Great Cormorant (Phalacrocorax carbo)

 

Class: Aves
Order: Pelicaniformes
Family:    Phalacrocoracidae
Size:    Length: 30 to 40 inches (76 to 101 cm) Wingspan: 50 to 60 inches (127 to 152 cm)
Weight: 4 to 8 pounds (1.8 to 3.6 kg)
Diet: Fish, including flatfish, eel, wrasse, whiting and crab, but also frogs and water rats
Distribution: East coast of North America, New Zealand, coasts of Australia, Europe, Asia and Africa
Young:  3 to 5 chicks, once a year
Animal Predators:  Unknown
IUCN Status: No special status
Terms: Young: Chick
Lifespan: Up to 20 years

 

Facts/Trivia:

·     Cormorants are called “shags” in New Zealand.

·     Unlike other waterfowl, their feathers are not waterproof, so they can often be seen perching with their wings spread in order to dry them.

·     There are 32 species of cormorants worldwide.

 

Description

Great cormorants have a hooked bill and hooked claws. These large birds have black feathers and feet, with only a small patch of white at the throat. Their neck is long and thin. Both males and females are similar in appearance. 

 

Habitat

Great cormorants live mostly on coasts, but are sometimes found near inland rivers and lakes as well. They are widespread birds that can be found in and around New Zealand, from the east coast of Canada through to Florida, on the coasts of Australia, on the east, south and northwest coasts of Africa and in various parts of Europe and Asia. 

 

Feeding Habits

Cormorants eat several types of fish including flatfish, eel, wrasse, whiting and crab, but also frogs and water rats. Fish that cannot be swallowed whole are brought back to shore and torn into smaller pieces to eat. In ancient times in Asia, they were trained by humans to fish for them. They would dive beneath the water with a string attached to a leg and bring back a fish. Each fisherman would have several of these birds and made a living from fishing this way.

 

Reproduction

Cormorants are monogamous and take turns incubating the eggs. The female lays several pale blue, chalky-coated eggs in a nest made of twigs and seaweed. The nest is built within a tree or high on the rocky ledge of a cliff. The eggs hatch in approximately one month. Both parents bring food back to the chicks, who tap their parents’ beaks until the adult regurgitates the food into the throats of the offspring. The female seems very affectionate with her chicks, sitting in the nest among them and caressing them with her bill, while the little ones rub their heads against her. If a stranger approaches, she rises in alarm and flies back and forth, pretending to have a broken wing so that she may draw attention away from her chicks. The chicks are ready to leave their parents when they are about three-and-a-half months old.

 

Behaviour

These large, black water birds are great divers and swimmers that propel themselves under water with their large webbed feet, searching for fish to eat. They can stay underwater for up to 60 seconds and can dive as deep as 30 feet (9 m) down. They can also swim along just under the surface of the water with only their heads showing. Cormorants are fairly solitary by nature and only gather in flocks during migration times. 

 

Conservation

Great cormorants are the largest and most widespread cormorant species and are not of conservation concern.

 

Sources

http://www.birdsofbritain.co.uk/bird-guide/cormorant.htm

http://www.enature.com/fieldguide/showSpeciesGS.asp?curGroupID=1&curPageNum=50&recnum=BD0016

http://birding.about.com/library/fg/blfg-phalacrocoraxcarbo.htm

http://lavoieverte.qc.ec.gc.ca/faune/oiseaux_de_mer/html/great_cormorant.html

http://museum.gov.ns.ca/mnh/nature/nsbirds/bns0027.htm

http://www.mbr-pwrc.usgs.gov/id/framlst/Idtips/h1190id.html

Great Cormorant Wildlife Fact File, IM Pub, US

Ken Kaufman, Birds of North America, Houghton Mifflin, 2000

Harrison, C. and Greensmith, A. (1993). Birds of the World. London: Dorling Kindersley Limited