Bobolinks are cooperative feeders. Other adult birds, males or females, may join in the feeding of the young in a nest. The cause of this behavior is not known with certainty.
Bobolinks are about 7 inches long. In spring, the male is black with white shoulders and rump and yellow neck. In the fall its plumage changes to yellowish with brown streaks, looking more like the female. The tail feathers have pointed tips.
Habitat and behavior:
Bobolinks migrate at night from the north half of South America, where they spend November through March. They travel more than 6,000 miles up to the northern United States and Canada, where they stay during May through July. They uncommonly nest in Illinois; most pass through in the spring and fall.
Bobolinks prefer weedy fields in which clover, alfalfa, and mustard grow. A nest is made on the ground in a depression in the grass and lined with fine grass. A nest holds 3 to 7 eggs.
Bobolinks eat insects, seeds, grains, and fruit. In the southern United States, they eat rice from the fields, and in some places are considered a pest to agriculture.
These beautiful birds, like many native species, are a protected species.