Short-eared Owl | Life Histories of North American Birds | A.C. Bent
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Life Histories of Familiar North American Birds
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Short-eared Owl
Asio flammeus

Contributed by Charles Wendell Townsend
[Published in 1938: Smithsonian Institution United States National Museum Bulletin 170 (Part 2): 169-182]

The short-eared owl is one of the most cosmopolitan of birds, as it is found in every continent except Australia. In its habits it differs from most owls in preferring open plains, marshes, and sand dunes to thick forests, where it is almost never seen, and in the fact that it frequently hunts by day. Although it sometimes takes small birds, its feeding habits in general are of great value to man, for its favorite food consists of rodents. When field mice or voles increase so as to become veritable plagues, various owls, especially of this species, have been known to congregate in the infested region and to have done great service in destroying the pests. There are several such records in various counties in England extending back to the sixteenth century. Such a plague of mice is described by Hudson (1892) as occurring in South America in 1872-73, when short-eared owls were most important agents in stopping the plague. Notwithstanding their proved value, ignorant and thoughtless gunners continue to shoot these beneficial birds, and their numbers are diminishing.

Courtship.--The remarkable courtship flight and song of this bird have been well described by A. D. DuBois (1924), who not only made observations on the song at night, but on both song and flight by day. The song consisted of a series of toots "repeated fifteen to twenty times, at the rate of four toots per second, in a low-pitched monotone." The sound seemed

to come from all directions. Finally, upon gazing upward, I discovered the owl directly overhead, and for a time was able to watch him, with the field-glass, in the fading light. He was flying at a great elevation; so great in fact that it was difficult to see him at all without the aid of the field-glass. For the most part his flight was with slow, silent flapping wings, although he sometimes soared. His course led in easy curves which kept him in the same general locality. His song, on this occasion, was made up of 16 to 18 toots. Now and then he made a short slanting dive which terminated with an upward swoop. The dive was accompanied by a peculiar fluttering noise. . .a sound as might be produced by a fluttering small bird imprisoned in a box, or by the flutter of a small flag in a very strong wind.

Later, DuBois observed the flight in full sunlight and was able to solve the mystery of the "fluttering flag." "When the owl began the short dive he brought his wings together beneath him, stretching the back posteriorly and striking them rapidly together with short clapping strokes. The dive ended simultaneously with the clapping, when the bird spread his wings, abruptly and noiselessly turning his course upward with a swoop. The clapping was clearly visible with the field-glass and the fluttering sound produced by it was distinctly audible. He seemed to be applauding his own aerial performance." Mr. DuBois observed this flight song during four years, on the Great Plains in Montana between March 17 and August 28. In the later dates the young are already partly grown. On one occasion when he had examined a nest of four young and had seated himself at a distance, one parent disappeared, "the other flew and soared in circles above me, gradually climbing until it was at a great height. During the time that I watched, he twice indulged in wing-clapping. Having thus spiraled upward above me to his maximum height, he shifted his center of flight to a point more nearly over the nest, at the same time reducing his elevation."

Francis Harper writes that he observed the courtship flight of this owl at Gardiners Island, N.Y., in 1911 and thus describes it: "Late in the afternoon of June 14 I noticed one of the owls high up in the air, flying with exceptionally slow and somewhat jerky wing strokes at the rate of 150 a minute and making scarcely any headway. There seemed to be almost a perceptible pause of the wings as they reached their highest point, before beginning the downward stroke. Now and then the bird would swoop downward, meanwhile striking its long wings beneath its body, perhaps 8 or 12 times in the space of a second or two. It was a remarkable act, quite unlike anything known to me among other birds. The owl kept more or less over a particular part of the pasture and was probably 200, or even 300, feet in the air at times."

Edward A. Preble (1908) reports that several individuals of this species were seen on April 30, 1901, to the north of Edmonton, Alberta. "They were usually flying in pairs, and the males frequently swooped down toward their mates from a considerable height, holding their wings high above the back and uttering peculiar quavering cries."

Nesting.--The short-eared owl nests on the ground generally in a slight depression very sparsely lined with grasses and weed stalks and an occasional feather. Sometimes the nest seems to consist only of the flattened dead vegetation of the spot chosen, or merely a slight hollow in bare sand. It may be entirely exposed to light in an open field or marsh or partly hidden by a clump of grasses or weeds. A. K. Fisher (1893b) says that "in exceptional cases it has been found in a clump of low bushes, or otherwise slightly elevated."

Coues (1874) quotes Dall who had found the short-eared owl "breeding in burrows on the island of Oomalashka; 'the hole is horizontal, and the inner end usually a little higher than the aperture; lined with dry grass and feathers.' The burrows were not over two feet deep, usually excavated in the side of a steep bank."

A few descriptions of individual nests will serve to show their character. A. D. DuBois thus describes a nest in Montana: "The nest was situated on almost level ground--on the slight west slope of a knoll, amid the young growing wheat and the old last year's stubble. It was a shallow depression in the earth, sparingly lined with old wheat straws and the shredded husks of the stubble. There were a few soft feathers about the edges. A dried Canada thistle, remaining from the previous year, afforded slight protection on the east."

Charles A. Urner (1923) described a nest in a salt marsh near Elizabeth, N.J. The nest "was composed almost entirely of salt hay and about nine inches in diameter and an inch and a half to two inches thick. . . . The ground, immediately about the nest for a distance of four inches had apparently been almost cleared to furnish material and on one side the thick stubble still stood as if the matted dried grass had been broken off by the bird's bill. The presence of feathers (apparently owl's feathers) throughout the mass of the nest furnished additional evidence that this species of owl actually constructs its own nest."

J. Claire Wood (1907) thus describes a nest found in Michigan: "It was a mere platform of dead marsh grass half an inch thick and covering a spot of bare ground ten by eighteen inches. The long 'saw-grass' formed an arch over the nest, but there was an opening at the easterly end leading into an open space about two feet wide by four long--a sort of play and feeding grounds for the young." The nest and vicinity were kept clean of all castings, down, feathers, etc., that would tend to betray its existence. On the other hand, nests and their vicinity are often foul with droppings, feathers, and pellets.

Bendire (1892) describes two nests found in Idaho on the ground, "one in the center of a tall bunch of rye grass, the other by the side of one of these, and both were well hidden. . . . They were simply slight depressions not more than 2 inches deep, lined with pieces of dry grass and a few feathers from the birds."

That the short-eared owl may occasionally return to the same nesting site seems to have been shown by Urner (1923) who discovered directly under a new nest in 1922 "a more or less discolored white egg, one side slightly cracked as if from freezing, the dimensions corresponding to the egg of the short-eared owl. . . . Under the cracked egg could still be seen the outline of a well-rotted nest, presumably from the 1921 season."

Eggs.--[AUTHOR'S NOTE: The short-eared owl may lay anywhere from four to nine eggs, and rarely even more; but the commonest numbers are five, six, or seven. The eggs vary in shape from oval to elliptical-ovate. The shell is smooth, or very finely granulated, with very little, if any, gloss. The color is white, or very faintly creamy white.

The measurements of 56 eggs, in the United States National Museum, average 39 by 31 millimeters; the eggs showing the four extremes measure 44 by 32.5, 40 by 33, 37.5  by 29.5, and 38.5 by 29 millimeters.]

Young.--The incubation period according to Bendire (1892) is about three weeks. F. L. Burns (1915) states it to be 21 days. Both sexes incubate and take care of the young. According to Urner (1923) the young fly in from 31 to 36 days after being hatched and remain in the vicinity of the nest for six weeks, although they stray from it and hide in the surrounding grass long before they can fly, sometimes as early as two weeks from hatching. Owing to their protective coloration, they are found with difficulty in the grass, and as they stretch out motionless on the ground this difficulty is increased. When aroused they turn on the back and fight. Mabel Densmore (1924) describes the actions of a young bird full grown but unable to fly that she discovered, "a bundle of feathers, dumped down in the short prairie grass, with no semblance to a bird except the eyes." While the parents flew excitedly around, the young continued to "play possum" and could be moved about and handled freely without showing a sign of life except in its eyes.

Nearly all the young of short-eared owls found at or near the nest differ in size and in development of plumage. Aretas A. Saunders (1913) measured each of nine young of one pair and concluded that their ages ranged between 3 and 14 days. He also found that each owl at about the age of two weeks strayed from the nest, going farther and farther each day even to a distance of 100 or 150 yards. He was always able to find the young by the action of the parents in feigning injury nearby.

Urner (1923) concluded from his observations in the salt marshes of New Jersey that short-eared owls sometimes move their eggs or helpless young to escape unusually high tides, and it is probable that when the eggs are destroyed by high tides or prairie fires, a second set is laid.

Urner (1921) describes the "wounded bird" actions of a short-eared owl flushed from a nest of young in New Jersey: "The first bird flushed strove vainly by imitating injury and distress to draw me away, these exhibitions including sheer drops or tumbles from the air and flutterings and cries with wings outspread while on the ground. When not thus engaged the bird maintained a position directly overhead facing the wind. The second adult when flushed from the nest, joined the vigil overhead." The wounded-bird act differs in intensity and may or may not be accompanied by calling. On one occasion the excited bird struck his hat twice. The same author (1923) has this to add: "An interesting performance occasionally seen when the nest is visited is a steep dive toward the ground by the adult, the outstretched wings being brought together under the body as the bird descends, the ends being clapped together rapidly, the sound being distinctly audible when the bird is within one hundred feet." This is an illustration of use of part of the courtship performance by birds at moments of intense excitement, even when not connected with the amatory instinct.

Saunders (1913) describes the wounded-bird act as follows:

The bird circles at a height of about fifty feet, then drops straight down close to the intruder until within two or three feet of the ground, then sails low over the grass and brush in the opposite direction from the nest until a hundred feet of more away when he lights on the ground facing the intruder, squealing as though in great pain, and with wings widespread and flapping. If followed he will wait till one gets within about twenty-five feet, then slowly and carefully folds his wings one at a time, rises and sails a little farther away and repeats the wing flapping and squealing. If one is not watching him when he first drops to the ground, he frequently calls attention to himself by flapping his wings against his sides or breast as he drops, producing a sudden loud and startling noise that is very surprising in a bird whose flight is ordinarily perfectly silent.

An amusing variation of the wounded-bird act is given by Kitchin (1919): "We were here treated to a most ridiculous performance by the male bird. While watching the female we suddenly heard an awful groaning and chuckling sound behind us. This was the male and he was mad clear through, darting back and forth and uttering these awful sounds. Finally, he could stand it no longer and literally dove into a bunch of high weeds, where he twisted and turned, and to watch the tops of the weeds one would think that nothing less than a death struggle was going on."

Plumages.--[AUTHOR'S NOTE: When first hatched the nestling is fairly well covered with rather short soft down, grayish white or buffy white above and nearly pure white below. Witherby's handbook (1924) says: "Base of down dark brown along wing, at base of wing and on each side of mantle, forming dark lines or narrow patches."

This natal down is soon replaced by the secondary down, which appears simultaneously with the fist downy plumage, very loose and soft in structure. A nestling about 6 inches long shows the first plumage appearing on the back, but the under parts are now covered with long, soft, "cinnamon-buff" down, tinged with grayish on the chest. A still larger nestling, about 10 inches long, is feathered on the back with the first plumage, "Verona brown" or "bister," broadly tipped with "cinnamon-buff"; the wings have just started to grow, but the tail has not yet appeared; the long, soft, thick down of the under parts is "cinnamon-buff," suffused with dusky on the chest and throat; the facial disks are now brownish black. The first winter plumage, which is much like that of the adult, soon begins to appear through the downy plumage, and the latter is gradually molted while the wings and tail are growing. By September or October, or perhaps earlier in early hatched birds, the young bird is fully clothed in a firm plumage, which is practically adult.

Adults have a complete, annual molt between August and November. Witherby (1924) says that a molt of the body plumage occurs between January and March. Although the manuals do not mention it, I have noticed that adult males, perhaps the oldest birds, average much paler in color than the females. Some of the old males have an almost pure-white ground color on the belly, only faintly cream-white on the breast, and pure white on the tibiae and under tail coverts; in these birds the light edges above vary from "cream-buff" to white. On the other hand, the darkest females are colored "ochraceous-buff" to "warm buff" on these parts. These differences may be color phases or partially due to age or seasonal changes, but there seems to be an average sexual difference.

T. Russell Goddard (1935), while studying short-eared owls in England, discovered "that there were two distinct colour forms. . .a brown form and a grey form. Of the six birds under observation during April and May three were brown and three were grey. They were paired in the following manner--two browns, two greys, and a grey male paired with a brown female. The grey form was literally a cold grey without any warm brown about it at all. The feathers on the breast and tarsi, which in the brown form are a warm buff, were white in the grey form. The grey form of the Short-eared Owl was, in fact, quite as cold in colour as the extreme grey form of the tawny owl (Strix aluco)."]

Food.--The short-eared owl is the friend of man, and if he had been treated as he deserved and not shot on sight--as is man's stupid and cruel habit--the damage to our young orchards by mice, now so common, would be less. Rodents of various kinds, particularly meadow or field mice (Microtus), which do so much harm, are his favorite food. Dr. A. K. Fisher (1893b) reports the findings in the stomach of 101 short-eared owls as follows: "1 contained small birds; 77, mice; 7, other mammals; 7, insects, and 14 were empty." Of the mice, nearly all were meadow mice, a few white-footed, pine, and house mice. Six shrews, a cotton rat, a rabbit, and a pocket gopher were the other mammals listed. A grackle, a red-winged blackbird, 4 juncos, 11 sparrows of various species, and a robin were the bird victims.

Junius Henderson (1927) states that 75 percent of the food of this owl consists of mice and that it is more insectivorous than any other of our owls except the burrowing and perhaps the screech owl. One stomach contained 50 grasshoppers, one 18 May beetles, and one 13 cutworms. Of 254 stomachs examined, 15 percent contained birds. Cahn and Kemp (1930) examined 137 pellets of this owl and found the remains of 110 small mammals of five species and of three birds; two were meadowlarks and one a vesper sparrow.

Errington (1932c) from a study of pellets found the remains of 68 meadow mice, 115 deer mice, 1 snow bunting, and 1 meadowlark, and he says that this owl "seemed to show a distinct preference for small mammalian over small avian prey, even at times when small birds may have actually far outnumbered the rodents which were depended on for food."

Although rodents are the chief of this bird's diet there are occasional exceptions generally under unusual circumstances. Thus William Brewster (1879) found at Muskegat a small colony of short-eared owls that preyed on the nesting terns. At least a hundred had been killed and eaten, judged from the remains, and in each case the breast had been picked clean, but nothing but the breast had been eaten. At this island in June 1913, I found about 50 terns treated in this way by the short-eared owls. Nothing but the breasts and entrails had been eaten. The remains of the terns were found singly or in groups of three to six. Laurence M. Huey (1926b) reports an entire California black rail, swallowed in two pieces, in the stomach of a short-eared owl. He also reports in detail the contents of two pellets of this bird from a salt marsh near San Diego. In one of these were the skulls and other bones of two species of bats and the remains of a meadow mouse, of a Belding's marsh sparrow, and of a Savannah sparrow. The other contained the remains of the two species of bats, of an American pipit, and unidentified bird bones, feathers, and mouse hair. Pierce Brodkorb (1928) reports two juncos and two swamp sparrows found in one stomach and in another a snow bunting. Urner (1923) found a nest of this owl "literally carpeted with the feathers of small birds. At its edge was a freshly-killed Sharp-tailed Sparrow. I found no remains of mice and only one small pellet composed apparently of feathers." Ludwig Kumlien (1899) found a nest in Wisconsin made up of feathers and matted grass in which he found the remains of more than 40 species of birds varying in size from a kinglet to a meadowlark and, curiously enough, no trace of any mammal. He took the three young, about two weeks old, to his house and found they required 12 to 15 English sparrows daily to satisfy them.

J. A. Munro (1918) records the following:

Between September 28 and October 16, 1909, I spent several days collecting in a small dry meadow, on the south shore of Ashbridge's Marsh [Toronto]. Short-eared Owls were more numerous than usual and were apparently feeding entirely on small birds. Four stomachs examined contained feathers and bird bones exclusively. In a small tract of dry grassy meadow, roughly estimated at fifty acres, I found feathers of the following species marking the spot where they had been eaten by owls; one Hermit Thrush, one Sora, three Yellow-bellied Sapsuckers, one Slate-colored Junco, one White-crowned Sparrow, and eighteen others, of which there were not enough feathers left to identify the species.

During April and the early part of May of the following spring, the owls were again plentiful, preying on the hosts of migrants that rested along the sandbar after crossing Lake Ontario. With one exception all the castings contained the bones and feathers of small birds. This meadow was swarming with voles, but only one pellet, of the many examined, was composed of the fur and bones of voles.

Ivan R. Tomkins sums up and draws interesting conclusions on the findings of pellets collected near Savannah, Ga., and examined by the Biological Survey. He says: "The 50 pellets collected during January and February contained remains of 34 birds, of 14 identifiable species, and 54 mammals, of two or more species. The 18 pellets collected in the same places during late February and March contained remains of 4 birds and 45 house mice. Several points of interest are: The unusual proportion of birds in the first lot (there was also an abundance of birds during the last period, but mammals seem to be the choice of food then) and the presence of such species as fox and white-throated sparrows, woodpecker, flicker, and kinglets, all species preferring thickets or woods, coupled with the absence of Savannah and song sparrows, these last very abundant in the precise locality most inhabited by the house mice and rats."

Behavior.--Owing to its diurnal habits and its love of open places the short-eared owl is one of the owls most frequently seen by man. It avoids forested regions, although in its extensive migrations it passes over them as well as over the sea and has therefore been observed on rare occasions in the midst of a forest or many miles at sea. William A. Bryan (1903) reported one that was seen to circle down from a great height and alight on one of the yards of a vessel bound for the Hawaiian Islands and 680 miles from Puget Sound. This was in October 1902. In the same month, in 1900, another was observed some 500 miles from these oceanic islands.

In hunting its prey the short-eared owl adopts the same habits as the harrier, or marsh hawk, and may often be seen circling close to the ground or flying over it, sometimes gliding, sometimes flapping and dropping down on its victims with down-stretched feet. Occasionally it sustains itself by hovering over one spot before it pounces. When the wind is blowing strongly, it takes advantage of the up-currents over rolling county especially among sand dunes, where it may be seen gliding into the wind with great speed and skill. At times it may be seen sailing lightly about at a height of 20 or even 30 yards, turning its round head now this way now that and closely scanning the ground. On some occasions it alights on the ground and watches for its rodent prey to appear. R. H. Lawrence (1892) reports that in the salt marshes near South Bend, Wash., "they sat much on the edges of many deep sloughs waiting for a species of rat. I found many evidences of their success in getting them." There is a cut in the Argentine ornithological journal, El Hornero, of one of these owls sitting on the ground with its feet on either side of a mouse hole, ready to clasp its victim should it emerge from the ground.

The short-eared owl may often be found perched motionless on fence posts or stubs of trees, in tufts of grass, or even on the bare ground. Here among dead grass, especially in sand dunes, it is very difficult to see. On one occasion after being deceived several times by owls that resembled stumps or small posts flecked with lichen or sand or snow, I was willing to consider a certain obvious stump to be an owl, but after changing my mind and deciding it was not one, the "stump" opened its wings and flew away! In such situations, the owl remaining perfectly motionless until the fatal moment, doubtless snaps up many a wandering mouse.

Although this owl hunts freely by day it hunts more freely at dusk and in the early dawn, and it also hunts at night. It sleeps at intervals both day or night usually concealed in tufts of grass and sometimes in thick evergreens, in the latter no doubt in storms. In walking over an upland pasture or marsh, or among sand dunes, one may suddenly flush a short-eared owl, disturbed from its nap or watching for a victim, or feasting on one already killed. Once I flushed one in dunes that, judging from the many feathers about, had been eating a robin. At such times the owl flies away, sails gracefully about, and often alights again at no great distance.

Charles A. Urner (1923) reports the following interesting behavior of a short-eared owl. After he had answered the call of a yellowlegs--

Suddenly a Short-eared Owl came out of the growing darkness and dove at my straw hat. He missed it by inches. I whistled the Yellow-legs call again. He turned and dove at me a second time with no end of determination in his manner. Six times I whistled and six times he turned and swooped at me, finally alighting on a mud pile nearby to look the situation over more carefully. I stood in the open marsh with no protection. Had I whistled in the daylight he would have shown no interest. Apparently he did not recognize me as a human in the dusk. He struck on the impulse of his ears--not his eyes. And apparently he knew the taste of Yellow-legs.

Short-eared owls may be seen pursuing crows and even marsh hawks. Eugene Bicknell (1919) watched a pair of owls repeatedly attacking a single crow. "The Crow, perhaps to escape the Owls, perhaps intent on depredation of their nest, several times swept down to the ground about a certain spot, the Owls pursuing it or awaiting its return into the air when attack and counter-attack were renewed. The following year at the same place a pair were observed on February 22, attacking a Marsh Hawk."

In the following incident the tables were turned against the short-eared owl as reported by H. P. Attwater (1892). He was attracted by cries of two red-shouldered hawks and, walking toward them, flushed three or four short-eared owls. "One in particular mounted to a great height, followed by the Hawks, and in the fierce attack which followed it held its own bravely for some time till they finally appeared tired of the fight and flew away."

This owl sometimes attacks large birds, possibly only in a spirit of mischief or play and not with any intention of killing them. Thus William Brewster (1925) reports one swooping at black ducks in a pond, and another soaring in circles above a soaring great blue heron and swooping at and striking it repeatedly on the back. For several minutes this performance went on, the heron circling and "croaking incessantly and, when struck by the Owl, squalling so lustily that it might have been heard half a mile away. Quite evidently it was badly frightened. The Owl, without doubt, was merely amusing himself."

Clarence S. Jung (1930) describes an aerial fight between a short-eared owl and a marsh hawk. "The Owl pursued the Hawk, flying above the retreating bird. Hovering some ten feet above the Hawk, the Owl would suddenly swoop down in a fierce attack. In the same instant the Hawk would half turn like a tumbler pigeon, in such a manner so as to strike the Owl with its talons as that bird passed. The dexterity and maneuver of the two birds was amazing. The attack was repeated seven or eight times. It is to be supposed that the Hawk disturbed the Owl's nest and was being driven away."

Voice.--During migrations and winter the short-eared owl is one of the most silent of birds, but on the breeding grounds especially when the young are about it is far from silent. The courtship song, both vocal and instrumental, has already been described above. Charles A. Urner (1923) describes five distinct calls of the short-eared owl. The first, high pitched and rasping, resembles the barking of a small animal. It is usually uttered in triplets and might be written wak, wak, wak or yak, yak yak, but there may be eight or more rapid repetitions. The second is uttered singly and is more prolonged, w-a-a-a-k. The third, Mr. Urner writes as wa'u or even wow. The fourth suggests sawing or filing, a rather long drawn rasping note, while the fifth is a clear whistle-like squeal. Like most owls, young and adults may snap their bills and hiss. Saunders (1913) states that the voice of the female is "higher pitched, more squeaky and less harsh than the male." The cries of the owls, especially when their young are disturbed, have been likened to the "squealing of young pigs" and to "the barking of a young puppy" (W. W. Worthington, 1893). Lawrence (1892) says "this owl has a shrill barking call like the 'Ki-yi' of a little dog." Mabel Densmore (1924) describes the notes of a pair of birds signaling to their nearly fully grown young as "subdued noise, muffled and short, half sneeze, half bark" and that of the young like the sound of "escaping steam turned on and off suddenly but lasting about three seconds."

Field marks.--As the short-eared owl skims the marshes and fields like a harrier, it might be mistaken for a marsh hawk, but the much shorter tail and the large round owl head, as well as the absence of white on the rump, make its identification easy. The small "horns" or "ear-tufts" cannot be seen in flight and only rarely when the bird is perched. They are so short that they are concealed when the bird is alarmed or excited and erects the feathers of the head. The light under parts of the bird and the small oblong black patches at the base of the primaries seen from below are good field marks. It is about the size of the broad-winged hawk from which it is at once distinguished by its round head. A patch of creamy brown on the upper surface of the open wing is also distinctive.

Winter.--As small rodents are the favorite food of this owl, it generally migrates south to grassy and weedy regions where there is little or snow. In such favorable localities they sometimes collect in considerable numbers. Harris (1919) describes such gatherings in flocks of 8 to 50 in the prairies close to buildings in Kansas City and Tyler (1913), in the Fresno district of California, estimated as many as 200 of these owls hunting over stubble fields at sunset one December afternoon.

Frank L. Farley contributes the following note: "In the fall of 1931, when engaged in threshing their grain, farmers in central Alberta noted an unprecedented number of mice in the fields. Later, when winter set in and threshing operations were halted on account of deep snow and extreme cold, it was discovered that the grain shocks in the fields were infested with the rodents, as many as a dozen of the destructive little animals having taken up their winter quarters under a single shock. In October and November, unusual numbers of short-eared owls were observed patrolling the fields, hunting for mice, and later their numbers were augmented by the arrival of thousands of northern-bred birds. On December 31, 1931, H. A. MacGregor and I drove 25 miles by automobile, south of Camrose through the Duhamel country, and saw 24 of these owls. All were hunting in, or adjacent to, fields of shocked grain. John W. Russell recorded in 16 days, between November 26, 1931, and February 5, 1932, 116 owls, this being at the rate of 7.25 a day. The number of mice that this vast army of owls destroyed must have reached enormous proportions, and the birds may have prevented what otherwise would have resulted in a serious plague. An invaluable service was rendered at a time of emergency, and at no cost whatever to the people."

The short-eared owl is an interesting and beneficial bird. May it long survive!

Short-eared Owl* Asio flammeus

*Original Source: Bent, Arthur Cleveland. 1938. Smithsonian Institution United States National Museum Bulletin 170 (Part 2): 169-182. United States Government Printing Office