Manitoba Bird Bird Atlas: Species At Risk

Common Nighthawk

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
Jun-01 Jun-11 Aug-01 Jun-06 Jun-11 Aug-01

Breeding Evidence

Common Nighthawks do not build nests; instead, they lay their eggs (usually two) on bare ground or gravelly surfaces. They will lay eggs on gravelled roofs. They breed throughout almost all of Manitoba except north of the treeline.

Habitat

Breeding Evidence Map

The Common Nighthawk is a tricky species to atlas properly because they are a very late arriving migrant and any May or early June records are best considered as migrants. Northern birds also return early in the fall and in early - mid August it is possible to observe flocks containing both local breeding birds and returning migrants. Sometimes these congregations consist of small, loose flocks that form at dusk to hunt insects over marshes, rivers, sewage lagoons and lakeshores. On occasion, very large flocks totalling thousands of birds are observed though this spectacle is sadly becoming an increasingly rare sight. For the above reasons, from late July onward, great care is required in assigning atlas codes for this species.

From June until mid July the most common form of breeding evidence is the booming display (a loud noise presumed to be given only by males created by wind passing over the wing feathers at the bottom of a display dive), that can be coded as S (singing – possible breeding). This behaviour should not be coded as D (display – probable breeding) unless two or more birds are observed together (several males displaying in close proximity and/or interacting with females). Wing clapping is also occasionally reported in this species. The nasal peent call also often heard should not be coded as S if heard in isolation, but rather H (habitat– possible breeding).

Common Nighthawks nest in a wide range of open habitats (images e to i); for example, dunes, beaches, recently harvested forests, burnt-over areas, logged areas, rocky outcrops, rocky barrens, grasslands, pastures, peat bogs, marshes, lakeshores, and river banks. They also inhabit mixed and coniferous forests. Nonetheless, although still quite common in parts of northern Manitoba, they appear to have declined substantially in southern Manitoba.

-from COSEWIC and The Birds of Manitoba (p. 238)