic engineer to repair the structure, the pond had disappeared. “The water had totally vanished,” said Gable, who is based at the University of Minnesota.