Gadwall

The Gadwall is a dabbling duck similar in size and proportion to the Mallard.

Males are mostly gray, with fine white vermiculations. They have black bills and black rumps.  Length: 20 in.  Wingspan: 33 in.

Females are mostly brownish, with orange and black bills.

Males in nonbreeding plumage lack much of their breeding color, and appear similar to females, though they have silver tertials.

The immature Gadwall is similar to the adult females but has a paler face.

Gadwalls inhabit ponds, lakes, and marshes.

Gadwalls primarily eat plant material such as leaves and stems of aquatic plants, though insects and mollusks may also be consumed.

Gadwalls forage by gleaning food from the surface of the water, or by tilting head-first into the water.

Gadwall occur throughout much of the U.S. and Canada, breeding from the central U.S. north, and wintering across a broad swath of the central and southern U.S., as well as the Pacific states and provinces. They are less common in the east. The population has increased in recent decades.

More information:

Bent Life History

Visit the Bent Life History for extensive additional information on the Gadwall.

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.

• Male, adult, Washington, July
• From below
• Female, adult, Washington, Nov.
• From below

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

Gadwall nests are sometimes parasitized by other hens, and have even been known to be parasitized by Ring-necked Pheasants.

Northern populations are migratory, though southern populations may be resident.

Female Gadwall give a “quack” similar to female Mallards.

Gadwall nests are a shallow depression lined with grasses and down, and situated on land but near water.

Number: Usually lay 7-12 eggs.
Color: White or gray.

Incubation and fledging:
The young hatch at about 26 days and leave the nest almost immediately, but are not fledged until about 7-9 weeks of age.

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

The arrival of the ducks on their breeding grounds in the great wildfowl nurseries of northwest Canada is a spectacular performance. I shall never forget the sights I saw, one cold, rainy day, June 13, 1905, as I walked down toward the great sloughs at the head of Crane Lake, Saskatchewan; hundreds of ducks arose from the wet meadows, from the sloughs, and from an island in the lake, flying around in great loose flocks; a great cloud of them rose, like a swarm of mosquitoes, from the mouth of Bear Creek; most of them were gadwalls, but there were also large numbers of canvasbacks, redheads, shovellers, and blue-winged teal, as well as lesser numbers of lesser scaups, mallards, baldpates, and ruddies, with a few Canada geese; the air seemed to be full of ducks, flying in all directions in bewildering clouds; I have never seen so many ducks before nor since. This was the center of their abundance in one of the greatest duck-breeding resorts I have ever seen. Probably all of the ducks had arrived on their breeding grounds at that time, but evidently many of them had not mated and others had not finished laying.

On June 17, 1905, Mr. H. K. Job and I made a careful census of the ducks breeding on the island, referred to above, by dragging a long rope over it as thoroughly as we could and by noting and recording the nests found by flushing the birds. The island was about 300 or 400 yards in length by about 100 yards in width, fairly high at one end and everywhere covered with a thick growth of grass, through which were scattered on the higher portion numerous small clumps and in some places large patches of rose bushes, offering ideal conditions as a breeding ground for ducks. There were several small ponds near the center of it lined with fringes of cattails and bull- rushes. On the lower portion of the island the grass was shorter, and where it extended out into a point the ground was bare. A colony of common terns occupied this point, which was also the favorite re- sort of a flock of white pelicans, which may have bred here later in the season. Marbled godwits, Wilson phalaropes, and spotted sandpipers were breeding here, as well as western savanna sparrows.

A pair of crows had a nest in the only tree on the island, a small willow, and they must have fared sumptuously on stolen duck’s eggs. A pair of short-eared owls had a nest on the island containing young in various stages of growth. We were unable to drag the whole island, as the rose bushes were too thick in many places, but in the course of two hours’ work we recorded 61 nests, as follows: Mallard, 5 nests; gadwall, 23 nests; baldpate, 3 nests; green-winged teal, 2 nests; blue-winged teal, 10 nests; shoveller, 7 nests; pintail, 8 nests; and lesser scaup duck, 3 nests. The ducks were identified to the best of our ability by eyesight; the female gadwalls and baldpates were very difficult to distinguish and there may have been more of the latter than we supposed, but certainly both the species were nesting there, as we saw a number of males in the small pondholes; the green-winged teals’ nests were identified by seeing the female join a male of that species. We started a number of ducks, mostly pintails, where we failed to find nests, which probably meant broods of young and which were not counted. Most of the sets were incomplete or fresh, indicating that the ducks were only just beginning to lay; we therefore must have overlooked a great many nests, where the eggs were covered and no ducks flushed, as we found a number of such nests by accident. Considering these facts, making allowance for the unexplored parts of the island and judging from the immense numbers of ducks that were flying about or bedded out on the lake, I considered it fair to assume that at least 150 pairs of (lucks were breeding or preparing to breed on this one island. In addition to the species above re- corded, we saw on the island several American mergansers, a white- winged scoter and one cinnamon teal, making a total of 14 species of ducks which were probably breeding on the island or in sloughs around it. As may be imagined, it was with considerable interest and pleasant anticipation that I revisited this island in 1906, but I was most keenly disappointed to find it practically deserted. Instead of the immense flocks of ducks which I had seen rise from the sloughs like clouds of mosquitoes, only a few scattered flocks were seen. As we walked across the island expecting to see ducks flying up all about us, hardly a duck arose, and in place of the 60 odd nests that were expected to find only 3 nests were found. The mystery was soon solved by finding a nestful of broken eggs and bunches of yellowish hair clinging to the rose bushes. A coyote had been living on the island and had cleaned out all of the nests, and driven the ducks away. The destruction of the bird population of the island had been still further carried on by a family of minks and the entrance to their burrow was strewn with feathers. Whether the ducks will ever return to this island or not is an open question, but probably they have moved to some safer spot.

The prevailing impression which seems to exist in the minds of many writers that the gadwall is nowhere an abundant species should be dispelled by the foregoing account of its abundance in Saskatche- wan, where it was at that time, and probably still is, the most abundant of all the ducks. It is undoubtedly steadily decreasing, as all the other ducks are, for advancing civilization and the demands of agriculture are usurping its breeding grounds. If a few such places, as I have just described, which are not particularly valuable for agricultural purposes, could be set apart as breeding reservations for waterfowl, this and many other species might be saved from extermination, which otherwise seems inevitable. Since the above was written I have learned from Mr. Hoyes Lloyd that much of the land around Crane Lake has been secured by the Canadian Government and that the locality described above will be included in an extensive bird reservation.

Courtship: Dr. Alexander Wetmore (1920) has given us the follow- ing interesting account of the courtship of the gadwall:

The mating flight of the gadwall is always interesting and is seen constantly when the birds are on their breeding grounds. Here at Lake Burford opportunities for observing it were excellent. The flight was usually performed by two males and one female. In the beginning two males approached a female in the water, calling and bowing. She usually rose at once and flew with a slow flapping flight, mounting in the air with the males in pursuit, calling and whistling constantly. First one and then the other of the males swung in front of her, set his wings, inclined his body upward to show his handsome markings, and, after a few seconds, dropped back again to his former position. Late in the season there was always one of the males who was favored and who displayed more often than the other, flying close to the female, so that in passing his wings often struck hers, making a rattling noise. After a short time the second male often left the pair and returned to the water. The birds frequently mounted until they were 800 yards or more in the air, and darted quickly from side to side, flying now rapidly and now slowly. When the flight was over the birds descended swiftly to the water again. I was never able to ascertain whether there were some extra males about or not, as, though, there were usually two with the female in this flight I found them at other times always in pairs.

The female gadwall, like the mallards, also came out in the short grass of the shore and walked about with head down, quacking loudly, an action that I took for part of the mating display.

When the birds were in the shelter of the rushes they went through other mating actions of interest. The male swam toward the female bowing by extending his neck until the head was erect and then retracting it, bringing his bill down onto his breast. He then approached pressing his breast against the sides of the female and shoving her easily, first on one side and then on the other, biting her back and rump gently as he did so. Alter a few seconds she lowered her body in the water and copulation took place with the female entirely submerged save for the crown of her head while half of the body of the male was under water. As the female emerged the male turned immediately to face her and bowed deeply, giving a deep reedy call as he did so.

Nesting: In North Dakota, in 1901 we found the gadwall breeding quite commonly on the islands in the larger lakes, particularly on the islands in Stump Lake which are now set apart as a reservation and protected. Baldpates and lesser scaup ducks were breeding abundantly on the same islands, far outnumbering the gadwalls; there was also a breeding colony of double-crested cormorants on one island and colonies of ring-billed gulls and common terns on two of them. The gadwall’s nests were usually well concealed in thick rank grass, tall reeds, dense clumps of wild rye, or patches of coarse weeds; they were always on dry ground and never very near the water. The nests consisted of hollows scooped in the ground and well lined with strips or pieces of reeds, bits of dry grass, and weed stems, or. whatever material could be most easily gathered in the vicinity, mixed with the down from the bird’s breast; with incomplete sets or fresh eggs very little down is found, but as incuba- tion advances the down is added until the eggs are surrounded and sometimes entirely covered with a profusion of dark gray down, which is usually mixed with bits of grass or straw.

Although the gadwall seems to prefer to nest on islands we found a number of nests in Saskatchewan in meadows or on the open prairie at long distances from water, where we flushed the birds fron I their nests as we drove along; such nests were well concealed in thicl grass, which was often arched over them, or were hidden under small sage or rose bushes. I have always found the gadwall a close sitter, flushed only when closely approached, but Mr. W. L. Dawson (1909) has noted variations in this respect, as follows:

The birds behavior when surprised depends altogether upon the stage of incuba- tion reached. In general, the bird sits close until discovered; after that, if the eggs are fresh, the duck may flee upon sighting her enemy a hundred yards away; but if the eggs are near hatching, she will endeavor to lead the investigator astray by painfully dragging herself through the grass. If too much harassed, however, she will desert her eggs outright rather than wait for what she regards as an inevitable doom, and the same remark will apply to almost any of the nesting ducks.

‘I’he down in the nest of the gadwall is smaller than that of the mallard, darker colored, and otherwise different in appearance. In color it is dark “hair brown,” almost “fuscous,” with whitish centers and grayish tips. The breast feathers mixed with the down are characteristic of the species, small, light colored, and with van- able patterns of dusky markings in the center, but with light, tips. It. is difficult to distinguish, in the field, the nest of the gadwal] from that of the baldpate, as the eggs of the two are indistinguishable, and the females are much alike. But the gadwall has more white in the speculum, the bill is yellower, and the breast is spotted, all difficult polnts to see as the female flies from the nest.

Eggs: The gadwall lays from 7 to 13 eggs, but the usual set consists of 10, 11, or 12 eggs. I have occasionally seen one or two eggs of the lesser scaup duck in a gadwall’s nest, and Mr. William spreadhorough, “on June 29, 1894, at Crane Lake, Saskatchewan, took a nest of this species containing 13 eggs, 7 of which were of the lesser scaup,” according to Macoun (1909). Undoubtedly the bald- pate occasionally lays in the gadwall’s nest, as the two species are often intimately associated, but the eggs arc nearly indistinguishable.

The eggs of the gadwall are nearly oval in shape and are usually shorter and more rounded than those of the baldpate, but there is much individual variation in both species. Their color is a dull creamy white, somewhat whiter than the baldpate’s on the average. The measurements of 100 eggs in various collections average 55.3 by 39.7 millimeters; the eggs showing the four extremes measure 59.5 by 39.5, 57.5 by 43.5, 49.5 by 38 and 51 by 34.5 millimeters. The period of incubation, which is performed wholly by the female, is about 28 days.

Plumage: The downy young of the gadwall is very much like that of the mallard, except that it is decidely paler and less richly colored; the pale yellow of the under parts is more extensive on the sides and head extending nearly around the neck where it is separated by a nalTow dark stripe on the nape, the light superciliary stripe is broader; the dark loral and postocular stripe is narrower and the uricular spot is hardly noticeable. The upper parts are “bister,” deepening on the crown to “bone brown”; the under parts are “cartridge buff,” paler on the belly and deepening to “cream buff” or “Naples yellow” on the neck an(l sides of the head; the light patches on the scapulars and sides of the rump are huffy white.

The young birds become paler as they grow older. The plumage develops in the same sequence as in the mallard. Young birds gradually develop, during the first fall and winter, a plumage closely resembling that of the adult; by the month of March this first winter, or first nuptial, plumage is generallycomplete: there are usually a few spotted feathers scattered over the under parts, as signs of immaturity and the wings are much duller than those of adults, with little if any chestnut in the coverts. The molt into the eclipse plumage begins in June and during the transitions of this first. double molt, young birds become indistinguishable from adults.

Adult males begin to molt into the eclipse plumage about the last of May or first of June and by the end of June many dark, brown- edged feathers, like those of the female are scattered through the breast and flanks. I have seen males in full eclipse as early as Au- gust 10 and as late as September 8: this plumage is an almost com- plete reproduction of the female’s, or young male’s, excepting, of course, the wings, which are molted only once in August. The molt out of the eclipse plumage consumes about two months; I have seen birds in this molt from September 8 to November 23, but I am in- clined to think that old drakes usually attain their full plumage by November 1st or earlier. There is no winter or spring molt in old birds. ilybrids occur occasionally; Mr. William G. Smith (1887) mentions a beautiful male hybrid in which the color and size were about equally divided between the gadwall and the baldpate; he also “killed two specimens of gadwall with a distinct black ring about the neck. They were male and female and were together.”

Food: Like the mallard, the gadwall is a clean feeder, which makes its flesh desirable for the table. It consumes a great variety of food, most of which is obtained by tipping or dabbling about the edges of marshy ponds, sloughs, or grassy, sluggish streams; it can dive well for its food, howe’ver, when necessary. Its vegetable food consists of tender grasses, the blades, buds, seeds, leaves, and roots of various aquatic plants, nuts, and acorns; it visits the grain fields to some extent, where it picks up wheat, barley, buckwheat, and corn.

According to Mr. Douglas C. Mabbott (1920):

In habits the gadwall resembles the mallard, feeding either on dry land or in shal- low water near the edges of ponds, lakes, and streams, where it gets its food by “tilting” or standing on its head in the water. The food of both the gadwall and the baldpate, however, is quite different in some respects from that of the mallaid. These two feed to a very large extent upon the leaves and stems of water plants, paying less attention to the seeds, while the mallard feeds indiscriminately on both or even shows some preference for the seeds. In fact, in respect to the quantity of foliage taken, the gadwall and the baldpate are different from all other ducks thus far examined by the Biological Survey. They are also more purely vegetarian, their diet including a smaller percentage of animal matter than that of any of the other ducks.

As computed from the contents ol 362 stomachs collected during the six months from September to March, 97.85 per ceut o’ the food of the gadwall consists of vege- table matter. This i5 made up as follows: Pondweeds, 42.33 per cent; sedges, 19.91; algae, 30.41; coon tail, 7.82; grasses, 7.59; arrowheads, 8.23; rice and other cultivated grain, 1.31; duckweeds, 0.61; smartweeds, 0.59: wild celery and water weed, 0.53; water lilies, 0.52; madder family, 0.37; and miscellaneous, 2.61 per cent.

Considerably more animal food i5 taken in summer than in winter, owing, of course, to the fact that more is available at that time of the year. The percentage of animal food for the summer months is higher also because there are included in the averages analyses of numerous stomach contents of ducklings, which feed to a great extent upon insects. All of the 11 stomachs collected during the month of July (9 from North Dakota and 2 from Utah) were of young ducklings. A computa- tion of the average contents of this series produced the following results: Water bugs, 56.18 per cent; beetles, 7.09; flies and their larvae, 2; nymphs of dragon flies and damsel flies, 0.27; other insects, 2; total animal food, 67.54 per cent; poudweeds, 12.55 per cent; grasses, 5.09; sedges, 2; water milfoils, 0.55; smartweeds, 0.09; mis- cellaneous, 12.18; total vegetable food, 32.46 per cent.

The animal food of adults includes small fishes, crustaceans, tad- poles, leeches7 small mollusks, water beetles and other insects, larvae, and worms.

Behavior: The gadwall can walk ~vell on land, where it forages for oak mast in the woods and for grain in the open fields, often a long distance from water. It takes flight readily from either land or water, springing into the air and flying swiftly away in a straight line. When migrating, it flies in small flocks of about a dozen birds; in appearance and manner of flight it greatly resembles the baldpate, but the male can usually be distinguished from the latter by the white speculum and the brown wing coverts; a similar difference exists between the females, but only to a slight degree; practiced gunners claim to recognize other field marks, but they have proven too subtle for my eyes, and I have frequently mistaken one species for the other. The gadwall ought not to be mistaken for any other species, except the baldpate or the European widgeon, but it fre- quently is confused, by ignorant gunners, with the young males and females of the pintail, though its flight and general appearance are entirely different; the name “gray duck” has been applied to both the gadwall and the pintail, which has led to much confusion of records and to erroneous impressions as to the former abundance of the gadwall in New England, where, I believe, it has always been a rare bird.

Doctor Wetmore (1920) describes the notes of the gadwall as follows:

The call note of the female is a loud quack that is similar to that of the female mallard but is pitched slightly higher and is not quite so loud and raucous. Considerable experience is required, however, to distinguish with certainty the calls of the two birds. The male baa a loud call like kack kock, a deep reedlike note resembling the syllable whack, and a shrill whistled call.

The gadwall associates freely with other species of similar habits and tastes, particularly with the baldpate and pintail, with which it seems to be on good terms.

Game: There seems to be a difference of opinion among sports- men as to the food value of the gadwall; some consider it a close second to the mallard and others say it is hardly fit to eat; probably this is due to the different kinds of food that it lives on in various localities.

Mr. Dwight W. Huntington (1903) writes of his experience in shooting it:

I found it fairly abundant in North Dakota and usually shot a few gadwalls with the other ducks. One day when shooting on a little pond quite near the Devils Lake, I shot a large number of ducks, and nearly all of them were gadwalls. They came quite rapidly toward evening, and standing in the tall rushes without much effort at concealment, I had some very rapid shooting. Far out on the lake the swans and geese were trumpeting and honking. Large flocks of snowgeese, or white brant, as they call them in Dakota, were always in the air; the mallard, sprigtails, teal, and all the ducks were flying everywhere; but the gadwalls were the only ducks which came to me in any numbers. Had I put out only gadwall decoys, there might have been a reason for this, but I had no decoys that day at all. In fact the ducks were always so abundant that I could kill far more than I could carry, without decoys, and an ambulance from the garrison came out to carry in the game.

Winter: As the gadwall is one of the later migrants northward in the spring, not appearing usually until the ice is all out of the ponds, so it is also one of the earlier ducks to leave in the fall and start on its short flight to its winter home in the Southern States, principally in the lower Mississippi valley, and in Mexico. The gad- wall is primarily a fresh water duck, breeding far in the interior and wintering principally in the inland ponds, marshy lakes, sloughs, and swamps, where it can find mild weather and plenty of food; but it frequents to some extent the brackish pools and estuaries along the coasts of Louisiana and Texas, where it is very common. Messrs. Beyer, Allison, and Kopman (1906) say of its winter movements in Louisiana:

As in the case of the mallard, the first came by the early or the middle part of October, and continue to increase decidedly until the middle of December, then remaining in statu quo or showing something of a decrease, according to the nature of the winter, until the middle of January. A strong northward movement begins at that time, and while it consists largely of individuals that have wintered in Louisiana, it is doubtless augmented also by the first passage of transients. This later movement continues more or less freely until about March 15, after which date, duck migration is restricted almost entirely to a few species, among which the gadwall is seldom if ever found.

DISTRIBUTION
Breeding range: Temperate regions of the Northern Hemisphere. In North America, east to Hudson Bay (Churchill), southeastern Manitoba (Shoal Lake), southern Wisconsin (Lake Koshkonong, formerly), and formerly in Ohio. South to central Minnesota (Becker County), northern Iowa (Kossuth County), southwestern Kansas (Meade County), southern Colorado (La Plata County and San Luis Valley), northwestern New Mexico (Lake Burford), southern Cali- fornia (San Jacinto Lake, Riverside County). West to the interior valleys of California (San Joaquin and Sacramento valleys), Oregon (Camp Harney), and Washington (Brook Lake). North to central Alberta (Lesser Slave Lake), and northern Saskatchewan (Athabasca Lake). Has been found breeding casually on Anticosti Island, Gulf of St. Lawrence. In the Eastern Hemisphere, Iceland and the temperate regions of Europe and Asia, from the British Isles, Denmark, Sweden, and Holland to Kamchatka; also southern Spain and northern Algeria.

Winter range: Southern States and Mexico, east to the Atlantic coast from Maryland (Chesapeake Bay) to southern Florida. South to Jamaica, rarely, south central Mexico (Guadalajara), and southern Lower California (San Jos6 del Cabo). West to the Pacific coast. North rarely to British Columbia (Chilliwack) more commonly to the coasts of Washington (Puget Sound region), and Oregon, Utah, northeastern Colorado (l3arr Lake), northern Arkansas (Big Lake), and southern Illinois (Mount Carmel). In the Eastern Hemisphere, the British Isles, the Mediterranean basin, northern Africa (to the Sudan and Abyssinia), northern India, China, and Japan.

Spring migration: Early dates of arrival: Iowa, southern, March 10; Minnesota, Heron Lake, March 17; Montana, Terry, April 1; Manitoba, Aweme, April 23; Saskatchewan, Indian Head, April 18; Alberta, Edmonton, May 5. Late dates of departure: Lower Cali- fornia, Colnett, April 8; Oklahoma, Caddo, April 2.

Fall migration: Early dates of arrival: Lower California, southern, September 27; Massachusetts, Essex County, October 2; Rhode Island, October 8. Late dates of departure: Ontario, Ottawa, October 29; Rhode Island, Point Judith, November 11; Long Island, Oakdale, December 13.

Casual records: Accidental in Bermuda (December, 1849) and Alaska (St. Paul Island, November 13, 1911).

Egg dates: North Dakota: Twenty-seven records, May 18 to July 16; fourteen records, June 7 to 19. Manitoba and Saskatchewan: Twenty records, June 6 to July 3; ten records, June 13 to 27. Cali- fornia and Utah: Sixteen records, April 16 to July 20; eight records, May 15 to June 17.