Organisms / Animalia / Craniata / Aves / Ciconiiformes
/ Phalacrocoracidae / Phalacrocorax / Species
||Common cormorant, Large
cormorant, Aalscholver (Dutch), Grand Cormoran (French), Kormoran (German), Cormorán
grande (Spanish), Storskarv (Swedish).
- Adult: Eye emerald green, Bill
grey with culmen
black and lower mandible
base yellow, legs black. Upperparts and
underparts metallic blue-glossed black, short crest. Chin and sides of
head white patch, crown,
upper neck, lower throat variable elongated white feathers, base of leg
white patch. Wings black, with secondaries
outer webs bronzed.
- Juvenile: Eye brown, Bill
yellow with darker culmen,
legs black. Plumage More brown, with underparts variably
- Nestling: Eye grey-brown, Bill
pink with black tip, legs brown-black. Naked initially skin
brown-black, black down from six days old
|Range and Habitat
- Phalacrocorax carbo carbo Eastern Canada,
Greenland, Iceland to Norway and British Isles.
- Phalacrocorax carbo sinensis central and
southern Europe, east to India and China.
- Phalacrocorax carbo hanedae Japan.
- Phalacrocorax carbo maroccanus north-western
- Phalacrocorax carbo lucidus coastal western and
southern Africa, and inland East Africa.
- Phalacrocorax carbo hovaehollandiae Australia
(including Tasmania), New Zealand, Chatam Islands.
In the London
Area, a breeding resident, for example at Walthamstow reservoirs
and Broadwater Lake. Counts of over 200 birds are regular at Walthamstw,
Queen Mary, Staines, Wraysbury, Queen Elizabeth II and Walton reservoirs,
and is also seen in Inner London,
for example seen at 14 sites during 2000, with 30 birds visible on the
Thames at Lambeth Bridge in early March. (J322.65.w1)
Movement: northerly populations migratory
or partially migratory
(e.g. Canadian and Greenland birds may reach New Jersey, even Florida), elsewhere sedentary
Habitat: Marine (sheltered areas, estuaries and coasts)
and inland open water - lakes, reservoirs, wide rivers, flood waters etc.
- Food: fish, also crustaceans and amphibians.
- Feeding: Mainly pursuit-diving.
- Breeding: Temperate northern hemisphere mainly April to
June, but all year in tropics. Colonial breeder, often mixing with other colonial species
for breeding (cormorants, herons, darters, spoonbills, ibis). Nest on cliff ledges, on
ground among boulders, trees, bushes, reedbeds, also on bare ground and on human
structures. Nest of sticks, reeds, seaweed, with finer lining, built by both parents, male
mainly supplying material. 2-6 (average 3-4) eggs, incubation 27-31 days (B107),
28-31 days (B104),
cared for and fed by partial regurgitation by both parents (once by each parent each day),
continually initially, fledge about 50 days but cared for a further 50 days. One brood,
may re-lay if eggs lost. Occasionally sexually mature by two years old, usually 3-5
- Breeding behaviour: Seasonal monogamous
pair bond, may be longer lasting.
- Social behaviour: Often gregarious,
sometimes form large fishing flocks.
(B1.w3, B2, B104, B107)
(See also Population
Control of Birds - General)
Organisations (UK Contacts):
Electronic Library (further reading):