By Caroline Patterson

Between blizzards, pale sunlight falls on the white feathers and black bills of thousands of geese at Freezout Lake Wildlife Management Area, an 11,350-acre site about 15 miles southeast of Choteau, Mont., on Highway 89. As many as 100,000 lesser snow geese—along with Ross's geese, blue geese, and tundra swans—swim, flap their wings, and fill the chilly air with a symphony of honks.

In the calendar of the Blackfeet, spring is "when the geese come." And no place is busier than these wetlands on the Pacific Flyway between the Rocky Mountain front and the barley fields in the Greenfields Bench area of northern Montana. Snow geese arrive in waves from as far away as California's Central Valley to rest and fatten up before heading north to lay eggs and rear their young in the Arctic tundra of Alaska and Canada. During their stay, usually lasting four days, they lift off en masse twice daily to feed in nearby fields, a spectacle of sight and sound that wows even the most jaded observers. (406) 467-2646, publiclands.org/explore/site.php?id=2841.