Mallards hang onto the north country as long as they can, before the migrate south
The Refuge is home year-round to many species of wildlife and is visited by many migratory birds during the spring and fall. The Refuge checklist includes 227 birds, 36 mammals, 6 reptiles, 3 amphibians, and 11 fish species.
Large flocks of birds utilize Lake Ilo in the spring and fall. Peak concentrations can reach 100,000 waterfowl in the fall and 20,000 in the spring. The principle waterfowl nesting species are Canada geese, mallards, pintails, blue-winged teal, shovelers, and gadwall. Other nesting marsh and waterbirds include eared, western, and pied-bill grebes; double-crested cormorants; great blue herons; black-crowned night herons; and American bitterns. Shorebirds, such as killdeer, plovers, sandpipers, willets, yellowlegs, marbled godwits, American avocets, and phalaropes are plentiful during migration.
Some songbirds, such as meadowlarks, sparrows, and swallows, are easily seen from roads, while others are best found by hiking and quietly observing. Ring-necked pheasant are common, while sharp-tailed grouse and gray partridge are not as plentiful. The Refuge is home to white-tailed deer, badger, skunk, beaver, raccoon, mink, and muskrat. It is a special treat to see the less common pronghorn antelope, mule deer, coyote, and secretive weasel on the Refuge.