Ondatra zibethicus
A small marsh rodent whose tail leaves a wavy line between its prints.
1–1.5 in hind, ~1 in front. Five long spindly hind toes with stiff hairs. Front print shows four toes. Snaking tail drag down the middle. Muddy runs along bank edges.
Marshes, ditches, ponds, slow rivers. Most of North America.
Nocturnal and crepuscular
Cattails, rushes, mussels, crayfish
Muskrats build cattail lodges that ducks later nest on top of.
Should I be concerned?
Harmless; avoid handling.