Last updated: May 21, 2021
Place
Pelagic Cormorant
Tim Hauf, timhaufphotography.com
Scientific Name
Phalacrocorax pelagicus
Introduction
This seabird is a small member of the cormorant family and is also known as Baird's Cormorant. Analogous to other smallish cormorants, it is also occasionally called the pelagic shag. Being one of the least social or gregarious cormorants, Channel Island National Park, due to its isolation from the mainland, provides an ideal environment for its breeding on all five channel islands. This seabird lives year round along the coasts of the Pacific; during winter it can also be found in the open ocean.
Quick and Cool Facts
- Their North American breeding range extends from Alaska to the Baja Pacific Islands in Mexico.
- Pelagic cormorants are the smallest of the North American cormorants.
- During the breeding season the skin under their eyes turns a vivid magenta.
- The pelagic cormorant is among the least gregrious or social of the cormorants, nesting on steep cliffs along rocky and exposed shorelines, either in loose colonies or far from nearest neighbors.
- A typical nest has between three and five eggs.
- The pelagic cormorant uses its own guano to solidify its nest materials and to cement its nest to the cliff face.
- They prefer to forage near kelp beds or among rocks.
- The feet of these expert divers are located far back on the body to give them forward thrust underwater.
- Pelagic cormorants can dive as deep as 100 feet.
- They can spring straight up out of the water into the air and fly.
- Pelagic Cormorants are not naturally water-proof and must spend time preening and grooming their feathers with oil collected from a gland at the base of the tail.
Appearance
The pelagic cormorant is the smallest and most delicate of the north Pacific cormorants. It is slender in appearance, with a long tail, a slim dark bill, and a head that is no wider than its neck. When in flight, the head and neck are held out in a straight profile parallel to the water. Basic plumage is black with a glossy iridescent green and violet-bronze on the body, and violet-purple on the neck. Breeding plumage is similar to basic plumage but also includes white flank patches, red facial skin at the base of bill, double head crests, and white plumes along the neck and upper-back region. Immature birds are dark brown, with the same proportions as adults. Other coastal cormorants are bulkier, with slower wingbeats.
Range
The pelagic cormorant's range extends from the Chukchi and Bering Seas south along the North American Pacific coast to Baja California, and along the Asian coast to southern China. The breeding range extends from north Alaska to the Aleutian Islands and south along the North American Pacific coast to Baja California, as well as, from the Bering Sea to Kurki Island and north Honshu, Japan. Its wintering range is from the Pribilof Islands to the Aleutian Islands and south along the North American Pacific coast to Baja California, as well as from the south Bering Sea along the eastern shores of Kamchatka and south to Hong Kong.
Habitat
The pelagic cormorant in central and southern California breeds on the rocky shores and cliffs along the coast, but substantial colonies breed on San Miguel, Santa Barbara, Anacapa, Santa Rosa and Santa Cruz islands from March to August. It is rarely seen farther than a few kilometers from land. As with all cormorants, due to their vestigal preen gland, their plumage is not waterproof. Thus, the birds return to a safe roost after foraging to preen and dry their feathers, typically adopting a spread-winged posture.
Feeding
Cormorants have high energy needs for swimming and flying, and they cannot fast for long periods or store much body fat. The pelagic cormorants energy needs are further exacerbated due to its small size, which demands that its roosting and nesting sites are in close proximity to its foraging sites. The Pelagic Cormorant feeds mainly on nonschooling medium sized fish, but also consumes invertebrates, maine worms and crustaceans. It forages near shore along rocky substrate, and in California it is frequently seen along the fringes of kelp forests. It feeds only during the day and for short periods of time. To catch prey it dives deeply; birds have been taken in fishing nets at depths of 180 feet. This species' small size enables it to spring directly from the water, rather than paddling along the surface as other cormorants are required.
Reproduction
About 25,000,pelagic cormorants breed along the Pacific coast of North America, excluding Alaska and the Aleutian Islands. About 60% of these are found in California. The initiation of pair formation and nest building varies geographically and relies heavily upon food supply. The southern range usually experiences earlier inititation dates, but on average breeding plumage is usually seen in February and nest building commences shortly thereafter.
The male will select a nest site and start nest construction and is then assisted by the female. Nest sites may be used for successsive years but may also change between years. Nest sites are usually on narrow ledges on steep rocky cliffs. Nesting material consists of mainly grass and seaweed, and material will be added to the nest until the chicks fledge. Nests are usually conpact and saucer shape, and guano acts as a cement to hold it together and to the cliff. The nest is repaired and improved in each season if need be; it can thus grow up to 5 ft., but it usually does not grow from year to year.
Egg laying usually takes place from early to late spring. Eggs are incubated between the feet and belly, and both sexes share incubation, brooding, and feeding duties. The clutch can range from 3 to 7 eggs but an average clutch is 3 to 4 eggs. Incubation lasts 3 to 4 weeks.
At hatching, the young weigh somewhat more than an ounce and are naked, but they soon grow sooty-grey down feathers. In normal years, all young of a typical clutch may be raised successfully and fledge at 40-50 days after hatching. They reach sexual maturity at two years of age, and a maximum age of almost 18 years has been recorded in the wild.
Migration
Birds that breed from Washington southward are permanent residents, but birds breeding farther north migrate to winter in northern Washington waters. Breeding colonies disperse but pelagic cormorants south of the Monterey Bay area do not migrate but continue to forage along the rocky coastal areas following the most abundant prey.
Conservation Status
Despite the fact that the population trend for the pelagic cormorant appears to be decreasing, the decline is not believed to be sufficiently rapid to approach the thresholds for vulnerable status. This numerous and widespread species has a very large range and is not considered threatened by the IUCN (International Union for Conservation of Nature). The bulk of its population is found in the relatively inaccessible waters of the Bering Sea region; about 50,000 each breed in the Kuril Islands, the Bering Sea islands, and the U.S. state of Alaska and its offshore islands (including the Aleuts). Regardless, local populations may be all but wiped out temporarily by oil spills, and on a larger scale competition with gillnet fisheries and drowning in such nets is putting a limit to its stocks. The impact of El Nino on weather and food may also affect the local populations as previously evidenced by historical records. Intrusion in nesting areas by fishermen, kayakers and divers can also be disruptive. Fortunately, most breeding sites in southern California, including Channel Islands National Park are protected areas for this bird.
Additional Information