Pelagic Cormorant

The Pelagic Cormorant has glossy dark plumage and a small, thin, dark bill.

– White flank patches.
– Tufts on crown and nape.

Photograph © Greg Lavaty

Sexes similar.

Winter birds lose the white flank patches and tufts.

Juveniles resemble winter adults but are brown.

Coastal areas.

Fish and crustaceans.

Forages by diving.

Breeds on the west coast of Alaska, Canada, and the U.S. Leaves the northern portion of the breeding range in winter.

The Pelagic Cormorant is the smallest West Coast cormorant .

Wing and head waves are used as an aggressive display by a territorial bird.

Groans, croaks, and hisses are given on the breeding grounds.

The nest is a mound of plant material placed on a cliff.

Number: 3-5.
Color: Whitish.

Incubation and fledging:
– Young hatch at 26-37 days.
– Young fledge (leave the nest) in 45-55 days after hatching but remain with the adults for some time.

Published by the Smithsonian Institution between the 1920s and the 1950s, the Bent life history series of monographs provide an often colorful description of the birds of North America. Arthur Cleveland Bent was the lead author for the series. The Bent series is a great resource and often includes quotes from early American Ornithologists, including Audubon, Townsend, Wilson, Sutton and many others.

Bent Life History for the Pelagic Cormorant – the common name and sub-species reflect the nomenclature in use at the time the description was written.

I have never been able to recognize any constant characters by which the two northern forms of the pelagic cormorant, pdagicus and roliustus, could be satisfactorily separated. And if the two forms are subspecifically distinct, the breeding ranges of the two have never been satisfactorily separated. The birds of southern Alaska seem to be identical with those of the Aleutian Islands and the birds of the American coast of Bering Sea seem to be similar to those of the Asiatic coast. Therefore Pho]acrocora~2i peUzgicus ro7ustus seems to have no standing. For these reasons and because I am unable to satisfactorily separate the references between the two forms, I prefer to treat them both together, for certainly their life histories are similar. I shall use the name pelagic cormorant to cover both forms.

Nesting: Tbroughout the whole length of the Aleutian chain we found this small, slender cormorant sitting in little groups on the rocks about the promontories or flying out to meet us and to satisfy their curiosity by circling about our boat; they seemed far from timid and were but little disturbed by our frequent shooting for they returned again and again to look us over. Here they breed in colonies on the highest, steepest and most inaccessible rocky cliffs, safe from the depredations of foxes and men and shrouded in the prevailing fogs of that dismal region. The nest is placed on some narrow ledge on a perpendicular cliff facing the sea; it is made mainly of seaweeds and grasses, is added to from year to year and becomes quite bulky.

On the Siberian coast their nesting habits are similar; Dr. J. A. Allen (1905) quotes Mr. N. G. Buxton’s notes as follows:

At this place, and six miles farther south, at Matuga Point, there are several rocky islets with precipitous sides where thousands of them nest. Their nests are placed in the most inaccessible places on top of ledges and projections. The nests are large and bulky and composed of kelp and seaweed. The eggs are chalky-white, with a bluish tinge. Five to seven constitute a clutch. The eggs are not palatable on account of the strong flavor, although the Koraks gather and eat them. The height of the nesting season Is reached by the 10th of June. The males assist in the work of incubation in southern Alaska the pelagic cormorant was found breeding abundantly at various localities by all of the expeditions sent to these regions. Dr. Joseph (irinnell (1909) quotes Mr. Joseph Dixon’s notes, referring to South Marble Island in Glacier Bay, as follows:

There were at least a hundred cormorants breading on the island and from one bundled and fifty to two hundred more were merely roosting tbere. Only breeding birds were seen during the day, hut about 7 o’clock the other black nonbreeders began to arrive in bunches of from four to seven. They left about 4 o’clock in the morning. The nests were attached to the sloping marble just before it dropped off Into salt water and were from fifteen to seventy-five feet above the high-tide mark. Most of the nests were not finished, but four contained one egg each. Tile nests were compactly built of moss gathered nearby, and not of seaweed. The white patches on the flanks and the two crests were very noticeable in the breeding birds, and most of the males also had the white, slender plumes on their xiecks. The nonbreeders had no white flank patches.

Mr. George Willett (1912) says that at St. Lazaria Island “the nests arc built of sticks and seaweed, lined with grass and seamoss. Many of the breeding birds have little or no white on the flanks, and in many cases the nuptial plumes on the neck are not present or are very poorly developed.”

Eggs: The pelagic cormorant is said to lay anywhere from three to seven eggs, but the usual numbers run from three to five, the larger numbers being exceptional. They are “elliptical ovate” or “elongate ovate” in shape. The color is very pale blue or bluish white, which is more or less concealed by a thin calcareous deposit, originally white, but usually somewhat nest-stained. The measurements of 41 eggs from the supposed breeding range of pelagicus, average 58.3 by 37.4 millimeters; the eggs showing the four extremes measure 63 by ~8, 61 by 41, 53.3 by 37, and 56 by 35 millimeters. The measurements of 43 eggs from the supposed breeding range of vobustus, average 57.5 by 37.2 millimeters; the eggs showing the four extremes measure 63 by 39, 62 by 39.5, 51.5 by 36, and 55.5 by 34 millimeters.

Plumages: The period of incubation is 26 days. The young bird is naked when first hatched, but before it is half grown it is covered with short thick down of a dark, sooty gray color. The wings and tail appear first and are fully grown before the down disappears. In the first plumage young birds are very dark colored, “blackish brown” above and clear uniform, “clove brown” below, but lighter and somewhat mottled on the head and neck. This plumage, which is somewhat glossy on the back when fresh, becomes duller and paler during the fall and winter by wear and fading. Dr. Leonhard Steineger (1885) has made some exhaustive studies of the molts and plumages of this species, based on the examination of fresh material. I can not do better than to quote from his conclusions, as follows:

It will be necessary first to remark that these birds raise two broods during the summer. This is not to be understood as a positive statement that the same parents rear two sets of young every year: although I believe that most of them do: hut simply that I have found the colonies of this species having eggs and downy young at two different times. The first season commencea early In May, the young of this brood being fully fledged in the latter part 01′ July. In the middle of this month, however, the colonies again contained all stages, from fresh eggs to newly-hatched young. During the first days of August I found downy young of almost the same age and still without feathers, while on the 21st of August, 1882, I visited a numerous colony at Poludjoanli, Bering Island, in which the oldest young were about half fledged. These would not be able to fly before the first week of September. Between the two periods, young in all stages of development will be found In the colonies, but proportionately few in number. It will thus he seen that it is safe to assume that the difference in age between the earliest and the latest born young in one year amounts to three months, at least.

We are now prepared to understand that we can find t~vo birds undergoing the corresponding molt at times as much apart as the birthdays of the same two birds. If the first molt occurs, say, ten months after the bird broke the shell, the bird born in the middle of May will molt in the middle of March next year, while the one born in the middle of August will not molt before the middle of June next year. And this conclusion is borne out fully by the observed fads. As will be seen from the details relating to the birds collected by me, as given below, I shot birds in the latter part of February, both younger and older, which were just in the first stage of molting, while, on the other hand, I have a skin before me In full molt from young to adult plumage, as late as July, a discrepancy hardly to be accounted for, except by the above explanation.

When about ten months old, the first plumage, which is of the dark grayish sooty color, wIth some green and purplish reflections in the fresh plumage, changes into the resplendent garb of the adult, from which it then is undistinguishable, except by not having the bright colors of the naked parts of the face and by lacking the white feathers on the neck and thighs. In the following spring, or when about twenty-three months old, it begins to breed.

The above conclusions seem to be substantiated by what material I have examined; I have seen young birds molting into adult plumage in May, June, July, and September, showing that the molt is much prolonged or very variable, probably the latter. Adults have a complete postnuptial molt during the summer and early fall and a partial prenuptial molt in February, March, and April. The highest nuptial plumage, including the white flank patches, the two crests on the head, and the white filaments on the neck and back, is worn during March, April, and May; the white filaments are very brittle and soon disappear; they are seldom seen in museum specimens, as they are easily lost in skinning. The winter plumage is duller or browner than the nuptial and lacks the special adornments mentioned above.

Food: The food of the pelagic cormorant consists principally, perhaps wholly, of fish. Prof. Harold Heath (1915) says: “Several times at sea these birds were seen feeding on herrings.”

It can be distinguished from other species by its size and shape, as well as by the white flank patches, if present. As a tliver and a swimmer it is an expert, though it seldom rests on the water. It must be exceedingly swift in the pursuit of its finny prey. Being more slender and more elegant in form than the other cormorants, the flight of this species is rather more graceful than the others. It is a rakish looking craft in the air with its long, slim neck and long tail, but its flight is not swift; its wing strokes are rather rapid, interrupted by intervals of scaling. Dr. Frank M. Chapman (1902) publishes the following interesting note by Mr. J. D. Figgins on the feeding habits of this species:

When the gulls, by their discordant cries, proclaim the discovery of a school of fish every cormorant Within hearing distance flocks to the scene, and In many cases so thoroughly appropriate the school to their own use that the gulls are compeUed to seek other feeding grounds, as they do not relish diving into a mass of cormorants. The cormorants make no attempt to fish on their own account, but wait until the gulls discover the game and then appropriate it.

Cormorants are usually silent birds and this species is no exception to the rule. Mr. Joseph Dixon (1907) says: “They make a particularly groaning sound when on the nest that sounds like someone moaning in pain. We could hear it quite a ways out before we landed and could not imagine what it was.”

Behavior: These cormorants, which build their nests on inaccessible cliffs, have few enemies to contend with, except the winged robbers of their eggs and young. Mr. George Willett (1912) writes that on St. Lazaria Island:

Owing to the depredations of the crows, very few of these birds succeed in raising an entire brood, and I believe there are many who are unable to raise a single young.. When frightened from the nest, they very foolishly fly a considerable distance to sea and often remain for several minutes at a time. This opportunity is quickly seized by the crows, and in an almost incredibly short time the corniorants’ nest is empty.

Doctor Steineger (1885) refers to a wholesale destruction of this species in the Commander Islands, as follows:

During the winter of 1876: 77 thousands and thousands were destroyed by an apparently epidemic disease, and masses of the dead birds covered the beach all around the islands. During the following summer comparatively few were seen, but of later years their number has again been increasing, thongh people having seen their former multitude think that there is no comparison between the past and the present. Erom Bering Island the reports are similar, with the addition that the stone foxes would not eat the corpses.

Fall: Tbe natives in the vicinity of Bering Sea depend largely on the flesh of these cormorants at certain seasons for food; their skins were formerly used for clothing and their nuptial crests and plumes served as ornaments. Mr. L. M. Turner (1886) writes:

During severe weather of the winter and fall these birds resort to the high rocky ledges or the single rocks which jut from the sea. Some of the rocks are fairly covered with these birds, and these appearing like a lot of black bottles standing on the rock. The natives of all parts of the country use the flesh of this bird for food. Some of the Aleuts, especially those of Attu, prize the flesh more than any other bird. They formerly obtained many of these birds with a kind of net which was thrown over the birds when sitting on the shore rocks, being driven there by the severity of a storm, so that the birds could not remain on the outer rocks without being washed off.

Winter: Mr. W. H. Kobb4 (1900) writing of the winter habits of ihis species near Cape Disappointment, Washington, says:

The violet-green cormorant is only found upon the cape during the winter months, when it is very abundant. It arrives in the fall and departs rather late in the spring. During Its stay upon the cape It associates with the whitecrested cormorant, and the two species may often be seen perched upon the fish-trap poles In large flocks. Both species frequently fly into the fish pots from which they are unable to escape ,since they are unable to fly vertically upward. It is an easy matter for the birds to fly from the poles downward into the square pot formed of netting, but after they once get in they are forced to remain and are generally killed by the fishermen.

DISTRIBUTION
Breeding range: Coasts and islands of Bering Sea and northern Pacific Ocean. From Norton Sound (Sledge Island) and St. Lawrence Island southward along the coast to southern Alaska (Forrester Island) and perhaps farther. Westward throughout the Aleutian Islands and Commander Islands. Southward through the Kurile Islands to Japan (Yezzo). Northward along the Asiatic coast of Bering Sea to northeastern Siberia (East Cape) and westward on the Arctic coast of Siberia to Cape Irkaipij, Cape Kibera Island and Koliutschin Island. Seen in summer and may breed in Kotzebue Sound. Birds breeding near the south end of Vancouver Island are probably referable to resplenden.s. Breeding grounds protected in the following reservations: In Alaska, Bering Sea, Pribilof, Aleutian Islands, St. Lazaria, and Forrester Island.

Winter range: From the Aleutian, Pribilof, and Commander Islands southward throughout the remainder of the breeding range and beyond it south to Puget Sound and to China.

Spring migration: Arrives in northeastern Siberia, Gichiga, as early as May 13, in Norton Sound, Alaska, by June 5, and at St. Lawrence Island, June 2.

Fall migration: Leaves northeastern Siberia about the second week in October and Norton Sound, Alaska, in October or November.

Casual records: Taken at Point Barrow, Alaska, June 8, 1898.

Egg dates: Southern Alaska: Twenty-four records, June 16 to July 31; twelve records, June 29 to July 19. Aleutian Islands: Four records, June 20 to July 4.

BAIRD CORMORANT
PHALACROCORAX PELAGICUS RESPLENDENS Audubon
HABITS

The Baird cormorant is clearly distinct, subspecifically at least, from the northern subspecies of Phalacrocoraei pelagicu.s and it has been suggested that it might be even a distinct species. To what extent the northern and southern forms intergrade and what the limits of the respective breeding ranges are I must leave to others to investigate and decide; but for the purposes of this life history I shall assume that the birds which breed from the coast of Washington southward are resplendens. Much of what I have written about the life history of pelagicus would apply equally well to the smaller southern form, so I will not repeat it.

Nesting: The nesting habits of the Baird cormorant are similar to those of the pelagic, but very different from those of its neighbors on the California coast, the Farallon and Brandt cormorants. The latter two are almost absurdly tame, whereas Baird is very shy about its breeding grounds. The two larger species breed in large colonies and build their nests on the flat tops of the rocky islands or on the broader and more accessible ledges, whereas the slim, little Baird cormorant almost always builds its nest on the narrowest and most inaccessible, little shelves or crannies on the face of some steep, rocky cliff, usually breeding in small scattered groups or singly. The Baird cormorant also uses no sticks in the construction of its nest.

Prof. Lynds Jones (1908) gives the following account of the nesting habits of the Baird cormorant on Carroll Islet, off the coast of Washington:

The nesting places of this cormorant ~vere small ledges or grottoes In precipices. Therefore the most of them were nesting on the ocean side of the island, and at various elevations. Nests were usually placed not nearer together than several feet, possibly because of the character of the rock face. The birds were uniformly more timid than the white-crested. Their single barklike cry was not often heard, even when they were disturbed or frightened.

None of the neets examined contained sticks, but were wholly composed of dry grass, with occasionally a few feathers in the lining, ~~ll of the nest except the outside was clean, but the outside was characteristically covered with lime, end tile rocks below the nest for many feet were white with tIle same substance. In fact, tile nestillg places of these birds could be discerned at considerable distances by the white streaking of the dark gray rocks. All along the coast, when we approached the rocky shores, evidences of these birds were scattered along the rocks.

Mr. Walter E. Bryant (1888), writing of this cormorant on the Farallon Islands, says:

They are less common than the two foregoing species, with which they do not associate. The nests are built usually in the most inaccessible places, and at all altitudes; some were found so close to the water’s edge that they were splashed by the highest waves heating against the rocky shore. The same rookeries are used from year to year, and the same nests are occupied after being robbed, the owners simply adding a few more pieces of weeds before laying. They congregate in colonies of eight or ten pairs, nesting on natural shelves of perpendicular or overhanging rocks. Three or four eggs are laid In a nest of the same material as Is used by the other cormorants. Incubation commences after the first egg is laid, in order to keep it protected from the gulls. The birds lucy be seen on the nests for days before the first egg is laid.

Eggs: The eggs of the Baird cormorant are practically indistinguishable from those of tim pelagic cormorant, though, strangly enough, the eggs, of which I have measurements, average larger. The measurements of 40 eggs, in various collections, average 61.7 by 40.4 millimeters; the eggs showing the four extremes measure 65 by 40 and 51 by 36 millimeters.

Behavior: IReferring to the behavior of Baird cormorants, Mr. W. Leon Dawson (1909) writes:

Cormorants plunge into the wildest waters as fearlessly as sealions, and they carry on their fishing operations about the shoulders of booming reefs, which humans dare not approach. After luncheons, which occur quite frequently in the cormorant day, the birds love to gather on some low-lying reef, just above the reach of the waves, and devote the intervening hours to that most solemn function of life, digestion. There is no evidence that the birds discuss oceanic politics on these occasions; the benevolent assimilation of a twelve-inch cultus cod is presumed to be ample occupation for union hours.

When the birds of a colony quit their nests they launch out swiftly, wagging their head from side to side if the danger is above them. They may join the puffins and gulls for a few rounds of inspection, but oftener they settle in the water at some distance from the shore, a large company of them looking and acting very much like a flock of black geese. It requires quite an effort on the bird’s part to rise from the water, but this is done with a single motion of the wings, unassisted by the feet, as would be the case with heavy ducks and loons. If the shag has been diving it may burst out of the water with the acquired impetus of the chase, and once under way its flight is swift and vigorous and not altogether ungraceful.

Winter: An interesting account of a winter resort of this and other cormorants on an island off the coast of Lower California is given by Mr. A. W. Anthony (1906) as follows:

The first cormorants will arrive at the island as early as 4 o’clock, and taking up their station well back from the beach wiu be joined by the next flock. The black patch on the gray sand extends its outposts until it meets the brown borders of the pelican colony on the one side and the snowy expanse of gulls on the other, completely surrounding them and forcing later arrivals of gulls and pelicans to start other camp grounds farther along. These again are overtaken and surrounded until by dusk the entire side of the island will be one solid mass of closely packed birds, the white of the gulls and brown plumages of the pelicans standing out in striking contrast to the inky blackness of the cormorants, which form over three quarters of the mass. The species all flock separately so far as is possible, and the result is a patchwork of white and gray separated by broad zones of black; even the Brandt and Farallon cormorants roost apart, with the somewhat rare Baird cormorant still further removed, perching on the low cliffs and rocks along the beach. Stragglers arrive until late in the night; the gulls in fact do not all get home until the first of tile early risers begin to leave at daybreak. The departure Is even more gradual if possible than the arrival of the night before, and it is not until the sun is two hours high that the last of the cormorants leave for the fishing grounds.

The following quotation from Mr. C. I. Clay (1911) will illustrate the remarkable diving ability of this species:

~ were one and one-half miles southwest from Trinidad, Humboldt County, California, and about one-half mile off shore. Mr. Francisco had set a net the night before near a blind rock and in twenty fathoms of water. We were taking in the net when a Brandt cormorant came to the surface In Its meshes, then a second one and a third. Although the Baird cormorants were common everywhere on the ocean there were none In the net. On closely questioning the fisherman, he informed me Brandi cormorants were caught almost daily in from five to thirty fathoms of water while using the deep water nets, but were never taken In over forty fathoms of water, while the Baird cormorant (I had taught him the difference between the two species) were often taken In as much as eighty fathoms of water.

I saw several Baird cormorants rise to the surface of the water with pieces of kelp in their bills in places where Joe Informed me the water was over eighty fathoms deep. Brandt cormorants were not seen far offshore, though they were common among the rocks near shore. Is it a superiority in diving or a desire to obtain a certain kind of food that prompts the Baird cormorants to go down deeper than Brandt cormorants while on their feeding grounds?

DISTRIBUTION
Breeding range: Paciflc coast of North America. From extreme southern British Columbia (Sidney Island, near Victoria) southward all along the coast to extreme northern Mexico (Los Coronados Islands). Breeding grounds protected in the following reservations: In Washington, Flattery Rocks, Quillaynte Needles, and Copalis Rock; in Oregon, Three Arch Rocks; and in California, Farallon.

Winter range: Includes most, if not all, of the breeding range and extends southward to, at least, the central Mexican coast (Cape San Lucas and Mazatlan).

Egg dates: California: Sixty records, May 3 to July 15; thirty records, May 29 to June 19. Los Coronados Islands: Thirty records, April 17. Washington and Oregon: Seven records, June 10 to 21.