River Otter, Muscatatuck National Wildlife Refuge, IndianaRiver otters spend most of their time in the water, playing and hunting for food. They do, however, build dens. And by build, I mean they find another animal’s abandoned den and take it over by adding a few twigs and other nesting material. I was lucky to stumble upon this otter’s secret spot, almost fortress-like, in all those thin tree trunks in a swampy area adjacent to a pond. Photographed in southern Indiana. Nikon D200 with Nikkor 600mm f/5.6 manual focus lens, ISO 800, f/5.6 at 1/60th of a second.