There are three subspecies of Merlins in North America that differ in appearance. The Black Merlin occurs in the Pacific Northwest, the pale Prairie Merlin in the northern U.S. and southern Canada, and the Taiga Merlin in far northern forests. Black Merlins are largely sedentary, while Prairie Merlins and especially Taiga Merlins are migratory.
Powerful and rapid flyers, Merlins are skilled aerial hunters. During the nesting season males may spend up to 70 percent of their time hunting, but during the winter over 90 percent of their time is spent perching. Besides small birds, Merlins also capture dragonflies for food.
Description of the Merlin
The Merlin is a small, fast falcon of open country and open woods. Different races all have similar plumage features including vertically streaked underparts and a faint moustache below the eye, but the upperparts can vary from light to dark overall. Its wings are short and pointed, and its flight is usually direct and fast.
Males have bluish to blackish upperparts and tail, depending on race.
Females have pale brown to dark brown upperparts, depending on race.
Seasonal change in appearance
Juveniles resemble adults.
Merlins inhabit open prairies, open woods, and marshes.
Merlins primarily eat small birds, but also large insects and rodents.
Merlins often hunt from perches, or by flying low to flush potential prey.
Merlins breed from Alaska south to the northern U.S. Rockies, and winter across most of the central plains and Atlantic and Pacific Coasts. The population appears to have increased in recent decades.
Most of the Merlin’s prey is captured in midair, utilizing fast and agile flight.
Male Merlins deliver food, but the female feeds the young.
The typical call is a rising and falling series of harsh notes.
The Merlin’s nest is usually an old crow or hawk nest, or a cliff ledge or tree cavity.
Number: Usually lay 4-5 eggs.
Color: White with darker markings.
Incubation and fledging:
The young hatch at about 28-32 days and first fly at about 4 weeks.
Bent Life History of the Merlin
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 Merlin – the common name and sub-species reflect the nomenclature in use at the time the description was written.
FALCO AESALON AESALON TunstallCONTRIBUTED BY FRANCIS CHARLES ROBERT JOURDAIN
The claim of the merlin to a place in the American list rests, according to the fourth edition of the A. 0. U. Check-List, on the fact that it is “accidental in Greenland.” The latest and best authority on Greenland birds is the monumental work “Danmarks Fugle”, initiated by the late E. Lehn Schiller, of which the third volume, dealing with the Raptores, was completed with the help of R. H0rring, H. Scheel, and A. Vedel Taning. Here two races of the merlin are recognized from western Europe, the typical race (which most European ornithologists regard merely as a form of the pigeon hawk, F. columbarius, and which, according to the A. 0. U. Check-List, should be called F. aesalon aesalon Tunstall) and the Icelandic race (F. aesalon eubassalon Brehm). As the nearest point of the Iceland coast is only about 300 miles distance from east Greenland, while the Shetlands are at least 1,300 miles away, it would seem probable that stragglers to the Greenland coast would belong to the Iceland form, if recognizable. This is not the place for an analysis of the distinguishing points of the two races, but, on the measurements given in “Danmarks Fugle”, the Iceland bird is the larger, the wing of Icelandic males measuring 209.7 mm (average), females 228.9 mm, while Scandinavian birds average 197.8 mm (males) and 213.6 mm (females), and Faeroe birds are intermediate, the males averaging 200 mm and the females 221.7 mm. According to Kleinschmidt, who pointed out the difference between the Icelandic and European forms and proposed the name Falco alfred-edmmundi for the Iceland bird in 1917, there is also a difference in color, the Icelandic bird being darker. In Schi0ler’s work details are given of about four American occurrences: One at sea, south of Greenland, in May 1867; another at Cape Farewell on May 3,1875; one near Christianhaab on July 1, 1883 (?); and one for Angmagsalik, July 3, 1914; with another possible occurrence in 1q08. The early records were ascribed to the Scandinavian form, but the distinctness of the Iceland race was not then appreciated; the Angmagsalik bird must be definitely classed as Icelandic (if recognized), as its wing (female, juvenal) measures 228 mm and the culmen 15 mm.
In the following notes no attempt has been made to separate those referring to the Icelandic form from those applicable to the typical race.
In Iceland the merlin is a summer resident, arriving about the end of March or the beginning of April, but in the Faeroes and the British Isles it is mainly a resident, although many, probably including most of the birds of the year, move southward in autumn and may be met with in districts where the species is never known to breed.
It is a bold and dashing little falcon and has no hesitation in attacking birds larger than itself, such as the golden plover and lapwing, but its normal prey consists of small birds, such as the meadow pipit (Anthus pratensis) and the other small passerine birds that are to be found on the outskirts of the inoorlands. In Iceland there is little cultivation, and here the merlin is by far the commonest raptorial bird, though nowhere numerous. In this treeless land of lava fields and moors one comes occasionally on a pair that has selected a breeding site, generally on some rocky outcrop or cliff, but at times also among the scanty heather on the ground. In the Shetlands and Orkneys it is also the commonest of the Accipiters and may be met with almost anywhere, not only on the tops of the hills, but also, as Saxby (1874) has well described, in the marshes and on the cliffs or by the shore, while it includes in its hunting grounds the roofs and chimneys of the villages and may dart down upon a sparrow or a lite even at the very door of a house.
Farther south, on the mainland of Scotland and the moors of northern England, its home during the summer months is on the hills, where it may be seen perched on a rock or swiftly flying over the rough pastures and heaths, beating the countryside with untiring zeal until some luckless small bird is flushed and flown down. Here its nest is usually to be found in or near the same spot year after year. Seebohm (1883) gives details of two sites on the Yorkshire moors for five years. During this period, on several occasions, both male and female were shot by keepers at the nest, and the young or eggs destroyed. Yet the next year, or sometimes after an interval of a year, another pair of birds appeared and recognized the old site. To anyone living on a grouse moor in northern England, it seems almost incredible that the stock can be kept up, for the breeding places are known by tradition to the keepers and it is only occasionally that a pair manages to bring off a brood from some remote part of the moor. Where the birds came from to replenish the vacant sites was long a mystery, for though the merlin does little real harm on a grouse moor, no keeper will ever allow this beautiful little falcon to hatch off, if he can possibly prevent it with the help of a trap or a cartridge or two. Fortunately for ornithology, there are, however, large tracts of hills, covered chiefly with rough pasture and a little heather and bracken, which are practically valueless as far as grouse are concerned and so do not come under the keeper’s jurisdiction. Often these bills are on the edge of the industrial districts of Yorkshire and Lancashire, and the numerous tall factory chimneys, which disfigure the valleys, make the place look most unlikely as a breeding haunt for a falcon, yet it is here that the merlin has found sanctuary, and it is from these my promising-looking surroundings that the annual output of young birds moves south every year to return to the historic sites on the grouse moors, where so many of their relatives have died. There is no part of the British Isles where merlins may be found nesting in fair numbers in such restricted areas, as this “no man’s land.”
South of the Trent the merlin is only an autumn and winter visitor to the midland and southern counties, except among the hills of Wales and on Exmoor. Here a certain degree of variation in the breeding site begins to be apparent. In the northern part of its breeding range there are no trees, and it must breed among the heather or on the rocks. There are a few cases on record in Scotland and northern England where it has bred in an old nest of a hooded or carrion crow, but in Wales this habit becomes quite common, and on Exmoor the pair or two that still breed prefer to use an old nest in a tree or stragling hedge. Another site adopted by Welsh merlins is among sand dunes overgrown with marram grass. Here in a little cup scratched out in the sand and lined with grass, the merlin has found a new type of nesting place.
Courtship: Little is on record on the coursthip of the merlin, but like so many other Accipiters, both male and female describe aerial evolutions high in the air over the nesting site at the beginning of the breeding season and especially on warm sunny days. At other times the merlin does not fly high. William Rowan (1921: 22), who has described the breeding of the merlin on the Yorkshire moors very fully, did not observe any aerial courtship but suggests that the feeding of the female by the male at the nest site may be part of the ceremony and is frequently followed by sexual union.
Nests: In the foregoing remarks something has already been said as to the different types of sites adopted by the merlin in different surroundings. Little actual nest is made. When in heather or on rocks it is little more than a hollow in the ground with a few heather twigs artlessly arranged, but grasses may be pressed down if already present. When an old nest of some other species, crow or raven, is used, practically nothing is added to it. On the sand dunes the marram grass is formed into quite a passable nest. Rowan (1921: 22) noted that, during the early stages of incubation, the bird would break off twigs from heather within reach and add them to the nest.
He also noted bits of bracken in a nest when a patch was within easy reach.
A very extraordinary site is recorded by Nordling from Finland, in a weatberworn and old hole of a woodpecker in a tree. In the wooded parts of Scandinavia and Finland, an old nest in a birch or pine is frequently used, although beyond the tree limit, only cliff and ground sites are available. It seems to be an almost invariable rule that a nest on the ground should command a good view of the adjacent country.
Eggs: The commonest number of eggs in England is four, and five are quite exceptional. Farther north the proportion of fives seems to increase, and in the Orkneys and Iceland they are common enough. The six set has occurred in Scotland at least nine or ten times and probably oftener, while seven occur in Sweden in lemming years and have also been recorded from Finland. Six have also been recorded from Iceland. Second layings may consist of only three eggs, but E. R. Paton (1917) says that it is also found in first layings at times, and J. A. W. Bond confirms this.
In color they show less variation than the kestrel’s eggs, and they are sometimes rather elongated in shape, but normally almost oval, the creamy ground being often quite concealed by red-brown stippling and spots. It is rare to find a really richly and boldly marked clutch, and the most remarkable varieties are those in which most of the coloring matter is absent and a good deal of the creamy ground is visible. One remarkable set has three eggs almost white, while the fourth is clouded with red-brown. Other varieties show patches of violet shell marks, while some sets have a very attractive violet bloom, and others are of a pale yellowish type, approaching that of the hobby (F. subuteo). All the eggs are rather dull, and those from the moors near industrial centers become much contaminated by soot in the air.
Measurements of 100 British eggs average 39.95 by 31.27 millimeters; the eggs showing the four extremes measure 42.4 by 32, 41.4 by 33.8, 37 by 29.1, and 40.3 by 29 millimeters. Fourteen Icelandic eggs average 40.9 by 31.9 millimeters; the eggs showing the four extremes measure 42.3 by 32.8, 41 by 33.2, and 38.9 by 30.2 millimeters.
Young: : The eggs are laid at 48-hour intervals, i. e., every second day, and Paton (1917) states that in a clutch of three it begins with the third egg; other observers are of the opinion also that it begins on the completion of the set. Both sexes take a share in incubation, but there seems to be a consensus of opinion that the female takes the greater share of the work. Rowan (192 1: 22), however, states that in one case where he watched at night the male was incubating all the time. During brooding the hunting is done by the male, the hen generally keeping to the neighborhood of the nest, while she preens and sleeps during her mate’s spell of brooding.
The incubation period is estimated by Rosenius at 25 days; Edmondson states that it is not less than 26 days, while Rowan says that three eggs hatched on the twenty-ninth day, and Paton gives 30 days (minimum 29.) On the whole I think about 29 days would be a fair average. In a case recorded by H. S. Gladstone (1910) hatching was spread over 3 days, so probably in this case incubation began before the clutch was complete.
The young are fed by the female, who leaves her station and takes the prey from the male, not at the nest, but generally at or near one of the perching places in the neighborhood. The young remain in the nest for 25 to 26 or 27 days but stay in the vicinity for some time longer. Only one brood is reared in the season.
Plumages: The plumages are fully described in Witherby’s Handbook (1924, vol. 2, pp. 116: 118) and need not be repeated here at length. The male is readily recognizable by his slaty-blue upper parts, while the tail has a conspicuous broad black band; the hen is not unlike a hen kestrel but lacks the reddish-brown color, which is replaced by brown in which the red is lacking. The flight, however, is quite different: low, eager, and dashing.
Food: The food of the merlin consists almost entirely of small passerine birds, very largely meadow pipits, but also occasionally skylarks, twites, linnets, yellow buntings, ring ouzels, and song thrushes, while over 20 other species have been recorded from time to time. Besides these small birds up to the size of the mistle thrush and starling, downy young of grouse are known to be taken at times, but only in the very early stages, and larger birds, such as the smaller waders, and even the golden plover, lapwing, rock dove, and lesser tern have been recorded as taken. Mammals (voles and one record of rabbit), insects in small numbers, and lizards complete the bill of fare.
Behavior: Although so small a bird, the merlin is extremely bold. Dr. H. L. Saxby (1874) says of it: “I have repeatedly seen it, with rapid swoops and loud menacing cries, send a cat sneaking home from under a hedge, and I once saw it openly attack a full grown Hooded Crow; only desisting when, attracted by the outcry, two old ones came hurriedly to the rescue. * * * More than once I have known it to seize a newly shot golden plover as it fell, and although unable to lift it many inches from the ground, and constantly compelled to drop it, make such good use of its opportunity as to he far beyond reach with it by the time the shouting and gesticulating shooter, having reloaded, was at liberty to follow in pursuit.” J. G. Millais (1892) also once saw a merlin dash at a black cock and send it sprawling. Saxby (1874) also says that it is very easily tamed and becomes a most docile and intelligent pet. One that was allowed full liberty could be instantly recalled by waving about in the sunlight a tin basin in which its food was usually kept.
Voice: This has been very well and carefully described by Rowan (1921: 22). First of all there is the alarm note, a rapidly repeated keic-keic-kek, not unlike that of the kestrel. In the cases that came under Rowan’s observation, the note of the cock was higher pitched than that of the hen, and readily recognizable. The feeding note of the male closely resembles the alarm note but is repeated only half a dozen times and more rapidly than when alarmed. The hen responds to this with her feeding note, a characteristic, long-drawn and oft-repeated eep-eep-eep, which she keeps up for some minutes continuously. Rowan also records a soft tick, uttered when alighting at the nest, by both sexes. The hunger call of the young somewhat resembles the food cry of the hen, but it is not so loud and is repeated more quickly.
Enemies: The one real enemy of the merlin is the keeper, but with little reason, for the grouse live on good terms with it, and it is only for a very brief period in the season that the chicks are ever taken.
Breeding range: Falco aesalon subaesalon breeds in Iceland, an intermediate form in the Faeroes, and the typical race in the British Isles (Scotland and its islands, northern and southwestern England, Wales, and Ireland), Norway, Sweden, Finland, northern and middle Russia, and western Siberia. Other races breed in southeastern Russia (F. a. pallidus), and in Asia, from Turkestan to Japan (F. a. insignis).
Winter range: Faeroes and British Isles, migrating from northern Europe through middle Europe to the Mediterranean region, wintering commonly in northwestern Africa (F. a. aesalon) and in Egypt (F. a. insignis). Asiatic birds winter south to Turkestan and northwestern India.
Migration: The Iceland bird has recently been proved to visit the British Isles, a banded bird having been obtained in Kings County, Ireland. The four, or perhaps five, American records have already been mentioned. A juvenile bird has also been recorded as far south in Africa as Natal (Ibis, 1920, p. 508). In the Arctic region it has been recorded as a casual oft Bear Island, and it is a common passage migrant in Novaya Zemlya, where it may possibly breed.
Egg dates: Of 34 dates from the British Isles, ten fall between May 9 and 15, seven between May 16 and 22, and eleven between May 23 and 29; of June dates (first to twenty-first) there are six, but one on June 6 was much incubated, and one on the twelfth a second laying, while that on the twenty-first was probably also a second laying. Four Iceland dates fall between May 20 and June 12, while seven dates from Finland fall between May 30 and June 25.
EASTERN PIGEON HAWK
FALCO COLUMBARIUS COLUMBARlUS Linnaeus
Oar American merlins, or pigeon hawks, have been subdivided by the latest authorities into four races. There are three quite distinct forms, but one of these, suckleyi, may be only a color phase, as it seems to have no distinct range in which it alone is found; and the fourth, bendirci, is to my mind only an intermediate between the darker and the lighter races, and is too near the eastern race to warrant recognition. This matter is discussed further under these two forms. The range of the eastern form extends roughly north to the limit of trees and west to the eastern edge of the prairie regions and to Alaska. Some form of the pigeon hawk is to be found at some season of the year over practically all the North American Continent, except in the treeless Arctic region.
Spring: To most of us the pigeon hawk is known only as a spring and fall visitor, as its breeding range is mainly north of the United States and as it spends its winters in the Southern States and beyond our borders. In New England the spring migration occurs mainly during the last half of April and the first half of May, coinciding with the main flight of small birds on which it feeds.
Nesting: My experience with the nesting habits of the pigeon hawk has been limited to two nests found on the south coast of the Labrador Peninsula and one found in Newfoundland. In each case our attention was attracted to the nesting site by the noisy behavior of the birds, flying about nervously and screaming excitedly even while we were some distance away. On June 3, 1909, while we were walking along the rocky shore of Eskimo Island, Canadian Labrador, we heard the cries of a small hawk; on climbing up to the edge of the spruce woods, we saw a pigeon hawk flying about, or perching on the top of a tall spruce and flying down occasionally into the woods. I began a careful search through the dense thickets of spruces and firs, where I finally found, in a thicket of taller spruces, what looked like an old crow’s nest, about 14 feet up in a red spruce. The hawks were not in evidence, but I climbed up to the nest and was surprised to find three beautiful eggs. It had long been my hope to collect a set of pigeon hawk’s eggs, and four days later I returned and gratified the wish by taking a handsome set of five eggs and photographing them in the nest. The nest was apparently a very old crow’s nest that had since been used by red squirrels, as the deep cavity had been filled with rubbish, including numerous seed scales from the cones of the white spruce. It rested on horizontal branches close to the trunk of the tree and was made of rather large, dead sticks, interwoven with soft mosses; the center had been hollowed by scraping out the rubbish, which had become quite rotted; very little lining had been added, merely a few small pieces of fine twigs and lichens; a few bits of down were visible in and around the nest and on the surrounding branches. The nest measured 16 by 14 inches in outside and 8 by 8 inches in inside diameter; the outside height was 9 inches and the inner cavity was ~ inches deep (pl. 16).
‘While fishing for trout in the Mingan River, on June 17, 1909, we were attracted to another nest by the cries of a pair of pigeon hawks. This was somewhat differently located in a large, rather open space in heavy spruce timber, where there were a few tall, scattered spruces. My companion, Dr. Charles W. Townsend, saw the male falcon fly into a tall black spruce and out again, in which a large nest was visible; he rapped the tree and the female flew from the nest. The tree was about 45 feet high and measured 58 inches in circumference near the base, a very large tree for this region. The nest was about 24 feet from the ground and 10 inches out from the trunk on a horizontal limb, well sheltered from above and on the north and east sides by thick foliage. It was apparently a new nest, made of dead sticks and lined with masses of soft, fine rootlets, a few small twigs and pieces of bark, and a few feathers. It measured 20 by 15 inches in outside and 9 by 8 inches in inside diameter; it was hollowed to a depth of 2 inches and was only 5 inches high over all. The four eggs that it contained had been incubated for about a week.
My third nest was in an entirely different situation, and we were puzzled for a long time to find it, although the hawks advertised it in no uncertain terms. On June 19, 1912, while we were hunting around Gaiftopsail in Newfoundland, a pigeon hawk flew out from a large tract of heavy spruce and fir woods, yelling and showing every sign of anxiety. But, though I searched those woods thoroughly for over an hour, no occupied nest could be found. Meantime, my guide, who was sitting out on an open hillside to watch the birds, saw the male falcon hover for an instant over a little hummock on the hillside. As he walked toward it the female flushed from her nest when lie was about 100 yards from it. The nest, containing five eggs, was on the ground in a roomy hollow under some low, scraggly firs and spruces only a few inches high (p1. 17). The hollow was lined with bits of twigs and a few feathers.
I heard of two other cases where these falcons had nested on the ground in that vicinity. Also, out of seven sets of pigeon hawks’ eggs in W. J. Brown’s collection, three of them were taken from nests on the ground, all from this same general region. He also refers, in his notes, to a nest found in Matane County, Quebec, that was about 50 feet up in a spruce tree.
Dr. Harrison F. Lewis (1922) writes:
On June 22, I found, a few rods west of the first falls of the Little Natasliquan River, a rather unusual nest of this species. It was on the ground, among the Reindeer lichen, on the summit of a small knoll of gentle slope. A black spruce “tree” which had grown here for many years, until it had attained a height of about 3 feet and a width of 6 feet, had died, apparently two or three years previously, leaving a confused snarl of stiff dead limbs. The Pigeon Hawks had placed their nest beneath this shelter. The nest, which was about 6 inches across and 1 inch deep, was a depression in the soil, here composed of sand and rotten wood, and was lined with a few small scales of bark, picked by one or both of the Hawks from the base of the trunk of the sheltering “tree,” as was clearly indicated by the recent scars on that trunk. Four eggs rested on these bits of bark. One Hawk flew from the nest when I approached it, and it and its mate scolded me vigorously, charging repeatedly to within a few feet of me, as long as I remained in the vicinity.
Dr. Lynds Jones wrote to Major Bendire (1892) “that he found a nest of this species near Grinnell, Iowa, on April 28, containing four eggs. They were placed in a hole in an American linden tree about 8 feet from the ground. The nest was made of dry grasses, fibrous bark, and a few feathers.”
Roderick MacFarlane (1891) writes:
This falcon ranges along the Anderson River almost to the Arctic coast of Liverpool Bay. Several of their nests had apparently been built by them on pine trees, and others on the ledges of shaly cliffs. The former were composed externally of a few dry willow twigs and internally of withered hay or grasses, etc., and the latter had only a very few decayed leaves under the eggs. * * * I would also mention the following interesting circumstance: On the 25th of May, 1864, a trusty Indian in my employ found a nest placed in the midst of a thick pine branch of a tree at a height of about six feet from the ground. It was rather loosely constructed of a few dry sticks and a small quantity of coarse hay. It then contained two eggs. Both parents were seen, fired at, and missed. On the 31st he revisited the nest, which still held but two eggs, and again missed the birds. Several days later he made another visit thereto, and to his surprise the eggs and parents had disappeared. His first impression was that some other person had taken them. After looking carefully around, he perceived both birds at a short distance, and this led him to institute a search which soon resulted in finding that the eggs must have been removed by the parent birds to the face of a muddy bank at least forty yards distant from the original nest. A few decayed leaves had been placed under them, but nothing else in the way of lining. A third egg had been added in the interim. There can hardly be any doubt of the truth of the foregoing facts.
H. Kirke Swann (1936) states that the pigeon hawk sometimes nests “under the roofs of deserted buildings.”
Eggs: The number of eggs laid by the pigeon hawk is usually four or five, oftener five than four, very rarely six, and occasionally only three. They vary in shape from short-ovate to oval or nearly elliptical-ovate. The shell is smooth but without gloss. They look almost exactly like small duck hawks’ eggs, showing the same rich and brilliant colors, but they average somewhat darker. Bendire (1892) describes them very well, as follows: “The ground color when visible is pale creamy white as a rule, and is hidden by a reddish brown suffusion of various degrees of intensity, and this, again, is finely marked or boldly blotched, with different shades of burnt umber, claret brown and vinaceous rufous. These markings are generally equally and profusely distributed over the entire egg, and are superficial; occasionally they are most distinct about one of the ends, being disposed in the shape of a wreath.”
I have seen some that were sparingly spotted with dull browns and buff; and one set that was nearly immaculate white. The measurements of 55 eggs average 40.2 by 31.3 millimeters; the eggs showing the four extremes measure 44.5 by 3a, 40.4 by 33.1, 37.5 by 33, and 38 by 39 millimeters.
Plumages: When first hatched the young pigeon hawk is rather thinly covered with short, creamy-white down, mixed with pure white; this is replaced later by longer down, brownish gray or grayish white above and nearly pure white and longer down below. In a young bird, 18 days old and nearly fully grown, the primaries have begun to burst their sheaths and are about 1 inch long; the tail feathers are in about the same condition, but are only about three quarters of an inch long; the head and body are still wholly downy, except that feathers are appearing on the scapular region.
In fresh juvenal plumage, the crown is “russet”, broadly streaked with black; the mantle is “bone brown” to “clove brown”, with narrow “russet” edgings, and with a purplish sheen; there are some tips and concealed spots of “orange-cinnamon” on the scapulars and remiges; the tail is black, or slightly brownish, with narrower gray bars than in the adult, and broadly tipped with “pinkish buff”; the under parts are “cinnamon” to “cinnamon-buff”, broadly streaked, except on the chin and throat, with “sepia” or “bister.”
The sexes are alike in this plumage, which closely resembles that of the adult female. This plumage is worn for nearly a year with no change, except by wear and fading. By late in winter or early in spring the upper parts have faded out to “olive-brown”, “buffy brown”, or even “drab”; and the under parts are white, or creamy white, streaked with “snuff brown”, or even paler browns.
In April or May, when the bird is less than a year old, the molt into the adult plumage begins; the body plumage is molted first and the wings and tail later. I have seen molt in the wings in June, but usually it does not begin until July. The complete molt may not be finished until November.
In adult plumage the sexes are quite different. In the male the upper parts are “plumbeous”, darkest on the upper back; the tail is mainly black, tipped with grayish white, and with broad “cinereous” bands; the streaks on the under parts are black, or nearly so. The female is brown above, uniform “warm sepia” to “bister”; the tail is “olive-brown” to “clove brown”, with narrower, pale buffy bars; and the streaks on the under parts are “sepia.”
The annual, complete molts of adults are irregular and prolonged, much as in the young birds. Witherby’s Handbook (1924) says, of the European merlin, that the complete molt begins with the wing feathers in June and is completed usually in November, but sometimes not until December or even January. It also says that “what certainly appears to be a second moult confined to body feathers takes place Feb: March and occasionally not finishing until April.” It seems to me that this merely shows that the body molt precedes the wing molt. I once collected a breeding pair of pigeon hawks on June 17; the male was in fully adult plumage, but the female was mainly in immature plumage, much worn, and was molting the body plumage and the wings. This shows that sometimes at least these falcons, like some other hawks, become sexually mature before they acquire the adult plumage. This female had laid a set of four fertile eggs.
Food: T he pigeon hawk is mainly a bird eater. Dr. A. K. Fisher’s (189Th) report on the contents of 56 stomachs says that 2 contained poultry, 41 small birds, 2 mice, and 16 insects. The following birds have been recorded in its food: Leach’s petrel, green-winged teal, woodcock, snipe, sandpipers, Eskimo curlew, plovers, small domestic chickens, California quail, ptarmigans, pigeons, doves, chimney and black swifts, flickers, jays, bobolink, meadowlark, blackbirds, gracldes, various sparrows, waxwings, swallows, warblers, vireos, gnatcatchers, brown creeper, nuthatches, kinglets, pipit, robin, and thrushes. Other things listed include pocket gophers, squirrels, mice, bats, toads, lizards, snakes, dragonflies, butterflies, moths, grasshoppers, crickets, beetles, spiders, crawflshes, scorpions, and caterpillars. That this little falcon is able to catch such rapid fliers as swifts and swallows, or such nimble insects as dragonflies, speaks well for its powers of flight.
Its boldness and courage are shown in its attacks on the larger species. It has been known to enter a pigeon cote and kill and carry off a pigeon.
Dr. Fisher (189Th) says that “pigeons, flickers and grackles are about as large birds as it usually attacks, though Dr. Dali in one instance saw it kill a ptarmigan, and Dr. E. A. Mearns speaks of a specimen shot in the act of destroying a hen.” John Murdoch (1877) mentions four pigeon hawks that came out to a vessel in the Gulf of St. Lawrence: “The first that appeared had a Leach’s petrel, dead, in his talons. He alighted with this, on the fore crosstrees, and proceeded to eat it.” Dr. Elliott Coues (1861) saw one of these hawks, at Henley Harbor, Labrador, “foraging among the immense flocks of curlews (Numenius borealis), which then covered the hills in the vicinity.”
Thomas Mcllwraith (1894) once saw one dash into a flock of blackbirds; “how closely they huddled together, as if seeking mutual protection, but he went right through the flock and came out on the other side with one in each fist.”
Dr. B. H. Warren (1890) writes: “Two Pigeon Hawks during the late fall lurked about the southern suburbs of the borough of West Chester, preying at regular intervals on the pigeons of a blacksmith. In one week the hawks killed or drove away fifty of the birds. The hawks would enter the boxes and take from them the pigeons.”
Edward H. Forbush (1927) says of its hunting:
It likes to take a stand on post, pole or tree where, having an unobstructed view, it can survey at leisure the wild life of the locality, and from which it can launch forth in swift pursuit of some passing bird, or plunge into some near-by thicket after some timid warbler or sparrow. I never saw one descend almost perpendicularly from a great height upon its prey, as the Duck Hawk often does, and I have not seen one actually strike it prey. Its usual method is to chase the prospective victim, which in most cases it can overtake with apparent ease; but in my experience it is frequently baffled by the sudden doublings of the pursued, until it gives up the chase or the hunted bird escapes by suddenly diving into water or dense shrubbery. I have seen a Pigeon Hawk chase a small flock of Common Terns without even touching one, and once in Florida I watched one pursuing for a long time a flock of Sandpipers, but it was unable to catch one as long as the chase was maintained within my field of vision. The hawk seemed to be able to overtake them and to follow their flash-like turns quite closely, but could not lay its claws on a single bird; snipes and sandpipers continually escape, and probably the hawk cannot often take a vigorous shore bird in full possession of its faculties, but a weak, sickly or wounded bird would stand little chance before it.
Dr. Charles W. Townsend (1930) says:
I was watching, at Plum Island, a flock of twenty-one Semipalmated Sandpipers and a few Sanderlings, when they suddenly rose and flew off from the beach, close to the water, pursued by a falcon. Suddenly the falcon shot up for about ten feet into the air, banking with its wings and tail widely spread, then darted down with a splash into the water, submerging its outstretched legs, its belly and part of one wing. Rising with a sandpiper in its talons, it flew to an old stump washed up on the shore where it proceeded to tear out the breast and wing feathers of its victim.
This is what we saw but it is evident that it had struck down the sandpiper in flight so quickly that our eyes failed to follow, and had immediately turned to pick it up. The victim was a Semipalmated Sandpiper and the falcun a Pigeon Hawk.
I once saw a pigeon hawk flying with some small object in its talons, probably a mouse, which it was apparently eating on the wing. Holding it forward and downward in one foot, it occasionally bent down its head and tore off a bit without slackening its speed. Johan Beetz, of Piastre Bay, Quebec, a close observer of birds, told us that the male feeds the female during the incubation period. He said that this is often accomplished on the wing; the male, having secured a small bird, or mouse, flies toward the nest and calls to his mate, who flies out to meet him; mounting high in the air, 20 yards or so above his mate, he drops his prey; she darts in and seizes it before it reaches the ground, turning over on her back beneath it and seizing it in her talons from below.
Lewis 0. Shelley sends me the following note: “April 30, 1931, late in the afternoon, when two white-throated sparrows were feeding by one of my bird-banding traps, a pigeon hawk alighted in a large cherry tree. It could evidently hear the sparrows while not seeing them. There was a hedge of alders along the brook just beyond my traps; after a few minutes of unavailing watching on the hawk’s part, because the sparrows had detected its presence and ‘froze’, it surprised me by flying headlong into the alders with a great confusion, in an effort to frighten the birds to flight. One ran directly into a trap and ‘froze’, and did not move for ten minutes, even after the hawk had gone; the other moved, as the hawk apparently intended, and a sudden swoop from the hedge, a screamed cry from the whitethroat, and the hawk had its prey. This seemed a daring way of frightening intended prey to take wing.”
Behavior: The flight of the pigeon hawk is swift and dashing, like that of the larger falcons. Its trim body is propelled at tremendous speed by the rapid motion of its long, pointed wings. Few, if any, birds can escape it in straight away flight; even the black swift,one of our fastest-flying birds, has been captured by it. But the prowess of this and other falcons has been somewhat overestimated by admiring observers; it is not always successful, and it often fails to capture birds of much slower flight that are skillful at dodging. William Brewster (1925) tells of a pigeon hawk’s attempt to capture a titlark:
Titlarks were particularly abundant. As I was watching not less than one hundred of them circling over the marshes, a Pigeon Hawk dashed repeatedly into the midst of the crowded flock without capturing any of its members, although one was finally separated from the rest, and pursued for upwards of five hundred yards. The Hawk rose above and stooped down at it fully twenty times in quick succession, with lightning speed and faultless grace. More than once I thought it had it in its talons, but it always eluded them at the critical moment by an abrupt turn or twist. This he could not seem to follow, but invariably descended straight for several yards farther before checking his impetus, to mount and swoop again. All the while the Titlark was nearing, if by devious courses, a dense thicket of alders into which it plunged at length, to be seen no more.
He also witnessed the repeated attempts of a pigeon hawk to capture one of a small flock of blue jays; in spite of his swift and spectacular dashes, the falcon always failed, as the jay always succeeded in dodging or dropping into a treetop, where the falcon did not attempt to attack it; a sharp-shinned hawk would have dashed in after it.
Taverner and Swales (1907) relate the following incident, witnessed by W. E. Saunders: “We had fired at and wounded a Black-bellied Plover which was flying over Lake Erie. The wounded bird was at once pursued by this falcon. Attaining a height of thirty or forty feet above the plover, who was only five or six feet above the water, the falcon swooped and missed: the plover dodging. Again he rose and swooped, and again missed. This was repeated perhaps six times, the birds drawing away northeast towards the mainland, when finally the falcon was successful and struck the plover, knocking him into the water. He then rose,~and with a careful swoop, picked him up and flapped away to the Point and we saw him no more.”
Referring to the flight of this falcon, Ernest Thompson Seton (1890) says: “One trick of flight they had in common with the Whisky John, Shrike and others, namely, flying low over the ground towards a post or stump, and just as one expects to see them strike the bottom of it there is a sudden spreading of tail and wing, and the bird gracefully bounds straight up to the top and alights there. This species will sometimes hover, though they do not make such a practice of it as the Sparrow Hawks.”
Richard M. Bond (1936a) made some interesting observations on the speed in flight of some pigeon hawks that he was training for falconry. He found that a trained bird, in coming to the lure, flew at the rate of 29.9 miles an hour, but estimated that, in pursuit of a flying quarry, it would fly about 50 percent faster. He says, also: “In comparing it with birds it was attempting to capture, it was observed that the Pigeon Hawk flew faster than quail (Lophorty.~ californica) or Meadowlarks (Sturnella neglecta), and more slowly, at least in a rising flight, than Horned Larks (Otocoris alpestris). It could catch a shrike (Lanius ludovicianus gambeli) in a long course free from cover; it was keener after shrikes than after any other bird. It could catch, bring down and kill a dove (Streptopelia risoria), or even a strong adult common pigeon if released within about 50 feet., but was easily outdistanced by these birds after they had attained top speed.”
Pigeon hawks are notoriously bold, fearless, and unsuspicious; they allow a close approach when perched and will fly quite near a man in the open; hence tbey are often shot. About their nesting sites they are far too solicitous for their own welfare. At every one of the three nests that I have seen the birds came flying out to meet us long before we reached the vicinity of the nest, crying in distress, advertising the proximity of the nest, and encouraging us to hunt for it. While I was examining the nests the birds were most solicitous and bold, flying about the tree, perching on nearby trees, sometimes darting past or down at me in swift falcon swoops, and sometimes circling with a slow, hovering flight, their sharp, pointed wings vibrating rapidly; and they were constantly cackling in their harsh, shrill, chattering notes.
W. J. Brown (1912) had similar experiences in Newfoundland, for he writes: “I might here state that the Pigeon Hawk is probably the most curious and inquisitive of the Raptores. The section men on the railway told me that they were always greeted by a pair of Pigeon Hawks when they passed down in the hand car, although the nest was a quarter of a mile off in the woods. * * * One day in June, 1911, we pitched our camp out on the barrens. A pair of Pigeon Hawks, which had their nest on the side of a mountain one mile away, observed the smoke from our fire and immediately came over our heads, uttering alarm notes.”
Its behavior with other species is no less interesting. Dr. E. W. Nelson (1887) in Alaska “saw one of these birds dart down and strike its talons into the back of a Burgomaster Gull (Larus glaucus) as the latter was flying over the sea; after holding on for a moment: the gull continuing its flight unimpeded: the falcon let go, and rising almost directly up for 30 or 40 yards made off.” Harold H. Bailey (1906) saw one chasing a red-billed tropichird on the west coast of Mexico; he also saw it put to flight gulls and caracaras that were feeding on carcasses. William G. Fargo writes to me that on a long, narrow lake in Florida he saw a number of kingfishers strung along at intervals, and practically every one of them was attended by a pigeon hawk, sitting some 10 or 20 yards away; and when the kingfisher moved the hawk went along too. Mr. Brewster (1925) witnessed the following peculiar behavior of a pigeon hawk:
lie was either playing or fighting with a Crow, the former I thought, for although the behavior of both birds was rough and aggressive, it seemed to represent mutual participation in a sportive game curiously regulated and much enjoyed. Thus the successive lungings and chasings were not either one-sided or haphazard, but so conducted that each bird alternately took the part of pursuer and pursued, and when enacting the latter role gave way at once, or after the merest pretense of restance, to flee as if for its life, dodging and twisting; yet it was prompt enough to rejoin the other bird at the end of such a bout, when the two would rest awhile on the same stub, perching only a few feet apart and facing one another, perhaps not without some mutual distrust. During these aerial evolutions the Hawk screamed and the Crow uttered a rolling croak, almost incessantly. They separated and flew off in different directions when my presence was finally discovered.
James S. lime (1919) picked up, in Alaska, “a pigeon hawk that had been in an encounter with magpies. The hawk received such severe treatment that it was unable to fly away and it allowed me to walk up to it. The single magpie which was engaging the hawk when I first realized that a fight was on flew gracefully away on my approach to join six others of its kind which, very likely, had been helping in a common attack upon their enemy.”
Voice: The caching notes heard near the nest reminded me, in form at least, of the protesting notes of the sharp-shinned hawk, though they were louder and harsher. Dr. Townsend (1920), who was with me, recorded the cry as “a rapidly repeated wheet, wheet, whed varied to a hi, hi, hi, harsher in the female than in the male.” Ora W. Knight (1908) records the same notes as “an angry ate, ate, cac, cac, cac varied by a shrill piercing hi-e-e-e-e-e.” Mr. Brewster (1925) heard one “uttering, while still on the wing, a rapidly delivered Ha, Ida, Ida, i’da, Ida, Ha almost precisely like the familiar outcry of the sparrow hawk.”
Field marks: The falcon form and manner of flight are characteristic. It could hardly be confused with the larger falcons, but it might easily be mistaken for a sparrow hawk, unless the colors could be seen plainly; the brilliant colors and the conspicuous markings of the sparrow hawk are very distinctive with any reasonable amount of light; in the pigeon hawk the slaty-blue back of the adult male and the dark brown back of the female and young bird are distinguishable only in a good light, but the black tail, with whitish bands, is more conspicuous.
Fall: It is during the fall migration that most of the pigeon hawks are seen. They come straggling along from September to November, but the height of the migration comes late in September and early in October, together with the heavy flight of small land birds. At that season they are oftenest seen in open country, along the borders of streams or large bodies of water, or along the seacoast. A. L. and H. L. Ferguson (1922), referring to Fishers Island, N. Y., say: “The Pigeon Hawk is very common at the Island during migration. These small falcons prefer a southwest wind to fly on, though numbers come along on a northwest wind. They feed early in the day, and rarely is one collected that is not found to be packed full of birds. They are very savage, and are ready to fight at any time, either with another Pigeon Hawk or a decoy owl. At the decoy we have seen one return seven times, dashing in and squealing, but never striking. They decoy better than the Sharpshins, and when once near the owl are not afraid of a person. The young birds migrate first, and the adults later, like the Sharp-shinned Hawk.”
Lucien M. Turner’s latest date for Fort Chimo, Ungava, where the species is rare, is September 25. Arthur T. Wayne (1910) gives the dates for the migration through South Carolina as ranging from September 13 to November 7. He says: “It is most frequently seen in October, when large flights sometimes occur, as on October 10, 1903, when I witnessed an enormous migration lasting through the whole day. Nearly all of these hawks were flying beyond gun shot and but one specimen was taken. Adult birds are very rarely seen or taken, and a male secured April 13, 1900, and a female taken November 7, 1898, are the only adult birds I have ever seen. Although this species is said to ‘winter in Massachusetts and to the southward’ it certainly does not occur at that season on the coast of South Carolina.”
Ivan R. Tomkins writes to me that he has seen it near Savannah, Ga., “all through November, and once on January 24.” Probably it does not spend the winter regularly much north of Florida, where it is fairly common at that season, arriving during the latter part of September and remaining until April.
Range: T he species is circumpolar, Old World forms breeding from Iceland and the British Isles, across northern Europe and Asia, to Kamchatka and wintering south to northern Africa, India, Turkestan, China, and Japan. The North American races breed from Alaska across Canada to Newfoundland and winter south to the West Indies and northern South America.
Breeding range: In North America the pigeon hawk breeds north to Alaska (Kobuk River, Gens de Large Mountains, and possibly
Demarcation Point); Yukon (La Pierre House); Mackenzie (Peel River, Fort Goodhope, Fort Anderson, Foff Rae, and Hill Island Lake); northern Manitoba (Lake du Brochet and Fort Churchill); northern Ungava (Chimo); and Labrador (Okak). East to Labrador (Okak and Groswater Bay); eastern Quebec (Romaine); Newfoundland (Deer Lake and St. Johns); Prince Edward Ish~nd (North River); and Nova Scotia (Halifax). South to Nova Scotia (Halifax); southern New Brunswick (St. Stephen); Maine (Dover); southern Quebec (Quebec) ; southern Ontario (Charlinch and Lake Joseph); probably Ohio (Ashtabula County); rarely Iowa (Grinnell, probably Iowa City, and probably Sioux City); Colorado (Summit County and Fort Lewis); southwestern Wyoming (Fort Bridger); northern Utah (Wasatch Mountains); northern Nevada (Buffalo Creek); and southern Oregon (Lake Malheur and Klamath Lake). West to Oregon (Kiamath Lake, Fort Klamath, and Newport); Washington (Bumping Lake, Tacoma, and Wrights Peak); British Columbia (Chilliwack, Okanagan, and Glenora); and Alaska (Chitina River, Seldovia, Nogheling River, Mount McKinley, Jennie Creek, and Kobuk River).
Winter range: In the East most of the pigeon hawks retire in winter south to the Gulf States, the Caribbean region, and northern South America. Nevertheless, frequency of records in December and January actually extends the range much farther north.
At this season the species has been recorded north to southern British Columbia (Okanagan); southeastern Washington (Walla Walla); Utah (St. George); northwestern Wyoming (Yellowstone Park); Colorado (Plateau Creek and Boulder); Nebraska (Crawford and Neligh); rarely Iowa (Sioux City, Ashton, and Keokuk); Illinois (De Kalb, Urbana, and Rantoul); probably rarely Indiana (Bicknell and Richmond); rarely southern Ontario (Toronk and Ottawa); rarely southern Quebec (Montreal); and rarely southern Maine (Portland). East to rarely southern Maine (Portland); rarely Connecticut (New Haven); rarely Maryland (Westwood); rarely South Carolina (Charleston); Florida (Gainesville, New Smyrna, Miakka, and Fort Myers); Bahama Islands (New Providence); Dominican Republic (Monte Cristi, Moca, Miranda, and La Vega); Puerto Rico (Mayaguez and Cartagena Lagoon); and the Lesser Antilles (Anguilla, Antigua, probably St. Vincent, probably Barbados, and Trinidad). South to the Lesser Antilles (Trinidad); northern Venezuela (Altagracia and Caicara); and rarely Peru (Trujillo). West to rarely Peru (Trujillo); Ecuador (Cuenca, Canar, Zambiza, and Esmeraldas); Colombia (Medellin); Panama (Calobre); Costa Rica (San Jose); Oaxaca (Tehuantepec); Puebla (Chietla); Sinaloa (Mazatlan); Baja California (La Paz); California (San Diego, Buena Park, Santa Barbara, San Jose, Marysville, and Willows); Oregon (Portland); Washington (Quilcene, Seattle, and Smith Island); and British Columbia (Okanagan).
The range above outlined combines the four races currently recogniz~ed as North American. The eastern pigeon hawk (Falco columbarius columbariu.s) breeds in the eastern part of the range west to the eastern border of the Great Plains and winters south through the West Indies and eastern Mexico to northwestern South America. The black pigeon hawk (F. c. suckle yi) is found during the nesting season only on the coastal islands of southern Alaska and British Columbia, wintering south rarely as far as San Francisco Bay. Richardson’s pigeon hawk (F. c. richardsoni) occupies the Great Plains region from southern Alberta and Saskatchewan south in winter through Colorado and New Mexico to Texas and probably northwestern Mexico. The western pigeon hawk (F. c. bendirei) breeds from northern Alaska, Yukon, and western Mackenzie south to Saskatchewan, Alberta, and British Columbia and through the mountains to northern California, wintering south through C’alifornia to New Mexico, northern Mexico, and Baja California.
Spring migration: Early dates of arrival north of the winter range are: New Brunswick: Scotch Lake, April 2; St. John, April 7. Nova Scotia: Pictou, March 26. Prince Edward Island: North River, April 16. Newfoundland: Placentia Bay, February 13. Wisconsin-Milwaukee, March 10; Elkhorn, March 15; Whitewater, March 17. Minnesota: Cottonwood County, March 20; Heron Lake, March 27; Wilder, April 2; White Earth, April 12. South Dakota: Vermillion, March 11; Brookings, March 22; Yankton, March 25. North Dakota: Argusyille, March 25; Larimore, April 6; Bathgate, April 9. Manitoba: Margaret, March 31; Killarney, April 1; Treesbank, April 7; Aweme, April 9. Saskatchewan: Eastend, March 15; South Qu’ Appelle, March 18; Skull Creek, March 22; Muscow, March 25. Mackenzie: Fort Simpson, April 25; Fort Providence, April 27. Idaho: Cocur d’Alene, April 16. Montana: Terry, March 7; Fortine, April 16 (one seen January 15, 1931). Alherta: Alliance, April 11; Nanton, April 13; Stony Plain, April 15; Fort McMurray, April 21. Alaska: mouth of Stikine River, April 19; Kuiu Island, April 25; Strelna, May 8; Husbagab, May 10; Fort Yukon, May 13; St. Michael, May 18; Kowak River, May 19.
The last individuals appear to leave the southern parts of the winter range in March and April. Some late dates of departure from this region are: Virgin Islands: St. Croix, April 28. Puerto Rico: Lajas, April 1. Dominican Republic: Lake Enriquillo, March 5. Florida-Key West, April 3; Pensacola, April 22; Dunedin, April 30. Louisiana: Chenier Tigre, March 10.
Fall migration: Late dates of fall departure from the northern parts of the breeding range are: Alaska: Unalaska, September 25; Taku River, September 26; Admiralty Island, September 30. Yukon: mouth of Moose River, October 1. Alberta: Calgary, October 14; Fort McKay, October 15; Belvedere, October 18. Montana: Big Sandy, September 30; Fallon, October 22. Mackenzie: Fort Resolution, September 27; Grand Detour, Slave River, October 3; Roche Trempe-l’eau, October 8. Keewatin: Oxford House, September 10. Saskatchewan: Eastend, October 4. Manitoba: Oak Lake, October 19; Ninette, October 28; Killarney, November 4; Aweme, November 15. North Dakota: Argusville, October 14; Grafton, October 18. South Dakota: Yankton, October 16; Forestburg, October 24; mouth of the Vermillion River, October 25. Minnesota: Minneapolis, October 6; St. Vincent, October 11; Virginia, October 16. Wisconsin: Shiocton, October 9; New London, October 14; North Freedom, October 30. Prince Edward Island: North River, October 3. Nova Scotia: Pictou, October 17; Halifax, November 4. New Brunswick: Scotch Lake, November 3; St. John, November 5.
Early fall arrivals in the southern part of the winter range are generally in September and October. Among such are: Florida: Pensacola, September 4; St. Johns County, September 15; Wakulla County, September 27. Puerto Rico: Mayaguez, October 1. Venczuela: Culata, September 18.
The banding files of the Biological Survey contain two records that throw light on the movements of this species. Both birds were banded at Rosebud, Alberta, and are for the subspecies richardsoni. One banded on July 8, 1930, was shot in the Gila Valley, near Stafford, Ariz., on December 12, 1930, while the other, banded on July 6,1931, was recaptured near Tucson, Ariz., on January 28, 1933.
Casual records: The pigeon hawk is probably a fairly regular fall and winter visitor on Bermuda, but only two records are now available. One was seen on December 2, 1874, and the following day a specimen was obtained. Another was taken on March 23, 1919.
Egg dates: Arctic America: 8 records, May 25 to June 29. Alberta to Manitoba: 19 records, May 7 to June 6; 10 records, May 18 to June 4, indicating the height of the season.
Ontario to Newfoundland: 14 records, May 18 to June 22; 7 records, Ma.y 24 to June 9. Labrador: 8 records, May 15 to June 30.
BLACK PIGEON HAWK
FALCO COLUMBARIUS SUCKLEYI Ridgway
This dark race of the pigeon hawk is supposed to be resident in the humid, northwest-coast region, but the limits of its restricted range are none too well known. It is supposed to breed in British Columbia and to wander only rarely as far south as northern California. Major Bendire (1892) writes:
I am quite positive, however, that an occasional pair breeds in the vicinity of Fort Klamath. On May 9, 1883, while en route from this post to Linkville, Oregon, I observed a pair of these birds in the large open pine forest about midway between the two points. I had halted my party to let the horses graze, and, while resting, my attention was attracted to the male, by its incessant screaming in the trees overhead; this also brought the female around, and she was equally as noisy. It was clear that they had a nest in the vicinity, either in the tall pines or in a cliff about 400 yards distant, but a careful search instituted by the members of my party and myself failed to reveal it. Both birds were rather shy, but I finally succeeded in killing the male, a very handsome adult specimen.
J. H. Bowles (Dawson and Bowles, 1909) says: “Black Merlins are fairly common throat the country lying between the Cascade Range and the Pacific Ocean [in Washington]. They are most numerous during migrations, but a few pairs remain with us during the summer for the sake of raising a family.
“During the fall and early spring they are most often to be met with in the open prairie country, and on the extensive tide flats that are to be found along Puget Sound. In such localities there is always an abundance of the smaller migratory birds, which seem to make up almost the entire sum and substance of their food supply.”
S. F. Rathbun has very kindly looked over for me the pigeon hawks in local collections and reports that all the specimens of suckleyi, taken in the vicinity of Seattle and Tacoma, Wash., were migrant or winter birds, September to March. From this he infers that “quite likely, in this locality, the bird is much more of a transient than a resident, although our notes, some thirty years ago, show that for several seasons we saw the species at times about the city in the summer months.”
Dr. George M. Sutton writes to me that he shot an exceedingly handsome, richly colored male of this race, on June 16, 1934, about three miles north of Blue River, British Columbia. The stomach contained “only the remains of a Vaux’s swift.” The gonads were considerably enlarged. He says: “Judging from this record, and from a similar one made by Taverner in an earlier year, I am inclined to think this bird may nest far in the interior, as well as, or perhaps instead of, along the coast, as has been supposed.”
Nesting: Mr. Bowles (Dawson and Bowles, 1909) writes:
So far as known no positively identified eggs of the Black Merlin have ever been taken, and only two nests have been reported to me, both of which were in inaccessible cavities high up in decayed trees. One of these that I personally visited in June was placed in a lone cottonwood tree in the valley of the Puyallup River, and contained young that were learning to fly. The young paid no attention whatever to me, but the parents sat overhead looking down at me and uttering plaintive whimperings, although seemingly pretty well assured that I could not reach them. The note sounded not unlike the kik-kik-kik call of the Flicker, only very much more subdued, and is the only sound I have ever known this bird to make at any time.
There is a set of four eggs in the A. M. Ingersoll collection, taken by L. D. Rice near Sitka, Alaska, on May 27, 1887, from a “nest of sticks, lined with leaves and feathers, built on top of a rock about eight feet high.” These eggs are now stored in the museum of the San Diego Society of Natural History.
Plumages: The molts and plumages evidently follow the same sequence in the black pigeon hawk as in others of the species, but suckleyi is much darker than columbarius in all plumages. In the juvenal plumages of both sexes and in the adult female, the upper parts are “fuscous-black” to “clove brown” in fall birds, somewhat paler in spring; the tail bands are narrow and broken, or restricted to mere spots; the under parts are heavily marked with broad streaks of “clove brown” or “bone brown”, the dark colors predominating.
In the adult male the upper parts are “dark plumbeous”, lightest on the rump and tail coverts, deepening to “blackish plumbeous” on the upper back and to nearly black on the nape; the tail is black, with white tip spots and three or four interrupted bars or spots of “dark plumbeous”; the chin and throat are white, with narrow black streaks; the remaining under parts are strongly washed with “cinnamon-buff” and broadly streaked with black; the black predominates on the belly and flanks. Mrs. Fannie H. Eckstorm (1902) has given us a fine description, in more detail, of a very dark specimen, an extreme melano.
Behavior: The food, manner of hunting, and other habits of the black pigeon hawk are similar to those of its eastern relative. It is the same bold dashing little falcon. Mr. Rathbun writes to me: “A friend of ours was hunting jacksnipe on marshy pastureland quite some distance north of here. The section was open, although a long distance away was a standing tree or two. The snipe came darting past my friend just within long gunshot. Tie swung on one, and when the gun cracked the bird started falling in a diving, fluttering flight, appearing to have a broken wing. But only part of its descent had taken place when ‘from nowhere’ flashed a small, dark hawk, its flight so swift that it appeared only as a ‘blurr in the air’. The hawk struck the snipe squarely in mid-air, then quickly carried it away. The whole occurrence took place so quickly that, although a shot was fired in turn at the departing hawk, it had no effect, as it was practically out of range when the shot was fired, for my informant was taken completely by surprise at what had occurred.”
Since the above was written, I have been interested in reading the following suggestion by Harry S. Swarth (1935) as to the validity of this dark form as a geographical race:
‘Suckleyi was described, and has been regarded, as an extremely satisfying example of the darkening effect of the humid coastal environment of the northwest, as another ‘saturated’ local race. However, breeding birds are unknown from any point whatsoever, and, so far as I am aware, no specimens of suckleyi have been collected on the coast north of Vancouver Island. On the other hand, migrants have been collected east of the Coast Range the entire length of British Columbia. South-bound migrants collected by myself near Atlin, where the form is not uncommon, were taken such a short distance south of the Yukon Territory boundary as to make it obvious that suckleyi must breed in at least the upper portion of the Yukon drainage. In the Atlin region, columbarius and suckleyi occur in about equal numbers. Indeed, so far as I know, wherever suckleyi has been collected typical columbarius has been found as well. Do not these facts point toward the probability of the existence of two color phases of Falco columberius in the northwest rather than of two geographic races? Is there, indeed, anything corroborative of geographic segregation of these forms?”
Hamilton M. Laing (1935) evidently does not agree with the above theory, and produces some evidence to indicate that the black pigeon hawk is a good race and occupies a fairly definite breeding range in the heavily forested coastal region of British Columbia and the interior of Vancouver Island.
RICHARDSON’S PIGEON HAWK
FALCO COLUMBARIUS RICHARDSONI Ridgway
This beautiful little falcon, the palest of the American merlins, is a bird of the Great Plains, breeding mainly in southern Alberta and Saskatchewan, in Montana, and in northwestern North Dakota. Its summer home is on the wide rolling plains and prairies, where they are dotted with small groves of poplars, aspens, cottonwoods, and other deciduous trees. Prof. William Rowan writes to me that in Alberta this falcon “breeds quite regularly, though not abundantly, in the Edmonton district, in the Cooking Lake and the Sullivan Lake districts, also on the Red Deer.” He also thinks that it “breeds farther north than is indicated in the Check-List, at least up to Alaska and possibly to the northern limit of the Canadian Zone.”
This falcon, when first discovered by Richardson, on the plains of the Saskatchewan, was supposed to be identical with the European merlin, which it somewhat resembles. Richardson’s specimen, figured in Fauna Boreali-Americana, plate 25, under the name Falco aesalon was taken near Carlton House on May 14,1827. Its distinctness from that species was not discovered for many years, when Ridgway (1870) described it as a full species and named it for its discoverer. Mr. Ridgway (Baird, Brewer, and Ridgway, 1905) later decided to regard it as a subspecies of columbarius, and it has so stood in the last two editions of our Check-List.
Spring: T. E. Randall writes to me that Richardson’s merlin, as the bird was called for many years, is the first migrant to appear in the spring in the vicinity of Castor, Alberta. His earliest record is February 22, 1924, a male bird. “The bird is quite common by April 1, and the birds have paired and chosen nesting sites by the middle of that month.”
Nesting: Mr. Randall says (MS.) of its nesting habits: “An old crow’s nest is invariably used, generally one that is built in the fork of a poplar, 15 to 18 feet from the ground. The nest is always relined with dry inner bark of poplar. Laying commences about the first of May, and four is the usual clutch, but I have twice found five eggs. If the first clutch is taken, the birds will often take possession of another nest, at no great distance from the first, and lay a second clutch of eggs, but I find that the second clutches number only three eggs. If the nest tree is climbed before an egg is laid, the birds always desert the nest; on one occasion of which I have record the birds returned to their first choice on being disturbed at the second nest. This year, 1924, for the first time in my experience, a pair of merlins nested in a nest that was used by merlins in 1923; after the eggs were taken, a pair of Swainson hawks took possession of the nest and reared their young.”
W. J. Brown spent the spring and summer of 1904 at Lethbridge, Alberta, and has sent me his notes on eight nests of this falcon that he found from May 7 to June 5. Five of these were in old magpies’ nests, one in an old nest of ferruginous roughleg, and two in old crows’ nests. “Two pairs of these birds were nesting in holes in cutbanks, but their nests could not be reached.”
J. E. Houseman (1894) found a nest of Richardson’s pigeon hawk near Calgary, Alberta, in a cavity in the top of a black poplar, where the trunk had been broken off. On May 5 it held only one egg, and a week later there were four perfectly fresh eggs, indicating that an egg is laid every other day. “The cavity these eggs were in was about eight inches across, one and one half feet deep, and 22 feet from the ground.” G. F. Dippie (1895) found two more nests, the following year, in the same general region, in hollows in large black poplars.
Frank L. Farloy sends me the following notes: “I have found five or six nests of this little hawk, and all have been within a half mile of a lake or river, sometimes within a few hundred feet. Two of these were in spruce trees, in dense spruce woods along the Saskatchewan River, from 30 to 60 feet from the ground. Two others were in poplars in small groves on the prairie, averaging 25 feet from the ground. Another was in an old covered magpie’s nest, 15 feet up in a willow clump. All the nests were loosely constructed and looked as if they had been used previously. All the nests were lightly lined with pieces of the inner lining of poplar bark. Both old birds are very noisy, when one approaches the nest, uttering a shrill, scolding note; this action on the part of the birds often leads to the discovery of the nesting tree.”
Eggs: Richardson’s pigeon hawk lays from three to six eggs, usually four or five. Mr. Randall’s notes indicate that four is the usual number, and Mr. Rowan evidently agrees with him; but Mr. Brown took seven sets of five, one of six, and none of four. Most of the eggs are indistinguishable from eggs of the eastern pigeon hawk, but some are more lightly spotted, showing more ground color. Mr. Rowan thinks that they are more like eggs of the hobby falcon (Falco subbuteo) than like those of the merlin. The measurements of 48 eggs average 39.8 by 31.2 millimeters; the eggs showing the four extremes measure 43.3 by 32, 42.7 by 32.5, 37 by 30.5, and 39.1 by 30 millimeters.
Plumages: The sequence of molts and plumages is apparently the same as other pigeon hawks, but this race is easily distinguishable in any plumage by its much paler coloration. The sexes are alike in the immature plumage of the first year. This is similar to the corresponding plumage of columbarius but much paler; the upper parts are “hair brown” to “light drab”, with “cinnamon” edgings when fresh; the under parts are paler and less heavily streaked than in eastern birds.
In the adult male the upper parts are pale, bluish gray, or “cinereous”, slightly darker on the upper back and crown, with narrow, black shaft-streaks; the tail is “gull gray”, or paler, tipped with white, with a broad subterminal band and three interrupted bars of black, the gray bands as wide as, or wider than, the black; the under parts are white, or creamy white, deepening to “cinnamon-buff” on the tibiae and paling to pure white on the chin and throat; the throat and tibiae are lightly, or not at all, streaked with black; the body below is streaked with “buffy brown” or “snuff brown”, with darker shaft-streaks; the white bars on the remiges are wider than the dark spaces.
The adult female is similar to the male but has a distinct brownish cast on the upper parts, much like the immature birds; and there are usually spots of “light oehraceous-salmon” on the outer webs of the wing quills.
Females and immatures are much like the corresponding plumages of bendirei, but paler.
Behavior: We found this little falcon to be quite rare in southwestern Saskatchewan. During two seasons there I succeeded in collecting only one specimen and found no nest; my companions collected another, and we saw two or three other birds supposed to be this falcon. My bird was shy and was secured only by exercising a little strategy. As we were driving along a prairie road we saw a small hawk sitting on a fence post by the roadside; as we approached he kept flying along ahead of us, alighting on the fence posts at frequent intervals, but never allowing us to come within gunshot range.
So I stopped the wagon, alighted from it, made a long detour to a point far ahead of the hawk, and hid behind a bank. As my companion came along, the hawk behaved as he had before and finally flew past me near enough for me to secure him.
I cannot find anything to indicate that the food, voice, or other habits of this bird differ materially from those of other pigeon hawks.
Fall: Richardson ‘s pigeon hawk migrates southward in fall, mainly east of the Rocky Mountains, through Colorado, New Mexico, and western Texas. Mr. Randall says that it is one of the last of the migrants to leave Alberta; his latest record is December 5,1922.
WESTERN PIGEON HAWK
FALCO COLUMBARIUS BENDIREI Swann
This supposed northwestern race of the pigeon hawk is not a very well marked subspecies. It seems to me to be only an intermediate between two of the other races and therefore hardly worthy of recognition in nomenclature. It is said to be slightly paler above than columbarius, which may be due to interbreeding with richardsoni. I am inclined to agree with Harry S. Swarth (1935), who says: “I have examined series of Pigeon Hawks wherever opportunity has offered without being able to substantiate the existence of a western race, bendirci. * * * I am unable to distinguish between eastern and western examples of Falco columbarius in normal plumage, but it may be desirable to recognize a northwestern subspecies on the same grounds as Buteo borealis calurus, that is, on the basis of a dimorphism that is prevalent over part of the species’ range. For this subspecies the name Falco columbarius suckleyi is available, of course; bendirei should be ruled out in any event.”
What little we have available on the habits of pigeon hawks, in the regions supposed to be occupied by this race, indicates no variation from the habits of the species elsewhere. M. P. Skinner tells me that he has seen them in Yellowstone National Park, some of them “quite dark”, during every month from April to October; his earliest date is April 15, and his latest October 10. He says that “these hawks are like the sharpshins in preferring the edges of the forests and the open country, dotted with groves, to the heavy forests.”
Nesting: H. R. Taylor (1888) writes of a nest, containing five eggs, that he found on April 6,1888: “It was on a steep mountain side, in Santa Clara Co., Cal., on a ledge of a precipitous bluff about thirty-five feet high.” The nest “was composed simply of pieces of friable rock.”
Behavior: Mr. Skinner says, in his notes: “Although most of the pigeon hawks’ prey are small birds flushed and chased down, they are versatile hunters. I have seen them circle over and hunt a meadow as a red-tailed hawk would; and I have seen one hover in air for some time like a sparrow hawk and then shoot straight down to the ground at high speed.”