Double-crested Cormorant Phalacrocorax auritus

Identification Tips: 

• Length: 27 inches Wingspan: 50 inches 
• Sexes similar 
• Large, dark waterbird with a long, hooked bill and long tail 
• Long, thin neck 
• Gular area squared off and orange, extending straight down across throat
• Orange lores 
• Often perches with wings spread to dry them 

Adult:

• Entirely black plumage 
• Small white plumes on head during breeding season 

Immature:

• Pale throat and chest darkening below to dark belly; some individuals are entirely pale underneath
• Brownish back and upperwings 

Similar species: 

• Loons are similar on the water, but lack hooked bills. Anhinga has a long, pointed bill and a much longer tail. All adult cormorant species in the U.S. are separable by the shape and color of the gular areas. No other species has orange lores and gular region that does not form a point at the gape. Neotropical Cormorant can be similar but is slimmer and longer-tailed, and has a differently shaped gular area. Great Cormorant is also similar but has a yellowish, pointed gular area surrounded with white as an adult. Immatures are dark-chested and pale bellied, unlike Double-crested. 
• Length and wingspan from: Robbins, C.S., Bruun, B., Zim, H.S., (1966). Birds of North America. New York: Western Publishing Company, Inc.

For Wading Birds, Survival Depends on Annual Cycles of Drought and Flood

One of the more spectacular and, at the same time, predictable avian events in Everglades National Park is the tremendous increase in numbers of wading birds (herons, egrets, ibis, storks, etc.) that congregate each year during the dry season, November through May. Between 50,000 and 100,000 wading birds collect in the expansive freshwater and estuarine wetlands of the park, attracted by the excellent feeding conditions created by the drying marshes. Beginning with the shallowest areas -- those that dry first once the summer rains have ended -- the flocks of waders follow the retreating water line in search of trapped and concentrated fishes, crayfish, prawns, and other aquatic organisms. By late in the dry season, usually March to April, these feeding flocks have moved into the deeper central marshes of the Shark River Slough. In these core refugia of the Everglades, park scientists have recorded densities as high as 600 fish per square meter. The movement of these birds eventually becomes a pest on privately owned property.