Manitoba Bird Bird Atlas: Species At Risk

Bobolink

Early Breeding and Last Migration Dates

South: Regions 1 to 8 Central: Regions 9 to 12 North: Regions 13 and 14
Early Breeding Last Migration Late Breeding Early Breeding Last Migration Late Breeding Early Breeding Last Migration Late Breeding
May-16 May-21 Jul-21

Breeding Evidence

Displaying males perch on fence posts or tall plants; and periodically flutter above the perch to sing (images a and b). In spring and summer, Bobolinks form loose colonies of up to 20 birds.

Habitat

Breeding Evidence Map

Bobolinks’ breeding range covers the agricultural regions in Southwestern Manitoba below the diagonal running from Swan River (possibly The Pas) in the north to the edge of the boreal forest in the southeast near Sprague. In the Interlake region, they are locally common from Oak Hammock Marsh northward to Hecla Island, Hodgson, and Gypsumville.

The breeding range is associated with grassland but also with agriculturally developed land including alfalfa fields and lush pastures. Bobolinks can also be found on the grassy margins of large wetlands (Oak Hammock Marsh). The Bobolink’s ability to utilise a variety of croplands makes this species more common in Manitoba than any of the other threatened grassland songbirds.

Nests are built on the ground, usually well concealed like those of other grassland sparrows (see Baird’s Sparrow). Nests are often found in alfalfa and hay fields; however, these fields are typically mown before the end of June when the nests still contain eggs or small nestlings.

-from COSEWIC and The Birds of Manitoba (p. 373)