Brandt’s Cormorant

The Brandt’s Cormorant is blackish in color with a tan throat patch (non-breeding), a long, skinny neck, and a fairly long bill. Throat pouch bright blue in breeding plumage.

Sexes similar.

Blue throat patch is only present during the breeding season.

Juveniles are brownish in color.

Oceans and coastlines.

Fish and shrimp.

Photograph © Greg Lavaty.

Forages by diving underwater.

Resident along much of the west coast of North America. Populations stable.

More information:

Bent Life History

Visit the Bent Life History for extensive additional information on the Brandt’s Cormorant.

Wing Shape

The shape of a bird’s wing is often an indication of its habits and behavior. Fast flying birds have long, pointed wings. Soaring birds have long, broad wings. Different songbirds will have a slightly different wing shape. Some species look so much alike (Empidonax flycatchers) that scientists sometimes use the length of specific feathers to confirm a species’ identification.

• Female, immature, Washington, Jan.
• From below

Wing images from the University of Puget Sound, Slater Museum of Natural History

Brandt’s Cormorants occur nowhere but North America.

Brandt’s Cormorants have a high proportion of blood compared to their body size, which likely aids in diving ability.

A few croaks may be given on the breeding grounds.

The nest is a mound of marine plants and droppings placed on the ground.

Number: 4.
Color: White or bluish.

Incubation and fledging:
– Young hatch at 28-32 days.
– Young fledge (leave the nest) about 25-40 days after hatching.

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 Brandt’s Cormorant – the common name and sub-species reflect the nomenclature in use at the time the description was written.

This large, heavy, well-marked species is perhaps the best known, the most abundant, and the most characteristic cormorant of our Pacific coast, being found in all suitable localities from southern Alaska to Lower California. It is mainly a resident throughout its range, where its heavy, lumbering form is a familiar figure on the coast at all seasons, sitting for hours on any convenient perch over the water in lazy indolence, congregating in large numbers in its favorite roosting places on outlying rocks or gathering in great black rafts on the water where fishing conditions are favorable.

Nesting: For breeding purposes it congregates into large colonies on rocky islands or on the more inaccessible rocky cliffs of the mainland, where it is beyond the reach of marauding enemies, except its most persistent and most successful foe, the western gull. While cruising among the Santa Barbara Islands we found many a large breeding colony of Brandt cormorants, visible many miles distant as a conspicuous, whitewashed space on some prominent rocky slope or promontory; as we drew near we could see that the white surface was dotted with hundreds of black specks, which later we could recognize as cormorants sitting on their nests, spread closely and evenly over the gently sloping rocks.

Brandt cormorants seem to prefer to nest on the flat top of a rocky island, on a gradually sloping incline or more often stilL on a high rounding shoulder of rock. They never seem to nest on the inaccessible perpendicular cliffs, such as are chosen by the Baird cormorants. The nests seem to be easily accessible and they are so, provided one can make a landing on the island, but this is generally not so easy, for these rounding shoulders of rock often terminate iii steep and slippery sides washed by dangerous breakers. The nests are not very different from those of the Farallon cormorant, except that they never use sticks in their construction, which the other species usually does utilize. But the birds themselves are much shyer and can be easily recognized by the blue gular pouch, which is very conspicuous during the breeding season. The nest is made of various seaweeds and sea mosses, which the birds may be seen gathering by diving in the vicinity of their breeding grounds; the nest is used for successive seasons, fresh material being added each spring to the foundation of rotted debris and guano; they are often placed so near together that there is barely walking space between them.

Two interesting colonies of Brandt cormorants, near Monterey, California, are described by Prof. Leverett M. Loomis (1895) from whom I quote in part as follows:

Two rookeries were discovered; one at Point Carmel and the other at Seal Rocks. June 25th I visited the former, which is situated on a rock or little Islet in the ocean at the extremity of Point Carmel, about fifteen yards from the mainland. This rock rises perpendicularly some forty or more feet above the water. At first sight it does not seem that it can be scaled, but close;~ inspection reveals that a foothold may he had in the seams and protuberances on its water-worn sides. Only on days when the sea is very calm can the rock be landed upon, and then only from the sheltered channel separating it from the mainland. Fortunately, it happened that the sea was quiet the day of my visit. The following day a party of Stanford University students were unahie to land on account of the heavy surf.

We first took a view of the rookery from the mainland. The cormorants were very tame, remaining on their nests while we clambered down the sloping rocks and while we stood watching then] on the same level only a few yards away. They ~vore safe, however, from its precipitous walls of rock, effectually cutting oft further advance. They were equally tame when the hoat drew near as we approached from the water.

The clefts in the sides of the rock were occupied by Baird cormorants and the top by Brandt’s. There were comparatively few of the former, hut of the Brandt cormorants there ;vere upwards of two hundred pairs. Their nests covered the top of the rock, every available situation being occupied. The surface was so uneven that all the nests could not be seen from one spot. Standing in ono place I counted one hundred and eighteen.

All the nests of the Branit cormorants on the rock contained eggs (apparently in an advanced state of incubation), with the exception of eleven, which had young birds in them. In ten, the young were just out of the shell. In the remaining one they were as large as “spring chickens..” The eggs In seventyseven nests were counted by a companion. Twenty-one contained four eggs each; thirty-six, three eggs; fourteen, two eggs; three, five eggs; three, one egg. The most frequent numbers were therefore three and four, probably the ordinary clutches.

Sardines were lying In little hunches near the nests, apparently placed there as food for the birds that were setting.

The smell from the accumulated excrement was sickening. The sides of the rock were so daubed that It appeared to be white toward the top. Flies swarmed about the rookery.

It was not until I fired my gun that the brooding birds began to desert their eggs. The Baird cormorants were the first to go. Many of the Brandt cormorants lingered on the edge of the rock while I walked about among the nests, only a few steps away. Finally all were driven to the water, where they formed a great raft. They began to return as soon as I left the top of the rock.

The rookery at Seal Rocks was much larger than the one at Point Carmel. The rocky Islet upon which it was located is considerably greater In size and much lower in elevation than the Point Carmel islet. From the mainland, less than a hundred yards distant, no nests were in sight, all being on the side toward the ocean, hidden from view by a sort of dividing ridge. The Del Monte drive passes along the shore directly opposite the Rocks. It Is a much frequented roadway, and the summer visitors have greatly persecuted the birds with firearms, forcing them to seek shelter for their nests behind the projecting rock.

My first visit to the rookery was made July 2d. As at Point Carmel, a landing could be effected only on the shore side of the IsleL The resident population was composed exclusively of Brandt cormorants. Their nests were crowded so closely together on the uneven surface of the rock that room to place the foot was not always readily found. Some of the nests were on little points of rock, others in crevices, every available spot being utilized. Most of the eggs had batched. The young were in different stages of growth, varying In size from those just out of the shell to half-grown ones. The larger left the nests when approached, and huddled together on the edge of the Islet well above the reach of the surf. There was such a complete mixing up of babies that the old birds must have had some trouble In sorting them out when they returned, for Immediately after I landed most of the adults retreated to the water, congregating In a great raft a short distance away. A few of the bolder remained behind for awhile. Several, apparently females, kept close by their young until I approached within ten feet of them, when their courage failed and they took flight, leaving the young to shift for themselves. Txvo of the larger young birds sought refuge on an outlying rock, separated from the islet by a little channel. They had apparently never been In the ivater before. They succeeded, nevertheless, In swimming across the chnnnel and climbing up the steep sides of the rock, although a number of times they were buried out of sight by Incoming waves.

A vibratory movement of the gular sac, apparently occasioned by fear, was noticed In a number of adults and half-grown young. Most of the adults observed on the rookery appeared to have lost the nuptial filaments.

The general form of tIme nests was circular, except where wedged In between rocks. They appeared to be constructed entirely of eel grass (Zostermm). Those containing the larger young were trampled down. Two typical, untrampled nests yielded the following niensurements: Outer diameter 22 by 19, inner diameter 10 by 10, depth 4 by 4, height Sj by 7.

Not many fish were lying about the nests. There were too many hungry mouths to be filled for a store to accumulate as at Point Cannel rookery. It was evident that sanitary measures were not in vogue, for the decaying bodies of several birds were suffered to remain and add to the almost intolerable stench of the excrement deposits. Quantities of feathers were scattered about and there were myriads of flies. Some of the flies accompanied us in the boat most of the way to Point Pines, much to our annoyance.

Referring to this species on the Farallon Islands, Mr. Milton S. Ray (1904) writes:

Bandt cormorant is the commonest and biggest species of the island cormorants. Besides the large rookery en the more gradual slopes on the north side below Main Top Ridge, extending from near the water to well up the hillside, there are large colonies nesting on Saddle Itock and Sugar Loaf. ~Ve gained our first view of the rookery on West End when we crossed the ridge on the morning of May 30. Right below us, with scarcely foot-space betxveen the nests, was the great city of cormorants. I counted 156 nests; on June 3 they had increased to 187, and they xvere still building. The weeds that trail over the rocks form most of the nest material, and these become more or less dry by the end of May and are easily detached by the birds; in fact a strong wind will frequently rip up a whole mat like bed. In make and size the nests of this species are like those of the preceding. I noticed considerable sea moss among the nest material, which is undoubtedly uprooted by the birds themselves, but it was not in such variety as I had been led to believe. Quarrels over nest material were of frequent occurrence among the birds of the rookery, but the most arrant robbers came from the settlement on Sugar Loaf, where the weeds do not grow. It was a queer sight to see one of these great lumbering-flighted cormorants come flapping into the colony, and after some opposition succeed and go awkwardly sailing off with a long stringing bunch of weeds.

All day long the great rookery was a scene of activity; everywhere the ponderous clumsy birds, using to the best of their ability what skill nature had endowed them with, were fashioning their weed-homes, whfie scores of setting birds ever and anon would rise to stretch their stiffened wings or to greet their mates returning fish-laden from the sea.

Eggs: The Brandt cormorant lays from three to six eggs, usually four, and only one brood is raised in a season. The eggs are not distinguishable from those of other cormorants of similar size. The ground color is pale blue or bluish white, which is more or less completely concealed by a white calcareous coating, which becomes very much soiled during the process of incubation. The shape varies from “elongate ovate” to “cylindrical ovate.” The measurements of 41 eggs, in the National Museum and the writer’s collections, average 62.2 by 38.6 millimeters; the eggs showing the four extremes measure 68.5 by 39.5, 68 by 40.5, 56 by 39, and 61 by 36 millimeters.

Plumages: The young cormorant, when first hatched, is blind and naked, an unattractive object covered with greasy black skin. The down soon appears, however, and before the young bird is half grown it is completely covered; the down coat is “clove brown” above, slightly paier below, mottled with white on the under parts and wlngs. The feathers of the wings and tail appears first and are fully developed before the body plumage m acquired; the doxvn disappears last on the head and neck, after tile young bird is fully grown. The brown plumage of the first winter succeeds the downy stage and is worn for nearly a year, fading out to a very light color on the breast in the spring. There is a partial molt during the first spring, but no very decided advance toward maturity is made until the first complete molt the following summer. At this first postnuptial molt a plumage is acquired which is somewhat like the adult, but there is still much brown mottling in the head, neck, and under parts. During the following spring there is still further advance, the nuptial plumes are partially acquired and the young bird is ready to breed; but the fully adult nuptial plumage is not acquired, I believe, until the next, the third, spring. The partial prenuptial molt of adults, at which the long nuptial plumes of the neck and back are acquired, occurs in February and March; and the complete postnuptial molt extends from August to October. Both old and young birds in any plumage can be distinguished from the Farallon corniorant by the outline of the feathered tract bordering the gular sac; in the Brandt cormorant tile gular sac is invaded by a pointed extension of the feathered throat~ area, ~~llereas ill the Farallon the gular sac has a broad, rounded outline.

Food: Like other cormorants, this species feeds almost exclusively on fish, which it obtains by diving. As it is a maritime species, it lives on salt-water fishes, many of which it obtains near the bottom and often at considerable depths. Professor Loomis (1895) took some fish from the gullets of these cormorants which were identified as “a species of rock cod (Sebastocle8 paucispinis) .’~ He also says: ” Great rafts of these cormorants collected on the bay whenever ‘the feed came in.’ At a distance these gatherings present a very peculiar appearance. The water seems to be thickly set with black sticks, often covering an area of several acres.”

Mr. A. B. Holvell writes me:

The throat is capable of great expansion. I have seen an adult down a fish, after repeated attempts, which seemed surprisingly large for the size of the bird. They forage lo very deep water. I have seen tiiero briug up seaweed where I was assured that there was none to be lied within a 150 feet of the surf ace.

Behavior: Mr. Dawson (1909) says:

It is a familiar figure on tile stringers of salmon traps, as well as on isolated piles or the old abandonetl wharves on the lower Sound. If the bird is not exactly of a mind to fly at the first alarm from the passing steamer, it stands with wings half open, that, should necessity arise, no time may be lost in making good its escape. Again, a group of them will sit on a low-lying reef, or even on a floating log, with wings half extended, “drying their clothes” in the sunshine. The wings as well as the feet are used under water, but we can not guess why the cormorants more than other aquatic species should be averse to wet plumage.

The chief enemy of the Brandt cormorant in its breeding grounds is that persistent robber of all the sea birds on the California coast, the western gull. The cormorant is big and strong enough to defend its eggs and young against its weaker foe, but the omnipresent gulls are so numerous, so persistent, so active, and so ever on the alert to seize a favorable opportunity, that a brood of young cormorants is successfully raised only at the price of eternal vigilance. Fortunately the cormorants are prolific layers and persevering in their attempts to raise a brood, for the stupid birds are so often driven away from their nests by some chance intruder that the active gulls, which are not so easily frightened, clean out all the eggs in a colony so frequently that it is a wonder that the cormorants are not discouraged and exterminated.

The cormorants are harmless and peaceable neighbors among the various species which share their breeding grounds: murres, gulls, pelicans, and other cormorants. At other seasons of the year they also associate with other species. Mr. Loomis (1895) says:

Sometimes solitary cormorants returning to their rookery Joined the flies of migrating California murres, and frequently single murres were observed bringing up the rear of strings of outgoing cormorants. On one occasion a Callfornia brown pelican was seen at the end of a line of cormorants.

Winter: In their winter resorts they often congregate in enormous rookeries or roosts. They winter as far north as Puget Sound and are common southward all along the coast in winter. A long line, or a V-shaped flock, of great, black birds winging their heavy flight to and from their feeding grounds is a familiar sight about the islands and the rocky bays.

DISTRIBUTION
Breeding range: Pacific coast of North America. From southern Alaska (Forrester Island) southward all along the coast to southern Lower California (Magdalena Bay). Breeding grounds protected in the following reservations: In Alaska, Forrester Island; in Washington, Flattery Rocks and Quillayute Needles; in Oregon, Three Arch Rocks; and in California, Farallon.

Winter range: Includes most of the breeding range, extending from northern Washington (Puget Sound) to southern Lower California (Cape San Lucas).

Egg dates: California: Fifty-eight records, April 3 to July 15; twenty-nine records, May 28 to June 20. Lower California: Four records, March 28 to April 23.