Pelagic Cormorant (Phalacrocorax pelagicus)

Pelagic Cormorant

Subspecies

Monotypic species

Genus

The cosmopolitan genus Phalacrocorax of the Suliformes family includes thirty-five species frequenting coasts and islands. The face and throat are naked; the bill is long, and the upper mandible much curved at the point, while the lower supports a dilatable membrane which forms a gular pouch. The legs are short, strong, and abdominal, with three toes in front and one behind, all united; the claw of the middle toe is pectinated and probably used to dress the plumage and to free the bird from insect pests. The wings are of moderate length, and the tail-feathers stiff and rigid. Many of the species develop crests or wattles in the breeding season. These birds feed exclusively on fish. All Cormorants, Shags and Darters have a small bone at the back of the skull, the occipital style. This bone is flexibly attached to the skull and is supposed to have a function for the grasping ability of these birds. The ramphotecal coating of the bills of the cormorants are divided in plates, very much like those of the tubenoses, without visible nostrils.

Physical charateristics

Noticeably smaller and more iridescent than other coastal cormorants, with more slender neck, small head, and much thinner bill. When breeding (Februaryendash June) it has a double crest and a white patch
on each flank. Throat patch and part of face dull red (obvious only at close range). Deep brown all over, darkest on back. Note the thin bill.

Listen to the sound of Pelagic Cormorant

[audio:http://www.aviflevoland.nl/sounddb/P/Pelagic Cormorant.mp3]

Copyright remark: Most sounds derived from xeno-canto

wingspan min.:	100	cm	wingspan max.:	120	cm
size min.:	55	cm	size max.:	70	cm
incubation min.:	27	days	incubation max.:	35	days
fledging min.:	28	days	fledging max.:	35	days
broods:	1		eggs min.:	3
			eggs max.:	6

Range

Pacific Ocean : North coasts

Habitat

Coast and bays. On ocean, usually rather close to shore, sometimes well out to sea. Favors rocky bays, areas of deep water near base of cliffs. Nests on islands or coasts on narrow ledges, steep slopes, other inaccessible locations.

Reproduction

Nests in colonies. Male displays at nest site with bill pointed up, tail down, quickly raising and lowering tips of folded wings so that white flank patches appear to flash rapidly.
Nest:
Site is on cliffs with near-vertical slopes, narrow ledges. Parents not effective at defending eggs or young, rely on inaccessible location for protection. Nest is of seaweed, grass, moss, sometimes sticks. Both sexes help build nest; may use same nest e
ach year, adding to it annually.
Clutch 3-5, sometimes 1-7. Bluish white, becoming nest-stained. Incubation is by both sexes, 26-37 days, typically about 30. Young:
Probably both parents feed nestlings. Young may be capable of short flights at 35-40 days, leave nest at about 45-55 days (much variation). Parents may tend and feed young for a few weeks after they leave nest. 1 brood per year.

Feeding habits

Fish, crustaceans. Eats mainly small fish, including sculpin, herrings, greenlings, sand lance; also many crabs, shrimps. Also eats marine worms, amphipods, algae.
Behavior:
Forages by diving from surface and swimming underwater, propelled mainly by feet, though may sometimes use wings as well. Forages singly, although may be attracted to concentrations of other feeding birds. Known to dive to at least 120′ below surface; ta
kes much of food from near bottom in rocky areas. Eyes adapted for vision in water as well as in air.

Conservation

This species has a very large range, and hence does not approach the thresholds for Vulnerable under the range size criterion (Extent of Occurrence <20,000 km2 combined with a declining or fluctuating range size, habitat extent/quality, or population size and a small number of locations or severe fragmentation). Despite the fact that the population trend appears to be decreasing, the decline is not believed to be sufficiently rapid to approach the thresholds for Vulnerable under the population trend criterion (>30% decline over ten years or three generations). The population size has not been quantified, but it is not believed to approach the thresholds for Vulnerable under the population size criterion (<10,000 mature individuals with a continuing decline estimated to be >10% in ten years or three generations, or with a specified population structure). For these reasons the species is evaluated as Least Concern.

Migration

Mostly sedentary, with post-breeding dispersal; northernmost populations of NE Siberia and NW Alaska migratory. Winter visitor to Korea and China. Vagrant to Hawaii.

Distribution map

Pelagic Cormorant distribution range map

Planet of Birds