A practical guide to bird watching in Sonoma County, California

(Unless otherwise indicated, all phone numbers are in the 707 area code)

This short, stocky, heron is hard to mistake for any other bird once you learn its shape. Mostly pale gray or white, but with a dark blue-green cap and back; heavy, pointed bill; proportionately large, red eye. The Peterson guides describe the cap and back as "black," but they are actually a very dark bluish-green that may look black in low light. The heavy, pointed bill, bright red eye, and typical posture are fairly distinctive (the bird usually keeps its neck tucked in). Legs ordinarily yellow but become pinkish during breeding season. The two head plumes are also a feature of breeding plumage (see photo above). Tends to stand still, hunched over, in or near water while hunting (often on tree roots near the water line), or perched higher in trees resting during the day (but usually near water). Becomes more active at dusk and forages at night. Often roosts colonially. I've seen as many as 60 together in the trees at the Laguna de Santa Rosa. Nests in rookeries with its own kind and with egrets and other herons. Santa Rosa's "Ninth Street Rookery" is a great place to see these birds in breeding plumage. Juveniles are an overall palish brown, but streaked on the breast, neck, and head, and spotted white on the wings (photo below). 

Superficially resembles Green Heron, and juveniles may resemble juvenile Great Blue Heron. Black-crowned Night Heron, however, is considerably larger than Green Heron (Butorides virescens, our smallest heron) and noticeably smaller than Great Blue Heron (our biggest). Green Heron stands about 18 inches tall (45cm), Black-crowned Night Heron about 25 inches tall (65cm), Great Blue Heron about 45 inches tall (115cm). Green Heron, while not really green, is rather differently colored (see photo below)--Note that bird's yellow eye, brown neck, striping in the wings, and greenish cap and back. The proportionately large, orange-red eye of Black-Crowned Night Heron is not shared by any other similar bird.

Further reading:

Bolander and Parmeter, Birds of Sonoma County California, rev. ed., 2000, p. 25

Brinkley, National Wildlife Federation Field Guide to Birds of North America, 2007, p. 153

Burridge, ed., Sonoma County Breeding Bird Atlas, 1995, p. 34

Dunn and Alderfer, eds., National Geographic Field Guide to the Birds of North America, 5th ed., 2006, p. 108

Dunn and Alderfer, eds., National Geographic Field Guide to the Birds of North America, 6th ed., 2011, p. 118

Ehrlich, Dobkin, and Wheye, The Birder's Handbook, paperback edition, 1988, p. 32

Fix and Bezener, Birds of Northern California, 2000, p. 66

Kaufman, Field Guide to Birds of North America, 2000, p. 158

Kaufman, Field Guide to Advanced Birding, 2011, pp. 187

Peterson, Birds of Eastern and Central North America, 5th ed., 2002, p. 50

Peterson, Field Guide to Birds of Western North America, 4th ed., 2010, p. 88

Peterson, Western Birds, 3rd ed., 1990,  p. 114

Sibley, Field Guide to Birds of Western North America,1st ed., 2003, p. 60

Vuilleumier, ed. Birds of North America: Western Region, 2011, p. 90

Voice: Cornell Lab of Ornithology: All About Birds--Black-crowned Night Heron




© Colin Talcroft, 2009, 2010, 2011, 2012, 2013

Unless noted, all photos by the author. If you would like to use one of my images, please ask for permission for non-commercial use with proper credit or commercial use with proper compensation.


For Comparison: Green Heron

Spring Lake, March 23,  2011

Immature Black-crowned Night Heron

Spring Lake, Santa Rosa, September 20, 2012

Note particularly the proportionately large red eye. The legs and base of the bill of this bird are stained an unusual color by blue-green algae

Black-crowned Night Heron, Lake Ralphine, January 10, 2012

1990-2013 Sonoma County data. Graph provided by eBird (www.ebird.org), generated May 30, 2013

EBird reported occurrence in Sonoma County

Black-crowned Night Heron

Nycticorax nycticorax