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Northern Gannet

These large seabirds are known for their big build and massive wingspan.

Breeding in dense colonies on steep marine cliffs in only a handful of locations off eastern Canada, the Northern Gannet occurs along much of the Atlantic and Gulf Coasts during winter. Lacking the brood patches used by most birds for incubation, Northern Gannets instead use their feet, which have an unusually dense network of blood vessels to aid in the transfer of heat to the sole egg.

Northern Gannets don’t typically breed until age three, four, or five. With a single egg per clutch and a late start to their breeding life, they typically have long lives to make up for these limitations. The oldest known Northern Gannet in the wild lived over 21 years.

 

Description of the Northern Gannet

BREEDING MALE

Northern Gannet

Photograph © Glenn Bartley

The Northern Gannet is a large, long-winged seabird with a white body, black wingtips, and a yellowish head.

Female

Sexes similar.

Seasonal change in appearance

None.

Juvenile

Juveniles are dark gray.

Habitat

Oceans and sea cliffs.

Diet

Fish.

Northern Gannet

Photograph © Glenn Bartley

Behavior

Forages by plunging into the water from the air, or by swimming.

Range

Breeds off the northeastern coast of Canada as well as in Europe. Winters offshore along the East and Gulf Coasts of the U.S.

Fun Facts

When 2 months old, gannet chicks can weight 50 percent more than adults.

Gannets bathe by thrashing around on the surface of the water.

Vocalizations

A variety of harsh calls and croaks are given.

 

Similar Species

  • Boobies have dark rather than white secondaries.

Nesting

The nest is a pile of plant material on the ground or a ledge.

Number: 1.
Color: Pale blue.

Incubation and fledging:  
– Young hatch at 42-46 days.
– Young fledge (leave the nest) in 84-97 days after hatching.

 

Bent Life History of the Northern Gannet

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 Northern Gannet – the common name and sub-species reflect the nomenclature in use at the time the description was written.

GANNET
MORUS BASSANUS (Linnaeus)
HABITS

Day after day we had gazed, from the hilltops of the northern Magdalens, across the waters of the stormy Gulf of St. Lawrence toward the distant Labrador coast, where we could see looming up on the horizon a lofty reddish mass of rock, the goal of our ambitions and the mecca of many an American ornithologist, Bird Rock. At last the day came sufficiently smooth for us to risk the trip in our tiny craft, the only boat available. To visit and storm that almost impregnable seabirds’ fortress is risky enough in a seaworthy vessel, for storms come up without much warning and the waves thunder at the base of its almost perpendicular cliffs with such fury, that only during the calmest weather can a landing be effected with safety on a narrow beach. At the time of our visit the present comfortable landing had not been completed. It is now no longer necessary to be hoisted up in a crate, a hundred feet or more to the top of the rock.

Gannets were seen flying past us toward the rock, as they returned from their fishing grounds and as we drew near we could see a swarm of white birds circling about it. The setting sun shone full upon Its towering cliffs of red sandstone, deeply cut or carved by the elements into ledges and shelves, of varying sizes and shapes; the broader ledges seemed covered with snow and it was hard to believe that such wide bands of white were really colonies of nesting gannets. The whole side of the rock seemed to be covered with birds; wherever there was room for them the gannets were sitting on their nests on the wider ledges; clouds of noisy kittiwakes were hovering overhead or nesting on the smallest shelves of rock; ra.or-billed auks were breeding in the crevices near the top of the rock and the murres, Brunnich, and the common, were sitting in long rows upon their eggs on the narrower ledges. Such was the home of the gannet as I saw it in 1904.

The history of the gannet colonies of Bird Rock is interesting as showing the effect of human agencies in the extermination of bird life. It begins with Jacques Cartier’s account of his voyage to Canada in 1534, at which time there were apparently three islands in the group, of which he says, according to Gurney’s (1913) rendering of Hakluyt’s translation: “These ilands were as full of birds as any medow is of grasse, which there do make their nestes; and in the greatest of them there was a great and infinite number of those that wee cal margaulx, that are white and bigger than any geese.” There is very little doubt that the birds he referred to were gannets. For three centuries the persecution of these birds was not sufficiently severe to reduce materially their numbers, for when Audubon (1897) visited Bird Rock in 1833 it was a most wonderful sight, as the following graphic description, taken from his journal for June 14, 1833, well illustrates:

About ten a speck rose on the horizon which I was told was the rock. We sailed well, the breeze increased Last, and we neared this object apace. At eleven I could distinguish its top plainly from the deck, and thought it covered with snow to the depth of several feet; this appearance existed on every portion of the flat, projecting shelves. Godwin said, with the coolness of a man who had visited this rock for ten successive seasons, that what we saw was not snow, but gannets. I rubbed my eyes, took my spyglass, and in an instant the strangest picture stood before me. They were birds we saw: a mass of birds of such a size as I never before cast my eyes on. The whole of my party stood astounded and amazed, and all came to the conclusion that such a sight was of itself sufficient to invite anyone to come across the gulf to view it at this season. The nearer we approached the greater our surprise at the enormous number of these birds, all calmly seated on their eggs or newly hatched brood, their heads all turned to windward and toward us. The air al~ve for a hundred yards, and for some distance around the whole rock, was filled with gannets on the wing, which, from our position, made it appear as if a heavy fall of snow was directly above us.

At that time the whole top of the rock was covered with their nests and it was regularly visited by the fishermen of that vicinity, who killed the gannets in large quantities for codfish bait. The stupid birds were beaten down with clubs as they tumbled over each other in their attempts to escape. Sometimes as many as 540 of them have been killed by half a dozen men in an hour, and as many as 40 fishing boats ~vere supplied regularly with bait each season in this way, the birds being roughly skinned and the flesh cut off in chunks.

When Dr. Henry Bryant visited Bird Rock on June 23, 1860, the colonies were very much reduced in numbers, although the lighthouse had not been built at that time and the gannets were nesting over all of the northern half of the flat top of the rock. He estimated that there were at least 100,000 birds in this colony and about 50,000 that were nesting on the side of the rock. Mr. C. J. Maynard visited the rock in 1872, three years after the lighthouse was built, and found the colony on the summit reduced to 5,000 birds. In 1881 Mr. William Brewster reported only 50 pairs still nesting on the flat top of the rock, and since that time they have abandoned it entirely, resorting only to the safer locations on the ledges. In 1881 the total number of gannets nesting on Bird Rock was estimated at 10,000, and at the time of our visit in 1904 we estimated that their numbers had been reduced to less than 3,000 birds. Fortunately, they are now protected by the lighthouse keeper, and will probably not be further reduced in numbers by persecution on their breeding grounds, but the soft sandstone cliffs of Bird Rock are gradually wearing away and it is only a question of time when their old home will disappear, and it is doubtful if they can find another suitable and safe substitute for it.

Though not so well known as Bird Rock, the island of Bonaventure, off the Gasp Peninsula in the Gulf of St. Lawrence, is fully as important as a breeding resort for gannets, for it contains by far the largest colony of these birds on the American coast. Gurney (1913) records this colony as containing about 7,000 gannets. It has a similar formation of red sandstone cliffs some 300 feet high and may, at some remote period in the past, have formed a part of a chain of cliffs or islands of which Bird Rock is now the surviving outpost. There are many broad ledges on Bonaventure Island which are practically inaccessible, offering attractive nesting sites for thousands of gannets, where for many years to come they will be safe from molestation. Gannets are said to have nested on Funk Island many years ago, but after the extermination of the great auk the gannets probably shared a similar fate. Another colony of recent existence was on Perroquet Island, of the Mingan group, off the south coast of Labrador. Mr. William Brewster noted several hundred birds there in 1881, but they disappeared soon after that. ‘We saw a few gannets flying about these islands in June, 1909, but were told that they were not breeding there, having been driven away by constant persecution. Bird Rock and Bonaventure have both been set apart as reservations by the Canadian Government. where these birds will be permanently protected.

Spring: The northward migration of the gannets begins in April and extends well into May, following the earliest movement of herring and other fish on which it feeds. They arrive on their breeding grounds in the Gulf of St. Lawrence in May, many of the older birds being already paired. Love making and nest building begin at once and eggs are laid late in May or in June.

Courtship: I have never seen the courtship of the gannet, but Dr. Charles W. Townsend has sent me the following interesting notes on what he calls the courtship dance, although, at the time of his observations, the breeding season was well advanced. He says:

I spent many hours in the summer of 1919 under most favorable conditions near the great gannet nesting ledges on the cliffs of Bonaveuture Island; I saw tile dance repeated by hundreds of pairs ninny times and I came to the same conclusion that Professor Fisher did in the case of the Laysan albatross, namely, that it was originally a courtship dance and that It was continued from habit and from the joy of it, in the same way that the song sparrow continues to sing long after the nesting season.

Let me describe a typical performance: As the sexes are alike in plumage, they can not be distinguished apart. One of them: we will assume it is the male: is swinging around In great circles on rigidly outstretched and motionless wings. He passes within a few yards of me and swings toward a shelf crowded with birds brooding their downy black-faced young. Alighting on the edge, he elbows his way along the shelf, notwithstanding the angry looks, the black mouths suddenly opened, and the vicious pecks of his neighbors. All of these he returns in kind. Arrived at the nest, he Is enthusiastically greeted by his mate, who, disregarding the young bird beneath her, rises up to do her part In the dance. The birds stand face to face, the wings slightly raised and opened, the tail elevated and spread. They bow towards each other, then raise their heads and wave their bills as If they were whetting these powerful Instruments, or as if they were performing the polite preliminaries of a fencing bout. From time to time this process is interrupted as they bow to each other and appear to caress each other as each dips Its pale-blue bill and cream colored head first to one side and then to the other of its mate’s snowy breast. With unabated enthusiasm and ardor the various actions of this curious and loving dance are repeated again and again, and often continue for several minutes. After the dance the pair preen themselves and each other, or the one first at the nest files away, and the new arrival waddles around so as to get back of the nestling, and the strange process of feeding takes place.

This dance is not only performed by pairs, as first described, hut not infrequently individuals perform a passcul; it may be because he or she is wearied with waiting for its mate. The wings are slightly raised and opened, the tail elevated and spread, the bill pointed vertically upwards and waved aloft, thea dipped to one side under the half-open wing and then to the other, the bill raised and waved again, and so on over and over again. Owing to the great volume of sound from the ledges, it is impossible to distinguish any individual performer, and I was unable to tell at what point In the dance and to what extent the song was Important. The sound is like that of a thousand rattling looms in a great factory, a rough, vibrating, pulsing sound: ” car-ra, car-re, car-re.”

Nesting: An account of the nesting conditions as we saw them on Bird Rock and on North Bird Rock, will serve to illustrate the two common methods of nesting, which are also typical of the species elsewhere. On Bird Rock the nests were all on the ledges on the sides of the rock; the broader ledges were well covered with nests several rows deep, and many smaller shelves were occupied by as many nests as they could hold. The nests varied greatly in size and in style of construction from practically nothing to well-made nests 18 inches in diameter and 5 inches high; probably the nests are added to from year to year by more or less extensive repairs, so that the oldest nests become quite bulky. As a rule, they were fairly well made of fresh seaweed, kelp, or rockweed, in many cases still wet, as if recently pulled up by the birds, but more often partially dried. There were usually a few straws and feathers in or about the nests, and in one case a large piece of canoe-birch bark had been bro.ught in, probably as an ornament. The nests at that date, June 24, all contained eggs, a single egg to each nest, and some of the young had hatched. There was always more or less filth about the nests, broken eggs, decaying fish, and excrement, the ledges often being whitewashed with the latter.

We found primitive conditions still prevailing on North Bird Rock, about three-quarters of a mile from the large rock; this had been cut into three parts by the action of the sea, two flat-topped rocks with perpendicular sides, joined by a rocky beach and an inacces sinble pillar of rock separated by water. We climbed up the steep sides of one of the rocks and as we looked over the top of the cliff we saw, in miniature, what might have been seen on Bird Rock 50 years ago, a wildly scrambling mass of great white birds, frightened by our sudden appearance and stumbling over each other in their haste to get away. The whole flat top of the rock was covered with their nests, set about 3 feet apart, leaving just room enough to walk among them, and sufficiently separated for each sitting bird to be beyond the reach of its nearest neighbors, a necessary precaution, for gannets are quarrelsome birds ond frequently steal the nesting material from neighboring nests. These nests had evidently been occupied year after year for many seasons, new material being added each year, until a considerable pile of soil had been accumulated by the gradual decay of the nest material and the new portion of the nest occupied only the top of the mound. The nests, described by the earlier writers, on the flat top of Bird Rock showed similar signs of age. Gurney (1913) gives an interesting list of the miscel laneous articles that have been found in gannets’ nests and says of their increasing bulk: “Gannets’ nests have ever been regarded as substantial edifices: although only intended to receive one egg: in truth, their size attracted attention centuries ago, when in a fissure, or leaning against the rock; Mr. J. M. Campbell has obliged me with a photograph of one 5 feet in height, but they are not all equally large, and some do not measure 18 inches across.”

Eggs: The gannet lays only one egg, which is not large for a bird of its size, varying in shape from elongate ovate to elliptical ovate. The pale bluish white ground color is almost wholly con cealed by a thick calcareous deposit, which is dull white at first but soon becomes nest stained and much soiled by mud and dirt from the birds’ feet. I :

The measurements of 44 eggs, in various collections, average 77.0 by 47 millimeters; the eggs showing the four extremes measure 86.5 by 53.5, 70 by 47, and 80 by 37 millimeters.

The period of incubation is variously given by different observers as from 39 to 44 days, and, as Mr. Gurney (1913) suggests, probably 42 days is about the average. Both sexes incubate. The absence of any bare hatching space on the belly of the gannet is due to the peculiar method in which the bird incubates. Mr. J. M. Campbell, of the Bass Lighthouse, has given a very good account of this, which Mr. Gurney (1913) quotes, as follows:

Alighting on the edge of the nest, tbe bird shulhies oji to the sballow depression, carefully adjusting the huge webs of 1)0th feet over the egg until it is completely concealed from view. The body is then lowered over tim feet until tim breast featbers but barely cover them, giving one the ixnpre~ion that the bird is not sitting sufficiently far forward on the nest. From this habit the eggs, originally chalky white, soon become stained and discolored.

Young: The following account of the hatching process is also taken from the writings of the same excellent observer:

On the 5th of June the young solan was seen emerging from tile shell * * * The young bird, on making its exit from the egg, appeared to use at first tile little horny excrescence on the tip of the upper inaudible for the purpose of rupturing the inner membrane, under pressure being afterwards sufficient to chip the shell. This is invariably effected at tile broad end, a little deeper than cue would cut a breakfast egg. The chipping was continued slowly, bit by bit; first a small portion of the tough membrane was ripped, then the opposing shell pressed out. After a short rest, tile bird wriggled a little farther round: the bill always in view and again renewed tile attack, until fully two-thirds of the circumference had been cut. Tile claws of one of tile feet now made their appearance over the lower edge of the fracture, and, by dint of pressure of the whole body, the remaining third of the shell was snapped, and out tumbled a black, sprawling object, helpless, blind, bare as the palm of one’s hand, and whining like a puppy dog.

The very young gannet when first hatched is naked and livid gray in color, an unattractive object, fat, shapeless, and helpless. It is carefully brooded by its devoted parent, for it must be shielded from the hot sun and protected against the rain and cold fogs until, in the Course of about three weeks, its protective coat of soft, white down completely covers the body. It is well fed by semidigested food front its parents’ crop and increases rapidly in size, until it equals or even exceeds the adult bird in weight. When feeding a very young bird, tile parent practically scoops the little fellow into her mouth, but when larger the youngster is able to dive into the cavernous throat and fish for himself. When old enough to eat solid food the young bird is fed on fresh fish deposited near the nest by its parents. When about six weeks old the plunge appears and by the end of September the flight stage is reached. Concerning this interesting and critical period in the life of the young gannet, I can not do better than quote what Mr. Gurney (1913) has to say about it, as follows:

When the young gannets are twelve or thirteen weeks old, instinct tells their parents that they are quite fat enough for their own good, and that any more stuffing with fish will make them too unwielding to fly. Accordingly it would seem that they desist from feeding their young for the last ten days before they quit the ledges. As a matter of fact, It must be an exceedingly necessary pre. caution, for if too heavy, the young gannet, when it launches itself for the first time Into space, would often not g?t clear of the rocks. When the day comes for the mighty plunge to be made, spreading wide their great sails of wings, the young gannets may be seen to half fly, half fail, into the abyss below. This does not take place until the month of September has commenced, and then numbers of them are to he seen quitting the safety of their ledges. A singular, not to say absurd sight, it is to stand, as my son and I did, on the Bass Rock and watch their awkwardness and hesitation, like that of a timid human bather about to take a first header into the water. I reckoned, when I was there In 1906, that between August the 29th and September the 4th, two hundred and fifty young gannets made the plunge, and with It took their departure from the Bass Rock.

For some days before their actual departure the young gannets may be seen continually flapping their long black wings, which is done, it is to he presumed, to relax the joints and strengthen the ligaments; ten or twelve young gannets may be viewed going through this performance at the same time on the ledges. Notwithstanding so much preparation, some make a bad start, and I was told at Ailsa Craig, where there Is a belt of rock-strewn shore to be crossed, that they not infrequently fall on to it. In squally weather others lose their balance and are carried by a gust of wind down Into the sea before they are ready. But even if they do meet with either of these mishaps, they are not necessarily left to die, for old ones: very likely not their own parents: will sometimes provide for them.

The flight, or, rather, descent, of the young gannet from its natal ledge is a very unsteady performance, yet on the whole it is well sustained, so that the bird has probably achieved a distance of half a mile before the final descending curve into the sea takes place, which ends with a mighty splash caused by impact with the water. The otopyn, or natural effection, of which Gilbert White wrote so eloquently, Is now past and over, and the young one must shift for itself as best It can In the world of waters. When once launched, the young gannet is comparatively safe, except that it is now in some measure at the mercy of the tide. In the sea It remains, drifting hither and thither for the space of two or three weeks. It is apparently unable to rise from the water, and all evidence points to its receiving no food whatever except the sustenance contained in its own subcutaneous layer of grease, which is considerable enough to impart nutriment to the rest of the body. Besides tide, it has to reckon with any high wind, but September Is generally a tranquil time of the year and young gannets from Ailsa or the Bass soon work their way out to sea.

Having reached the sea, we shall be safe in assuming that the young gannet will be nearly four months old before it voluntarily essays a second flight. Even this Is much less than is the case with the young albatross. Then a new phase of Its life begins; It rises from the water with a newly found power, henceforth to find Its own livelihood by those beautiful plunges which are the admiration of all who see them.

Plumages: The naked young gannet, even when first hatched, shows some signs of sprouting down, and when about 10 days old it is completely covered with long white down, except on the face, which remains naked and black. When about 3 weeks old the tail and wing quills begin to sprout, followed by the black juvenal plumage of the scapulars and back, and the full first plumage is assumed at an age of 9 or 10 weeks. This is the plumage in which we see the young birds in the fall, nearly black above, sprinkled with small triangular spots of white, one on each feather, and much lighter below, where the feathers are largely white. During the first winter and spring a gradual change takes place, by fading, wear, molt, and growth of new feathers. Mr. Gurney (1913) has described this very well from observations made on a captive bird. He writes:

At what I considered to be four months old the white spots upon this young gannet were less numerous and were becoming distinctly smaller, being presumably worn by abrasion. At five months its entire plumage had grown darker. At six months there was not any further change worth registering; nor at seven months. At eight months all its feathers were darker, and the molt had set in, shed feathers being pretty numerous in its enclosure. At nine months its new tail-feathers were growing: very large and very stiff when compared with the limp rectrices which they replaced. At the same time new feathers were discoverable upon the back, and these were black with small white spots on the tips of a few only. Some white color was apparent at the back of the neck also. At ten months the white on the neck had spread and was beginning to cover the throat and breast, and at eleven months the whole of the underparts were white.

Describing the plumage of the second year, he goes on to say that when 12 months old its forehead retained: Many dark speckles, but there were no longer many spots of white to be seen on the back. By the time it had reached 16 months there was not a spot of white on my young gannet’s back, which was nearly black, but two-thirds of its head and neck were now quite white. Although the molt seemed to be finished, It was evident that there was still some change of color going on, either by fading or abrasion. The only part of its body which remained in the spotted plumage now was the lower part of the belly. At 17 months the head and neck were nearly xvhite. At 21 months the lesser upper wing coverts and a part of the scapulars were white also, and three white spots of some size were visible on the hack. At 22 months a shade of yellow came out on the head and neck. At 23 the white spots or blotches on the back were the size of a form, and several new ones had appeared upon the wing coverts. At 24 the blotches were still larger, and at 25 months the bird, which had been in excellent health until the last fortnight of Its life, unfortunately began to droop and died: August 7th, 1908: and my observations came to an abrupt end.

When a gannet is about 26 months old It exhibits a yellow occiput and a partly black back, forming a handsome conjunction of colors. When 28 months It should have, If the normal molt has been adhered to, nearly acquired Its complete white plumage, but there still remain a few small patches of black on the lower part of the back and upon the wings. The black tall is the last portion of the immature plumage to be shed; in a molt which is normal, the two middle rectrices, which are the longest of the twelve, being the final ones to go.

I have examined a large number of young gannets in first and second year plumages (I have a series of 26 immature birds in my own collection), all of which agree substantially with Mr. Gurney’s observations. During the first year young gannets are extensively mottled on the under parts, with an increasing amount of white in heads, necks, and under parts toward spring; the upper parts are slate colored with a hastate spot of white at the tip of each feather. These slate-colored feathers with the white spots are characteristic of the first-year plumage; but they are renewed on the back, rump, and lesser wing coverts at the first complete molt, when the bird is about a year old, so that they appear also during the first part of the second year; however, the white tips disappear by wear during the fall, and before winter the young bird has a solid black back. A few white feathers appear in the lesser wing coverts at about this time.

During the second winter, then, the young gannet has a solid black back in which an increasini~ number of white feathers appear toward spring, showing first in lesser wing-coverts, then in the scapulars, and lastly in the back. The head, neck, and under parts, which are largely white in the fall, become increasingly white during the winter and spring; and the yellowish suffusion comes in on the head. The secondaries are still all black and the tail feathers. all dusky. By the next summer, when the young bird is two years old, the back and wing coverts are about half white and half black, in a variegated pattern of wholly white and wholly black feathers. Many birds in this plumage are seen in the breeding colonies and are probably breeding.

At the following molt, which begins as early as June, when the bird is two years old, white feathers begin to appear in the secondaries and in the tail, the white feathers in the upper ports increase and the black feathers decrease until the bird is three years old. The summer and fall molt, at this age, probably produces the fully adult plumage in many individuals; but in many cases, perhaps in all, traces of immaturity, such as black secondaries, alternating or scattering through the wings, and black central tail feathers, persist through part of all of the fourth year.

I have seen birds which I call 40 months old in this plumage, but, as late winter and early spring specimens are lacking, I can not say whether these last black feathers are shed before the bird is four years old or not. Certainly at the four-year old molt, if not before that, the plumage becomes adult. During all of this time the young bird has been undergoing an almost continuous molt, represented by two semi-annual molts, much prolonged during the earlier years so that they nearly overlap, but later becoming restricted to a postnuptial and a prenuptial molt in older birds. There is much individual variation in the time required for the various changes.

The adult gannet undergoes a complete postnuptial molt in August and September, which is sometimes prolonged into November, and a partial prenuptial molt, involving the contour feathers and perhaps the tail, during March, April, and May. There is no conspicuous seasonal change in plumage, except that the yellow suffusion on the head is richer and more extensive in the spring and is much paler or entirely lacking in the fall.

Food: The food of the gannet consists entirely of fish, which it obtains by diving in a most spectacular manner. A flock of feeding gannets bombarding a school of herring is a most interesting sight and not an uncommon sight on the New England coast late in the fall. At that season a few gannets are almost always in sight circling high in the air off the coast, looking for migrating schools of fish. As soon as a school is discovered and one or more gannets begin diving, others begin drifting in from all sides, until, in an incredibly short time, a great cloud of birds has gathered; how the welcome news is transmitted so quickly and so far is a mystery; where less than a dozen gannets were in sight a few minutes before, there are now two or three hundred. Over the unlucky school of fish is a bewildering maze of soaring, circling birds, pouring down out of the sky in rapid succession, plunging into the water like so many projectiles and sending columns of water and spray many feet into the air like the spouting of a school of whales. In the center of the mass are the plunging birds hurling themselves at their prey with tremendous force; all around them on the water are the birds which have just risen to the surface to swallow their prey or to rest before trying again and in the air birds are constantly rising, circling, and soaring for the next plunge. It is a lively scene for a while, but it does not last long, as the fish soon become frightened and seek safety in the depths, when the gannets scatter to look for another school.

Dr. Charles W. Townsend (1905) describes the process in detail as follows:

The gannet flies rapidly over tbe water and begins to soar at a height of from 30 to 100 feet, often rising just before the plunge. At the plunge the head is pointed down, the tail up; the wings are partly spread so that the bird appears like a great winged arrow. The speed of the descent is great, and the wings are closed just before reaching the water, which spurts up to a height of from 5 to 15 feet. After the waters have subsided following the splash and all is still, the bird suddenly and buoyantly comes to the surface, the head and neck stretched out first. It then sits quietly on the water for half a minute or so to finish swallowing the prey and to rest, and then slowly and laboriously rises to wind~vard, with its long neck and tail stretched to their full extent. Gaining a height of thirty or more feet, It s~vlngs around to leeward aud is soon soaring and plunglag again. Of eight observations made with a stop-watch on the length of time that this bird remained under water after the plunge, the limit was 4 and 7 seconds, the average being 6j seconds. I also timed them in three descents from height of perhaps 60 feet and found it to be lj, 11, and 1 second, respetively, from the beginning of the descent to the time when they struck the water. This would In~lcate that the bird actually throws itself downward and not merely drops by gravitation, as the distance traveled is too great for such a quick descent by gravity alone. This is apparent without actual measurement, and Is also shown by the fact that the birds sometimes descend quickly at an angle, two often aiming at the same spot. Hoxv they avoid annihilating each other seems marvelous. The height of the descent is, of course, very difficult to judge, but my estimates are based on comparisons with the masts of schooners equally distant. The height of the splash was compared with that of spar buoys near the fishing grounds. As with all other sea birds at a distance, observations were made with a telescope.

The gannet is well protected against bodily injury in its terrific plunges by a strong elastic cushion of air cells under the skin of its breast, whjch softens the shock of impact as it strikes the water. The gannet is a voracious feeder and undoubtedly consumes an enormous number of fish; it is not partial in its choice, though it feeds largely on herring and mackerel where they are abundant in schools: it also takes capelin and other species as well as small codlings. I have heard it said that gannets may be easily killed by fastening a fish on a floating board, for which they will dive and break their necks, though this hardly seems credible. Audubon (1840) describes a method of feeding which I have never seen. “At other times I have seen the gannet plunge amidst a shoal of launces so as scarcely to enter the water, and afterwards follow them, swimming, or as it were moving, on the water, with its wings extended upwards, and striking to the right and left until it was satiated.”

The gannet has a peculiar habit of disgorging whatever fish it has recently eaten when disturbed and forced to fly; it goes through a series of preliminary motions, pumping its neck up and down, straining, gaping, and retching until the fish is finally forced out of its mouth and deposited on the ledge near the nest, where it is left to decay or dry in the sun. These fish are often as much as a foot in length and generally partly digested. I am not sure whether this habit is caused by fright or by a desire to get rid of unnecessary weight; probably the latter, as it is a very docile or very stupid bird and not easily frightened away. It is easily approached with a little caution, and I even caught one in my hands, but usually if I came too near the disgorging process would begin, it would move awkwardly away, uttering a variety of loud guttural croaks or grunts, until it could flop off over the edge of the cliff, spread its long, black-tipped wings and sail gracefully out into space a sudden transformation from an ungainly, awkward, stupid fowl to an elegant, soaring seabird, riding at ease on its broad and powerful wings, one of nature’s triumphs in the balancing of forces.

Behavior: The flight of the gannet is a magnificent performance as it soars aloft on its long, pointed, black-tipped wings, its spearlike head and beak, and its slender tapering tail offering little resistance to the air, as it sweeps in great circles far above the sea until almost lost to sight in the blue sky. When traveling it flies close to the water, flapping its wings and sailing at intervals with wings fully outstretched, after the manner of the pelicans. It is well built for speed and its flight is powerful and long sustained. Its peculiar shape, forming an almost perfect cross while soaring, serves to identify it, as far as it can be seen.

The vigorous plunge of the gannet from a great height, often over a hundred feet, together with the momentum of its heavy body, gives it a decided advantage over other diving birds in reaching great depths. There have been some remarkable stories told of the depths to which gannets dive, based on their having been caught in fishermen’s nets set at known depths. Mr. Gurney (1913) mentions a number of such cases from which I infer that gannets frequently dive to a depth of 60 or 70 feet and occasionally over 100. It is hardly conceivable that the gannet can penetrate to any such great depths as these by the impetus of its plunge; it must, therefore, swim downward, probably using both wings and feet for propulsion. The gannet is not only an expert diver, displaying great agility below the surface, but it is also a strong swimmer above, where it propels itself rapidly with alternate strokes of its great paddles. A wounded gannet is not an easy bird to catch.

I have never heard gannets utter any vocal sound except on their breeding grounds, where they are often quite noisy; they indulge in a variety of soft guttural notes among themselves in conversational tones, and when disturbed a series of loud, grating grunts and croaks, sounding like the syllables “kurru c/c, krrrrruck” or “gorrrrrok, gorrrrok,” the base accompaniment of the never ceasing chorus of sounds in the mixed colonies of Bird Rock. Macgillivray (1852) describes the notes as follows:

Their cry is hoarse and harsh, and may be expressed by the syllables carre, carra, or kirra, kirra, sometimes It Is crac, crac, or cra, era, or cree, cree. The cry varies considerably in different individuals, some having a sharper voice than others, and when unusually Irritated they repeat It with great rapidity.

Gannets quarrel considerably among themselves on their breeding grounds, but I can not find any evidence that they ever molest the other species that breed near them. Morris (1903) describes: A battle between a gannet and two full-grown male swans, the latter both attacking at the same time, and following up the contest most vigorously with the former, who defended himself most resolutely for a very long time, and ultimately defeated the swans, beating them both off, and laying them prostrate, totally disabled, helpless, and seemingly seriously injured. The gannet. much exhausted by the protracted struggle, was easily caught alive, and very little the worse for fighting.

Gannets have never been considered as game birds and the flesh of the adults must be very strong and unpalatal)le, but tbere is plenty of evidence to shoxy that the fat young birds have been largely used for food, particularly in the European colonies. As they are naturally long-lived birds, they would have increased more rapidly than they have done if it were not for this and other natural causes wbich have kept their numbers in check. They are naturally sluggish and somewhat deaf, so that they are easily caught when asleep on their nests or on the water. Mr. Gurney (1913) says that they are frequently choked and killed by attempting to swallow gunnards, “whose spinous dorsal fin may easily become wedged in the gannet’s throat.” They are sometimes killed by plunging into boats containing freshly caught fish, or they become entangled in fishermen’s nets or are caught on hooks baited with fish. Undoubtedly many gannets, as well as other sea birds, starve to death during prolonged periods of rough weather when it is difficult or impossible for them to catch fish. Mr. Gurney (1913) mentions such a disaster, stating that the French ornithologist, M. Baillon, “saw the dead birds lying spread along the shore, and testifies to there having been about 200 gannets, with some 500 razorhills. gulls, etc., on an extent of 4 miles, near the mouth of the Somme.”

Winter: As soon as the gannets leave their breeding grounds they begin their autumn wanderings and southward migrations. They have been seen on the Massachusetts coast in August, but the main flight passes along the New England coast during September and October and extends as far south as the Gulf of Mexico. I have specimens in my collection taken off Cape Cod in both December and .January and a few’ birds winter regularly about Long Island, but usually by November most of the gannets have aone farther south, their movements being governed largely by the migration of the herring. They winter regularly about Florida and in the GluIf of Mexico, where they find an abundant food supply.

DISTRIBUTION
Breeding range: T he Gulf of St. Lawrence (Bird Rocks and Bonaventure and a rock off the south coast of Newfoundland near Cape St. Marys). Formerly near Yarmout.h~ Nova Scotia. on a rock near Grand Manan. Bay of Fundy. and on Perroquet Island, off Mingan. Quebec. On several islands and rocks near the British Isles (St. Kilda, Bass Rock, Ailsa Craig, etc.) and near Iceland (Sulusker, Eldey, and Grimsey). Breeding grounds protected on reservations in the Gulf of St. Lawrence, Bird Rocks, and Bonaventhre.

Winter range: North Atlantic coasts. On the American side rarely from Massachusetts (Cape Cod) regularly from Virginia, mainly at sea, south to Cuba, the Gulf of Mexico, and Mexico (Vera Cruz). South on the other side to the Azores, Canary Islands, and Africa (Morocco).

Spring migration: Mainly off shore. Early dates of arrival (north of Cape Cod, where it may winter): Massachusetts, Lynn, April 8; Nova Scotia, Pictou, April 20. Late dates of departure: Cuba. Cape San Antonio, May 20; Florida, Ormond, March 31; Virginia, Smith’s Island, May; New York, Long Island, May 25; Rhode Island, Block Island, May 16; Massachusetts, Essex County, May 18 (latest June 7).

Fall migration: Early dates of arrival: Massachusetts, Essex County, August 28; Rhode Island, September 10; Block Island, October 4; New York, Montauk Point, October 5.

Casual records: Accidental inland, mainly near the Great Lakes, as far north a~nd west as Ontario (Toronto, December 19, 1908, and Ottawa, October 14, 1909), Indiana (Michigan City, November, 1904) and Michigan (Ann Arbor, October 18, 1911). Recorded on the Labrador coast at 650 north, and in Greenland. Occasional on Louisiana coast (Rigolets, December 9, 1886).

Egg dates: Gulf of St. Lawrence: Twenty records, June 4 to July 25; 10 records, June 16 to July 1. British Isles: Sixteen records, May 9 to June 11; eight records, May 18 to June 7.

About the Author

Sam Crowe

Sam is the founder of Birdzilla.com. He has been birding for over 30 years and has a world list of over 2000 species. He has served as treasurer of the Texas Ornithological Society, Sanctuary Chair of Dallas Audubon, Editor of the Cornell Lab of Ornithology's "All About Birds" web site and as a contributing editor for Birding Business magazine. Many of his photographs and videos can be found on the site.

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