Careful observers may find American tree sparrows along the snow lined roads, and if they are lucky, longspurs or snow buntings. Many species of ducks, geese and swans use the refuge in winter, but their numbers are reduced compared to other times of year because of cold temperatures and few areas of open water. Check the display pond at Headquarters, the Blitzen River, Knox Pond and the Narrows. Search for Barrow's and common goldeneyes, and mergansers , as well as, the rare Eurasian widgeon . One of the highlights of winter are the large groups of tundra swans which are present in November, usually at Knox Pond.
Hundreds can gather in one area and their voices carry long distances.
Trumpeter swans may also be seen. Both species of swans may remain through the winter, but in smaller numbers. Raptors are present in the winter. Look for r ough-legged hawks and golden and bald eagles.