Bird watching is best during the spring and fall migrations.
Principal spring bird attractions
include the courtship dance of the western grebe, courting behavior of many duck species and
nesting Canada geese. Least bitterns and green-backed herons also nest here but are very hard
to observe. Late summer and fall feature a buildup of cormorants, white pelicans, and great egrets.
Large numbers (up to 100,000 or more) of Franklin's and ring-billed gulls roost on Lake Tewaukon
in September. From mid-October to freeze-up, large numbers of waterfowl move through the refuge,
with peaks of up to 700,000 snow geese; 23,000 Canada geese; 60,000 mallards; 13,500 lesser scoup,
and 2,000 tundra swans recorded since 1980.
The following list contains 236 species compiled by refuge
personnel. Seven other species considered
accidental are added at the end of the list. Species names are in accordance with the Sixth A.O.U. Checklist.