Pacific Loon

The Pacific Loon is a medium size loon with a rounded head shape. Its plumage varies by season.

Photograph © Glenn Bartley

Male/breeding plumage:
– Pale gray head and nape.
– White stripes on sides of neck.
– Dark upperparts with much white.

Sexes similar.

Winter birds are grayish-brown above with whitish underparts.  May show dark chin strap.

Juveniles resemble winter adults.

Ocean, and tundra lakes.

Fish, crustaceans, and insects.

Photograph © Glenn Bartley

Forages by diving.

Breeds in Alaska and northern Canada and winters along the Pacific Coast.

Pacific Loons travel very poorly on land and seldom move more than 100 meters.

During winter, Pacific Loons can occur singly, or in small flocks.

A variety of squawks and yodels are given on the breeding grounds.

The nest is a pile of vegetation.

Number: 2.
Color: Buff with darker markings.

Incubation and fledging: 
– Young hatch at 23-25 days.
– Young fledge (leave the nest) shortly 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 Pacific Loon – the common name and sub-species reflect the nomenclature in use at the time the description was written.

Spring: The Pacific loon is well named, for, except during the breeding season, it is an abundant species along the Pacific coast of this continent. The spring migration is well marked, as the following observation, sent me by Mr. A. B. Howell, will illustrate:

April 12, 1910, detached parties were migrating northward past Ensenada Bay, Mexico, so frequently as to be almost one continuous flock. There were thousands. May 2, 1913, I witnessed a similar flight near Santa Barbara, California.

Mr. Bernard J. Bretherton (1896) says that it arrives at Kodiak Island about the middle of May. On account of its large size, and a habit it has of flying round before it finally alights, makes the arrival of this bird very noticeable. These birds approach the island from the east, flying very high and in pairs, seeming at once to give their attention to selecting a suitable place to nest. They fly from one lake to another, describing large circles in the air, and giving forth their harsh cry, which gives rise to their native name of ‘Ocogara.’ They were never noticed to arrive in the night, as many migrants do.

Mr. John Murdoch (1885) says that, at Point Barrow: they arrive early in June, and before the ponds are open are generally flying eastward as if they had come up along the open water at sea and were striking across to the mouths of the rivers at the east. As the ponds open they make themselves at home there, and evidently breed in abundance, though we were unable to find the nest. One of their breeding grounds was evidently a swampy lagoon some five or six miles inland, but the nests are inaccessible.

Nesting: Mr. W. Sprague Brooks has sent me the following notes on a nest which he found at Demarcation Point, Arctic Alaska, on July 4, 1914:

The nest was on the edge of a shallow slough on the tundra about 200 yards from the shore of the Arctic Ocean. This slough was about 8 acres in area, but another nest was found in one of about half an acre. Enough room to take wing seems to be all that is required. The nest itself was in the aquatic vegetation along the edge and was merely a soaking wet mass of roots, stems, and the accompanying mud, of this same plant torn from the bottom. In the three nests of this species that I found the bird on being disturbed did not show any particular concern, merely awlimuing off to the other side of the slough and keeping an eye on my activities.

Macfarlane (1908) refers to a nest of this species found near Stuart’s Lake, British Columbia, on May 29, 1889, and two nests found early in June, 1890, north of Cumberland House, showing that the Pacific loon breeds far inland. In his notes on the birds of the lower Mackenzie and Anderson Rivers, Macfarlane (1891) says:

This is the most abundant of all the divers in the region under investiga~on. Nests were discovered in the wooded country, in the Barren Grounds, and on the shores and islands of the Arctic coast. In situation and composition they resemble those of U. ember. In all about 165 nests, most of which contained two eggs, were secured in course of the five seasons, from 1862 to 1866, Inclusive.

Eggs: The eggs of the Pacific loon are much like other loon’s eggs, but they average smaller than those of the black-throated loon and larger than those of the red-throated loon. In shape they are “elliptical ovate” or “cylindrical ovate,” usually the former and very rarely nearly “ovate.” The ground color is “Prouts’ brown,” “Saccardo’s umber,” “cinnamon brown,” “dark olive buff,” or “Isabella color,” very rarely “pale olive buff.” The egg is usually sparsely covered with small spots, but often there are a few scattering larger spots, of the darkest shades of brown or nearly black; some eggs show underlying spots or pale shades of lavender or drab. The measurements of 41 eggs, in the United States National Museum, average 75.5 by 47 millimeters; the eggs showing the four extremes measure 87 by 45, 80 by 51, 68.5 by 46, and 70.5 by 44 millimeters.

Young: Nelson (1887) gives the following account of the behavior and food of the young:

When the young can follow their parents all pass to the coast, and during calm, pleasant weather, the last of July and in August, they are very common in all the shallow bays along shore. On one occasion downy young, not over one-fourth grown, were found on August 30. They were in a pond over 2 miles from any place where fish could be found, so that the parents must have flown 4 miles at least for each fish taken to them. One of the young birds had a half digested tomcod about 6 inches long in its gullet, and one of the parents was seen coming in from the seacoast 5 or 6 miles away with a fish of the same size crosswise in its beak.

Plumages: The downy young is plainly colored; the short thick down, with which it is covered, is “light seal brown” on the back, “clove brown” on the sides, head, and neck, and “light drab” on the breast and belly. A specimen in the American Museum, in New York, collected in northeastern Siberia on September 16, 1901, shows the change from the downy stage into the first winter plumage. This is similar to the corresponding plumage of the common loon, but this species can be recognized by its smaller size. In the first winter plumage the under parts are pure white, the throat and sides of the head are largely white, more or less streaked or mottled with dusky, and the upper parts are dark blackish brown; the characteristic feature of this plumage is that the feathers of the back are broadly margined with light gray, giving it a scaly appearance. This plumage is worn during the winter and part of the following spring; when the bird is nearly a year old it begins to show progress toward maturity by a partial molt. Macgillivray (1852) quotes Temininck’s description of this stage in the European bird, as follows:

The young, when a year old, have the head and hin4 neck pale gray; the throat and fore part of the neck white; hut on the throat and sometimes on the fore part of the neck, there appear some violet-black feathers mixed with white feathers; the longitudinal streaked band of the sides of the neck begins to form; the streaks of the lower part of the neck equally appear, and some black feathers without spots, appear on the back, rump, and sides.

A complete, first, postnuptial molt takes place in the latter part of the summer, producing a second winter plumage which is similar to and probably indistinguishable from the adult winter plumage. During the winter and spring further progress toward maturity is made, producing a second nuptial plumage, of which Macgillivray (1852) gives Temminck’s description, as follows:

At the age of 2 years the gray of the head and nape become deeper, and assume a blackish tint, but only on the forehead; the violet black of the throat and forepart of the neck appear, but are variegated with some white feathers; the longitudinal bands are formed; the feathers of the sides and of the upper part of the back, the scapulars, and wing coverts assume the white bands and spots; the upper mandible becomes blackish, but its base, as well as a portion of the lo~ver mandible, are still of a gray color.

Perhaps some individuals may require another year to reach the full maturity of plumage, but probably most birds may be considered adult and acquire their full plumage at an age of 2 years. Certainly during the third autumn, and probably during the second, the adult winter plumage is assumed. This differs from the first winter plumage in being uniformly dark blackish brown above, without any lighter margins on the feathers of the back; the throat and lower half of the head are also purer white, without any dusky Inarkings. The prenuptial molt involes practically all of the contour feathers and the postnuptial molt is complete.

Food: I find nothing published on the food of the Pacific loon except an occasional reference to one being seen flying inland with a fish in its bill, presumably for its young. Small fish probably constitute the principal part of its food.

Behavior: Coues (1877) gives an interesting account of the habits of this species on the coast of southern California; he writes:

They were very plentiful about the Bay of San Pedro. The first thing that attracted my attention was their remarkable familiarity; they were tamer than any other waterfowl I have seen. They showed no concern at the near approach of a boat, scarcely avaiied themselves of the powers of (living, in which the whole family excels, and I had no trouble in shooting as many as I wanted. They even came up to the wharves, and played about as unconcerned as domestic ducks; they constantly swam around the vessels lying at anchor in the harbor, and all their motions, both on and under the clear water, could be studied to as much advantage as if the birds had been placed in artificial tanks for the purpose. Now two or three would ride lightly over the surface, with the neck gracefully curved, propelled with idle strokes of their broad paddles to this side and that, one leg after the other stretched at ease almost horizontally backward, while their flashing eyes, first directed upward with curious sidelong glance, then peering into the depths below, sought for some attractive morsel. In an instant, with the peculiar motion, impossible to describe, they would disappear beneath the surface, leaving a little foam and bubbles to mark where they went down and I could follow their course under water; see them shoot with marvelous swiftness through the limpid element, as, urged by powerful strokes of the webbed feet and beats of the half-opened wings, they flew rather than swam; see them dart out the arrow-like bill, transfix an unlucky fish, and lightly rise to the surface again. While under water, the bubbles of aIr carried down with them cling to the feathers, and they seem hespangled with glittering Jewels, horroxved for the time from their native element, and lightly parted with as they leave it, when they arrange their feathers with a slight shiver, shaking off the last sparkling drop. The feathers look as dry as if the bird had never been under water; the fish is s’vallowed head first, with a curious jerking motion, and the bird again swims at ease, with the same graceful curve of the neck.

Mr. Wilfred H. Osgood (1904) says of its behavior in Alaska:

It was exceedingly abundant along the Chulitna River, where from S to 15 lndividuais were seen almost daily. These were generally seen going up and down the river, flying singly, or more often in pairs, about 100 yards above the water end religiously following the course of the stream. They were quite wary and we seldom approached one on the water nearer than 150 yards, even when we were slipping noiselessly downstream. The adult birds, sittIng on the ‘vater at a little distance, appear as if their heads were entirely white, particularly if a ray of sunlight bears on them. The rapidity with which they swim under water is amazIng, as we repeatedly observed ‘vhen one would dive at a point about 150 yards in front of our canoe and in a few moments appear at aboit the same distance astern.

Macfarlane (1891) says that: The Pacific loon is noted for its peculiarly loud, weird, and prolonged shrill scream during the season of nidification.

Murdoch (1885) refers to the vocal powers of this species as follows:

Their peculiar harsh cry, “kok, kok, kok,” from which they get their name, Kaksau,” is to be heard all summer, and the birds were seen nearly every day, flying backward and forward and inland from the sea. During the breeding season these smaller loons have a habit of getting off alone in some small pond and howling like a fiend for upward of half an hour at a time. It is a most bloodcurdling, weird, and uncanny sort of a scream, and the amount of noise they make is something wonderful, They can be heard for miles.

Fall: The same writer says of their movements in the Fall:

After the breeding season they are frequently to be seen in the open pools along the shore, especially when the lagoons have broken out. They are always very wild and difficult to secure. They are plenty through August and the greater part of September along the shore, and occasional stragglers remain around open holes well into October. Some appeared to be feeding young as late as the middle of September, 1882, as they were seen going inland from the sea carrying small fish.

The fall migration route seems to be straight south down the Pacific coast of North America. The winter range extends from British Columbia southward to Lower California, but the species is apparently most abundant in winter in the southern portion of this range, for it occurs more abundantly on the California coast as a migrant than as a winter resident. Mr. A. B. Howell writes me that: During migration they often gather in flocks of 50 or more just beyond the surf during the heat of the day. While some sleep with their heads beneath their wings, others play, chasing their companions or paddling around on their sides with one foot in the air. They seem to be fond of fishing In company with the cormorants.

DISTRIBUTION
Breeding range: Northern portions of North America. East to the Melville Peninsula (Winter Island), Southampton Island, Hudson Bay, western Tjngava (Long Island, north of Cape Jones), and northwestern Greenland (Carey Islands). South to central Keewatin (York Factory), southern Mackenzie (Great Slave Lake), central British Columbia (Stuarts Lake) and southwestern Alaska (Kodiak Island and Alaska Peninsula). West to Bering Sea. North to northwestern Alaska (Point Barrow), Banks Land, and the entire Arctic coast of Alaska and Mackenzie. Also northeastern Siberia ~vest to the Indigirka River.

Turner records them as present throughout the year in the Aleitian Islands and breeding on the Near Islands (Semichi). Recorded in summer and may occasionally breed in Queen Charlotte Islands (Skidegate, several July 9), southern Alaska (Sitkan district, few pairs; Admiralty Island, few pairs remain), Herald Island (two taken in June), Kuril Islands (Simushir) and Japan (near Ilakodadi July 13). May occasionally reach northern Labrador and southern Greenland.

Winter range: South mainly along the Pacific coast. From southern British Columbia (Puget Sound region) to Lower Cali-. fornia (at least, to San Quentin Bay, perhaps farther south). Some Alaskan birds may winter on the Asiatic coast (Japan, Tojiri, one taken March 14) and in the Aleutian Islands; and it is possible that individuals from the interior may pass the winter in the southern part of James Bay.

Spring migration: Northward in April and May. Lower California: San Quentin Bay, April 12; Coronados Islands, May 15. California: Santa Cruz Island, April 12 to 15; Santa Barbara, April 28 to May 4; Monterey, occasionally to June 10. Southeastern Alaska: Forrester Island, May 1 to 25; Admiralty Island, May 5. Northwestern Alaska: Yukon mouth, May 15 to 25; Kotzebue Sound, May 26 (earliest); Point Barrow, June 4, 1882, and June 13, 1883. Arctic coast: Demarcation Point, June 3. Dates for the Mackenzie region are late, July 2 being the earliest at Fort MacPherson. Yukon Territory: Forty Mile, May 28. Melville Peninsula, June 28.

Fall migration: Southward in September. Last seen at Hudson Bay: Cape Churchill, August 24. Mackenzie: Great Bear Lake, September 9; mouth of Coppermine River, taken in October. Northwestern Alaska: Point Barrow, September 28 (and later) ; St. Michael, September 16. Southeastern Alaska: Valdez Narrows, September 18. They arrive on the coast of California during September; the single Arizona bird was taken September 20 and a Colorado (Breckenridge) bird November 15.

Casual records:

Eggs: Guadaloupe Island (one found dead in 1875), Arizona (Fort Verde), New Mexico (near Clayton), Iowa (near Sabula), and New York (Long Island, April 29). The Long Island and Iowa birds have been erroneously recorded as aretica.

Egg dates: Mackenzie: 57 records, June 10 to July 23; 30 records, June 23 to July 4. Northern Alaska: 8 records, June 15 to July 6; 4 records, June 17 to 30. Hudson Bay: 3 records, June 8, July 1 and 14. GAVIA STELLATA (Pontoppidan).