A practical guide to bird watching in Sonoma County, California
(Unless otherwise indicated, all phone numbers are in the 707 area code)
Bitterns have been sighted in Sonoma County in all 12 months of the year, but they are uncommon and a good look at one is always a pleasure. Bitterns often are so well camouflaged and easily spooked that they're rarely seen except at a distance in dense stands of reeds or suddenly flying away from what might have been a good look--if only you'd realized sooner that a Bittern was standing right in front of you.
Sharp, heavy, pointed bill for catching aquatic vertebrates; distinctive, long neck that appears to be continuous with the rest of the body; neck and belly striped with ribbons of ochre finely edged in dark brown; white supercilium; white at the throat, but the head is otherwise striped, with the head and throat coloration separated by a streak of black; wings mottled brown; legs and underbelly pale. When attempting to evade notice, stands absolutely still, with its head pointing straight up. Unforgettable spring and early summer vocalization that is variously described. To me, it sounds like a repeated: glunk! ahloonk (Sibley calls it a "pounding bloonk a-doonk," Peterson describes it as "oong-ka' choonk"). Often makes a loud squawking noise when flushed, amid loud, rapid wingbeats. In flight, look for feet hanging out behind the tail, the bold ribbon-like striping on the body and neck, and dark flight feathers that contrast with the rest of the wing. Bittern is believed to nest in the county.
Once you've taken a really good look at the silhouette of American Bittern and remembered the striping (and heard the glunk! ahloonk), it's not easy to mistake this bird for anything else, but it may be confused with immature Black-crowned Night Heron (Nycticorax nycticorax). However, the young Night Heron has a rather squatter, hunched silhouette (like that of its parent); its proportionately large, orange eye is a give-away; and note the diffuse, overall pattern of grayish brown stripes, which are very different from the clear ribbons of ochre and brown on the neck and belly of the Bittern. The young Night Heron's wings appear fairly clearly spotted, while the Bittern's wings are mottled brown. A disturbed Black-crowned Night Heron is as likely as not to make no noise as it flies away. It won't say glunk! ahloonk in any circumstances. Green Heron is likely to be found in similar habitat, but that bird is smaller and rather differently colored (photo below).
Selected county sightings: Spring Lake (October 29, 2013); Spring Lake (January 9, 2012); Spring Lake (October 15, 2011); Spring Lake (September 29, 2011); Spring Lake (April 16, 2011); Spring Lake (January 6, 2010)
Further reading:
Bolander and Parmeter, Birds of Sonoma County California, rev. ed., 2000, p. 23
Brinkley, National Wildlife Federation Field Guide to Birds of North America, 2007, p. 152
Burridge, ed., Sonoma County Breeding Bird Atlas, 1995, p. 29
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. 112
Dunne, Pete Dunne’s Essential Field Guide Companion, 2006, pp. 127-128
Ehrlich, Dobkin, and Wheye, The Birder's Handbook, paperback edition, 1988, p. 32
Fix and Bezener, Birds of Northern California, 2000, p. 60
Floyd, Smithsonian Field Guide to the Birds of North America, 2008, p. 110
Kaufman, Field Guide to Birds of North America, 2000, p. 158
Lukas, Bay Area Birds: From Sonoma County to Monterey Bay, 2012, pp. 57-58
Parmeter and Wight, Birds of Sonoma County California, Update (2000-2010), 2012, p. 18
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. 55
Stokes, Stokes Field Guide to the Birds of North America, 1st ed., 2010, p. 124
Vuilleumier, American Museum of Natural History, Birds of North America: Western Region, 2011, p. 89
Voice: Cornell Lab of Ornithology: All About Birds--American Bittern
© 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: Immature Black-crowned Night Heron
Ninth St. Rookery, Santa Rosa, 2011
American Bittern, Spring Lake, Santa Rosa, October 29, 2013
American Bittern: Spring Lake, Santa Rosa, April 16, 2011
American Bittern in flight, Spring Lake, Santa Rosa, January 9, 2012
American Bittern
Botaurus lentiginosus
1990-2013 Sonoma County data. Graph provided by eBird (www.ebird.org), generated May 30, 2013
EBird reported occurrence in Sonoma County
For comparison: Green Heron
Spring Lake, Santa Rosa, October 29, 2013
