Beavers

Under cover of darkness, beavers are swimming through tranquil pools in the San Pedro River. They're gnawing on tree trunks. They're building dams.

We know this because of the work of volunteers who have recently walked miles along the river searching for signs of beavers.

Next to the piled branches of one beaver dam, a volunteer strapped a wildlife camera to a tree several months ago. And in the middle of the night, two beavers repeatedly turned up in the infrared images, their eyes glowing in the darkness.

If you picked the Beavers in your bracket, you can probably forget about winning your office basketball pool.

But if you’re betting on the beavers along the San Pedro River, you’re still in luck.

A Tucson-based environmental group says the dam-building rodents are doing better than previously thought on the federally protected river southeast of Tucson, where they were reintroduced 20 years ago after being wiped out in the early 20th century.

Thousands of beavers once populated Southern Arizona’s rivers, with frontiersman James Ohio Pattie dubbing the San Pedro River as “Beaver River.” But the animals were hunted and trapped to extermination in the 1800s and early 1900s. However, in 1999 the Bureau of Land Management released 16 beavers into the San Pedro Riparian National Conservation Area. Since then, the population has ebbed and flowed, with 50 beavers now estimated along the San Pedro.