The Long-winged Harrier searches for prey over wetlands and grasslands in South America. Plumage differs by sex, and birds occur in light and dark forms.
Females are often larger than males. Males are mostly black above, with grey-and-black barred wings and tails; females have brown where much of the male's black is found. Light birds have white bellies, while dark birds have black bellies.
It hunts between sunrise and sunset, mainly for small mammals, and also takes small reptiles, amphibians, and birds. Some populations migrate, while Trinidad and Tobago and much of Brazil have year-round residents.
An extinction-risk assessment has not been added yet.