Circus

Circus is a genus of birds of prey in the family Accipitridae, whose members are known in English as harriers. Harriers are distinctive, long-winged, long-tailed raptors that hunt characteristically by flying low and slow over open grassland and marsh, using a combination of keen low-altitude flight and, unusually among diurnal raptors, an owl-like facial disc thought to aid in locating prey such as small mammals, reptiles, and birds by sound as well as sight. Juvenile harriers are sometimes called ring-tail harriers for their banded tail pattern. Fossil and molecular evidence suggests the genus diversified alongside the global spread of grasslands and the rise of C4 grass ecosystems roughly six to eight million years ago, during the Late Miocene and Pliocene epochs, a period that reshaped open-country habitats worldwide.