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Brandt's Cormorant
Phalacrocorax penicillatus
Family: PHALACROCORACIDAE
Order: Pelecaniformes
Spanish Common Name: Cormorán de Brandt, Sargento guanero
French Common Name: Cormoran de Brandt
(c) Glen Tepke |
Courtesy Kenn Kaufman |
Annual Population Indices |
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Conservation Status
Global Population: 227,000
Continental Population: 227,000
Watchlist Status: 
Audubon State of the Birds Status: moderate population declines, small range
The Brandt's Cormorant inhabits marine environments along the Pacific Coast. This large, gregarious bird often feeds, flies, roosts, and nests in large groups. When nesting, the guttural croaks of this relatively quiet North American cormorant are barely audible more than a few feet away. The bird is named for J. F. Brandt, a Russian naturalist who first described the bird in 1838.
Range & Distribution
Brandt’s Cormorants breed along the Pacific Coast from southern British Columbia southward to Baja California. In the main part of their range, from California to Washington, the cormorants depend upon the rich food sources resulting from the upwelling of the California Current. In the non-breeding season, the effects of this current diminish, and Brandt’s Cormorant populations redistribute along the coast from southern Alaska southward to Baja California, wintering wherever food is locally available.
A legend for the range map to the right can be found here.
Population Status & Trends
While local populations fluctuate, overall numbers seem stable; CBC data shows increased numbers. In California, Brandt’s Cormorants are common; over 3/4 of the world’s population resides here. The highest numbers are in central California, followed by southern, and then northern California. A distributional shift from islands to coast, with consequent declines in the Farallon Islands and increases at coastal colonies, has been suggested. In Oregon, the birds are common, but distribution is discontinuous. Population growth since the 1970s may be due to protection from shooting and colony-raiding by fishermen. In Alaska and Washington, the birds are uncommon; in Mexico, they are locally common on the Pacific Coast. British Columbia also hosts a few active colonies.
An explanation of the Annual Population Indices graph displayed to the right can be found here.
Conservation Issues & Efforts
Brandt’s Cormorant colonies vary from year to year, both in size and location. The largest colony is in California’s Farallon Islands. From about 7,500 pairs around 1860, only a few thousand cormorants were left by the early 1900s, due to disturbance by murre egg collectors. Fishermen also shot cormorants, blaming them for salmon declines. Legal protection boosted California populations in subsequent decades. By 1974, the Farallon Islands breeding population had increased to about 11,900 pairs; but in 1983, the population plummeted once again, this time due to El Nino’s ocean warming effect. Populations have since fluctuated. Recovery has been slowed by the growth of fisheries and California sea lion populations, and by gill-net mortality until 1987, when gill-netting was outlawed. In 1993, a 300-foot exclusion zone during breeding was established around the Farallon Islands. Future expansion of California groundfish fisheries could reduce the young fish available for cormorants. Further research is recommended.
Other challenges to Brandt’s Cormorants include pesticides and oil pollution. During incubation, Brandt’s Cormorants are vulnerable to disturbance from fishing, diving, boating, and even visitation for research or educational purposes. Repeated flushing from nests can result in near-total egg loss and colony desertion. However, the establishment of a productive new colony on Alcatraz Island, CA suggests that, given good ocean conditions and public access restrictions, Brandt’s Cormorants can persist even in high-disturbance areas.
In Oregon, most nesting habitat is now protected in three national wildlife refuges; however, surrounding waters undergo heavy recreational use. In California, nearly all coastal islands are protected as refuges, parks, or ecological reserves.
What You Can Do
Join beach cleanups in your area. Properly discarding of debris, particularly plastic, will prevent cormorants and other waterbirds from eating it.
Don’t discard used oil into city sewers or municipal water supplies. It can end up in the ocean where cormorants rest and feed.
Dispose of monofilament lines, hooks, and fishing lures properly; cormorants can become entangled in this gear.
Don’t disturb nesting cormorants when hiking or boating; prevent dogs and children from disturbing them. Brandt’s cormorants are particularly sensitive to disturbance near the nest; when scared from their nests, gulls will frequently feed on their eggs and young.
For actions you can take, including Audubon activities, please visit our resources page.
For More Information
References
Kaufman, Kenn. 1996. Lives of North American Birds. Houghton Mifflin Company, New York.
Sibley, David Allen. The Sibley Guide to Birds. Alfred A. Knopf, Inc., New York, 2000
Wallace, E. A. H., and G. E. Wallace. 1998. Brandt’s Cormorant (Phalacrocorax penicillatus). In The Birds of North America, No. 362 (A. Poole and F. Gill, eds.). The Birds of North America, Inc., Philadelphia, PA.
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