The most readily seen mammal at the refuge is the nutria, a species that was introduced into the Northwest in the 20th century. Depending on my luck and what time of year I visit, I've also seen beaver, coyotes, deer, mink, moles, muskrats, otters, rabbits, raccoons, and weasels. You might also see some of the small rodents that many of the predators feed on, from little mice to larger voles. These little critters are easiest to see when they have been captured by the herons, egrets, hawks, owls, and coyotes that feed on them.
|You'll see the handiwork of the beavers on the trees of the refuge more than you'll see beavers themselves, but on rare occasion you may be treated with a view of these amazing creatures.||Blacktails aren't commonly seen at the refuge, but keep your eyes peeled at the entrance to the refuge as well as the meadows after you pass the Quigley Lakes.|
|While both the River S Unit and Carty Units are home to coyotes, I've only seen them on the auto tour of the River S Unit. Sometimes they're quite a ways away, but on a number of occasions I've seen them up close.||Although not commonly seen, you might catch a glimpse of the thin little predators on the auto tour.|
|I've mostly seen muskrats in the spring, when they seem to be especially active both eating and carrying plants back to their dens. I've met them just about everywhere around the auto tour and on the Kiwa Trail.||Nutria are not native to the Pacific Northwest, but now that they are here they are thriving. Nutria are the most likely mammal you'll see at Ridgefield.|
|River otters can be seen at both the River S and Carty units, usually in groups of two or three or four or more.||Like nutria, eastern cottontails are not native to the Northwest, but they are the only rabbit you're likely to see at the refuge.|
|I rarely see raccoons at the refuge and have photographed them even less, but I always love seeing these masked mammals.|