Northern Harrier

The northern harrier is a hawk-like bird I've seen before but had no familiarity with and so knew nothing about it. It was not until seeing them several times in the last year at Bear River Migratory Bird Refuge (but got no photos), then seeing migratory birds near the Salton Sea that I've gotten photos and gotten to know what they look like. 

This is probably my best photo. Note the white patch on the rump and the owlish face. 

Females are heavier and larger than males. It has the longest wing and tail relative to its body size of any raptor in North America. They hunt primarily small mammals like voles, cotton rats and ground squirrels, but will also prey on birds, amphibians, reptiles and insects. 

Flying near cattails gave it a nice contrast and gave a better photo. 

They have a white rump and an owl-like face that helps them detect prey by hearing. Adult males are more grayish above with a dark trailing edge on the wings and are pale below. Females are pale below, but have brown streaking. 

These poor photos taken in September provide coloration and the white rump stands out. 

They breed in the northern part of the northern hemisphere in Canada and the northern U.S., then migrate to the southernmost U.S., Mexico and Central America. They are year-round residents of milder regions in the southern U.S. I'd never seen them before near the Salton Sea and saw a couple of them in early September and 6 or 8 of them in October 2021.