A weasel stands on a log carrying a mouse at night. Weasels are notoriously difficult to capture on camera, and researchers are working to find the best way to draw them out of hiding.

The least weasel, as the name suggests, is a bit smaller. It's only found in the mountains. In general, weasels may be small in stature but they play a big role in the ecosystem.

A weasel stands on a log carrying a mouse at night. Weasels are notoriously difficult to capture on camera, and researchers are working to find the best way to draw them out of hiding.