Compared to the graceful, long-limbed anatomy of many herons and egrets, black-crowned night herons (Nycticorax nycticorax) are certainly among the stockier and squat members of the family Ardeidae. But despite their comparatively compact forms, these birds occupy habitats ranging from the upper western plains of Canada, all the way to the southern tip of South America, as well as parts of Africa, and Asia. They are the most widespread heron species in the world. But habitat loss and the effects of DDT and other pesticides in the mid-twentieth century have caused the worldwide population to decline.
As their common name implies, these birds are active at night, when they leave their day roosts to forage in wetlands. Like other herons and egrets, the black-crowned night heron is a wading bird, standing motionless, or slowly walking near the edge of shallow water looking for prey, like fish, crustaceans, aquatic insects, frogs, snakes, and sometimes other birds.
During the day, while normally seen in the hunched and motionless state seen in today’s photo, the grey and bluish-black plumage is quite striking. In breeding season, the adults display a long white streamer of plumage down the back, often extending beyond the end of the tail.
Today’s photo was taken with a Canon EF28-135 mm f/3.5-5.6 IS USM lens zoomed to 95 mm on a Canon EOS 5D Mk III. The exposure was set to 1/1000 sec at f/6.7 and ISO 400.
Sources:
https://www.allaboutbirds.org/guide/Black-crowned_Night-Heron/id
http://www.audubon.org/field-guide/bird/black-crowned-night-heron
http://www.nj.gov/dep/fgw/ensp/pdf/end-thrtened/bcnightheron.pdf