Part 26

Casual records.--The records for Greenland and eastern America have been mentioned. In Iceland Faber recorded the first on September 6, 1819, and since then other occurrences have taken place without exact date. To the Faroes it is only a straggler in the winter months. In the Canaries it is an occasional visitor, chiefly to the eastern isles, and has been seen there as late as June 14. It has also been recorded from the Azores, Madeira (December 7, 1893, October 25, 1896, October 28, 1896, January 30, 1897, and great numbers on April 28, 1898) and the Cape Verde Islands.

Egg dates.--British Isles, April 17 to May 31 (42 dates), April 20 to May 10 (26 dates). Holland and Germany, earliest date April 6. Scandinavia from about mid May onward, May 13 to 26 (6 dates).

NUMENIUS HUDSONICUS Latham

HUDSONIAN CURLEW

HABITS

A striking case of the survival of the fittest is seen when we compare the relative abundance of the three common species of North American curlews to-day with their status 50 years ago. Whereas, at that time the Hudsonian curlew was the rarest of the three, it is now by far the commonest. The vast flocks of Eskimo curlew, that formerly frequented the Labrador coast every summer and visited the New England coast at frequent intervals, have all disappeared. They were tame and unsuspicious, were easily decoyed, and were therefore slaughtered in enormous numbers on their feeding grounds; they made a long migratory flight over the ocean from Nova Scotia to South America, where many undoubtedly perished in stormy weather. The long-billed curlew, once so common all over the interior prairie regions, and even on the Atlantic coast, has gradually been driven westward and northward, until it is now occupying a comparatively restricted range. The long-billed will probably be the next of the curlews to disappear, perhaps within the near future. But the Hudsonian curlew, on the other hand, has held its own, and in some sections it has apparently increased. This increase, however, is probably more apparent than real, due to comparison with other species which are decreasing rapidly. The reasons for its success in the struggle for existence are not hard to find. Its breeding grounds are in the far north, where it is never disturbed; it has no dangerous migration route; it does not ordinarily migrate in large flocks, which are susceptible to vicissitudes of weather and great slaughter at the hands of gunners; but, above all, it is a shy, wary, wily bird, quite capable of taking care of itself and well fitted to survive. Like the crow, it is more than a match for its enemies.

The Hudsonian curlew was evidently comparatively rare in Audubon’s time, for he apparently knew very little about it. Wilson seems to have overlooked it entirely or to have confused it with the Eskimo curlew, and Nuttall’s remarks are not altogether clear on the subject. George H. Mackay (1892b) says:

Speaking for Nantucket and Tuckernuck Islands, as far as I am aware, not over 15 or 20 of these birds a year on an average have been shot there during the past 17 years, and the local saying, that “it does not pay to go after them,” is true, they being too shy and too limited in number to make it any object, either for gain or for pleasure. During these 17 years there have never been more than 100 birds on an average living on the above islands each year, and for the past few years I have noticed a falling off from this number.

I am quite sure that I have seen more Hudsonian curlews on Cape Cod during the past 10 years that I saw during the previous 20. The species certainly has not decreased, and I am inclined to think that it has increased. The 1927 fall flight was unusually heavy.

Spring.--From its winter range on the Pacific coast of South America this curlew migrates through Central America to Florida and up the Atlantic coast. It reaches Florida during the latter half of March, the Carolinas about the middle of April, and Massachusetts about the middle of May. During a week spent with Arthur T. Wayne on the South Carolina coast May 18 to 25, 1915, I saw the last part of a heavy flight of Hudsonian curlews. Mr. Wayne told me that the first birds come early in April, but the height of the migration is between the third week in April and the second week in May, when enormous numbers (he says hundreds of thousands) may be seen every day. We saw no such numbers, but numerous flocks were seen every morning flying in to feed on fiddler crabs on the extensive marshes and flying out again at night to roost on the sand bars and islands. They flew high in the air in V-shaped flocks or in long irregular lines and their loud notes could be heard almost constantly.

Herbert K. Job (1905) saw them here in “scores of thousands”; he spent a night at each of several little low islands--mere sand bars--lying off the coast, and says:

About half past 5 or 6 o’clock, when the sun was low in the horizon or had set behind a cloud bank, the first advancing line is seen, and a string of from a dozen to 50 Hudsonian curlews come scaling over the beach, to alight on the bar, down at the other end. After a few minutes another flock is seen approaching. By half past 6 they are arriving fast, and by 7 there are two or three flocks in sight all the time, some of them containing as many as 75 birds. Meantime I am shooting at them as they pass, with my reflex camera, despite the dull light. As may be imagined, the company on the sand has become immense, covering many acres. They keep up a sort of murmuring noise, and now and then all fly up, with a perfect storm and tumult of wings and voices, soon to alight again. Even after dark they are yet arriving, as one may hear. I hazard the guess that there are often 10,000 curlews at such a roost each night. At the first glimmer of day they are off again for the marshes.

Mr. Wayne (1910) makes the following interesting suggestion:

This species supplanted the long-billed curlew between the years 1883 and 1885, for previous to these dates the former species was rare, but it gradually became more abundant each year until it established itself firmly in great numbers. The result was that the long-billed curlew was driven from its accustomed range by a smaller species in the struggle for existence. The long-billed curlews fed almost entirely upon fiddlers, and the Hudsonian curlew also subsisted upon them, and as the food supply was inadequate, one species was forced to seek other paths of migration.

The Hudsonian curlew seems to be a rare migrant everywhere in the interior; some of my correspondents do not mention it at all and others give only scattering records. But William I. Lyon writes to me that he saw a flock of about 100 on May 22, 1926, in Illinois; they were flying in V formation, uttering their characteristic four short whistles, and breaking sometimes from a V into a line. Edwin Beaupre tells me that “the foot of Amherst Island, in Lake Ontario, is a favorite crossing place for these curlews in their northward flight. May 24 is the date on which they may be looked for, passing through this locality in one large flock.”

J. A. Munro (1911) records a heavy flight which occurred at Fisherman’s Island, Toronto, during three days, May 24 to 26, 1910; a careful count was made of passing flocks in which over 1,000 birds were recorded. Probably the main flight from the Atlantic coast turns inland before it reaches New England and flies by way of the Great Lakes to the west side of Hudson Bay. The species is rare in New England in the spring.

Along the Pacific coast there is a heavy migration; the main flight appears in southern California about the middle of March, progresses slowly northward, reaches Alaska about the middle of May, and arrives on the breeding grounds in northern Mackenzie by the end of May. In California the main migration route is coastwise, the bulk of the flight coming in April; but John G. Tyler (1913) records them as “regular spring migrants” in the interior valleys. “Their favorite resorts are large, open fields where shallow ponds occur, and in such places they often gather in large numbers.” D. E. Brown’s notes record them as common, or very abundant at times, in Washington, flocks of 40 or 50 birds being not at all uncommon; his dates run from April 7 to May 14.

Nesting.--The best account of the nesting habits of this species and its behavior on its breeding grounds is given us by Dr. Joseph Grinnell (1900), who found eight nests in the Kotzebue Sound region of northern Alaska; he writes:

I found the Hudsonian curlew to be a common breeding bird over the tundras from Cape Blossom eastward into the Kowak Valley. In the vicinity of our winter camp on the Kowak, the arrival of the curlews was on May 17. From the middle to the last of June, in the Kowak delta, I became well acquainted with the Hudsonian curlew. At this season they were of course mated and most of them had eggs. They were ordinarily met with on the open stretches of tundra, often where these alternate with strips of timber and lakes. Where such perches are afforded, solitary birds on watch would be seen sitting on the tips of isolated dwarfed spruces or even willow bushes. As soon as an intruder entered the domains of a pair of curlew, the bird on watch would give the alarm by a loud, ringing call note, and soon both birds would fly to meet him. As long as the intruder remains in the vicinity, the pair of birds keep flying restlessly to and fro, now and then alighting on the ground and walking about, but most of the time keeping up their monotonous rolling whistle. This was the only note I heard, except earlier in the season a long, faint whistle like that of a distant locomotive, uttered by the male bird while sailing slowly, on set motionless wings over the nesting grounds. This is probably their song flight, though it is certainly very simple. The far-off whistle, however, puzzled me for some time as to its origin. I at first thought it was a steam launch on the river somewhere, until I finally connected the sound with the slow soaring of the curlew overhead.

The eggs so closely resemble the monotonous lights and shadows of the surrounding moss and grass that I have stepped directly over the nest, all the while scrutinizing every foot of the ground about me, without detecting the eggs. Sometimes from the nature of the surroundings the eggs are more conspicuous and can be seen 10 yards or more, but this is the exception. While one is at the nest, the parents fly close about one, almost deafening one with their loud penetrating cries. If anything the male bird is the most demonstrative of the two. The nest is simply a saucer-shaped depression in the top of a low hummock of moss or grass. The locality was always a wet swale or low place in the tundra, in which the clumps of grass or moss were often surrounded at their bases with water. The nests were in no way protected, the eggs always being in plain view, but the remarkable mimicry in their coloration is generally of sufficient protection.

MacFarlane collected some 13 sets of eggs on the barren grounds west of the lower Anderson River, but I find only one nest described in his notes; this he said was “a depression in the ground, lined with a few decayed leaves.” Stanton Warburton, Jr. took a set of three eggs near Teller, Alaska, on July 4, 1924; he writes to me that “the nest was situated on hard, dry tundra, the eggs occupying a slight depression in light grasses; distinctive nesting material of grey lichen-light material covered the cavity. Both birds were present.” A nest found by Bishop J. O. Stringer on an island in the lower Mackenzie River is described as a pile of grass, moss, and weeds.

Eggs.--The Hudsonian curlew lays almost invariably four eggs, though the set of three referred to above was heavily incubated. The eggs are hardly, if at all, distinguishable from those of the European whimbrel. They are ovate pyriform, rather pointed, in shape and show little or no gloss. Doctor Grinnell (1900) describes them as follows:

Their ground color is very variable, from a bluish pea green through olive buff to light olive green. The markings are numerous and somewhat amassed at the larger ends of the eggs. They consist of dots, spots, and blotches of pale lavender, drab, Prout’s brown, and bistre. The latter seems in every case the real pigment, and the varying depth to which it is covered with subsequent layers of shell material, seems to account for the different tints, even to the palest lavender.

In the few sets that I have seen the prevailing ground colors are dark and light shades of “olive buff,” with occasionally “Isabella color” or “ecru olive.” In the markings I recognized various browns, such as “bone brown,” “warm sepia,” “Saccardo’s umber,” “olive brown,” and “buffy brown.” The measurements of 37 eggs average 57.5 by 40.7 millimeters; the eggs showing the four extremes measure =61.9= by 41.7, 59.2 by =43.2=, =52= by 38.5, and 55 by =37.2= millimeters.

Plumages.--I have never seen a downy young Hudsonian curlew, and, so far as I know, it has never been described. Young birds are in juvenal plumage when they reach us on migration. They are more easily recognized by their much shorter bills than by any plumage differences, as they look much like adults. The markings on the neck and breast are finer and closer; the feathers of the back, scapulars, tertials, and wing coverts are “warm sepia,” notched with cream-white or pale buff, producing a spotted effect, most pronounced on the wing coverts and tertials (in adults these parts are more narrowly edged with buff); the rump is “sepia,” with large spots of “pinkish buff,” and the upper tail coverts are barred with the same colors; the under parts are more buffy than in adults and the whole effect is brighter and more variegated.

A postjuvenal body molt in late fall or early winter, which almost runs into a first prenuptial molt, produces a plumage, which can be distinguished from the adult only by the faded juvenal wing coverts and the bird becomes fully adult at the next postnuptial molt.

Adults have a complete postnuptial molt, beginning with the body molt in August and ending with the molt of the primaries in the winter; soon after the wings are molted, or from February to May they have a partial prenuptial molt, including the body plumage, the tail, and some of the scapulars and wing coverts.

Food.--Hudsonian curlews are mainly shore feeders; on the beaches and sand flats they pick up various insects, worms, small mollusks, and crustaceans, often probing for the sand fleas in the wet sand; on the mud flats they find similar animal food. I have also often seen them on the marshes, or even on high, dry pasture lands, such as are frequented by golden plover and Eskimo curlews, where they find grasshoppers, spiders, beetles, and other insects. In South Carolina we saw them at low tide on the oyster banks and on the mud banks riddled with holes of fiddler crabs, on which they were doubtless feeding. In the Magdalen Islands I have seen them on the uplands and among the sand dunes, where they were evidently eating crow berries (Empetrum nigrum). They are also said to eat blueberries, dewberries, and various seeds. E. W. Hadeler tells me that he once saw them feeding on the bodies of light-colored millers; the beach was lined with these moths, some dead and others alive, and the curlews did not like to leave this abundant supply of food.