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Eskimo Curlew

A vanishing species?

Life History -- Briefly Stated

Breeding Biology | Migration | Habitat | Food and Feeding Habits | Other Behaviour | Voice | Hunting | Decline

This is a summary of the curlew's annual cycle in the 1800s through breeding, fall migration, wintering and spring migration. These aspects are expanded upon and documented in the geographical treatment and appendices (Map 3 & Map 4 ). The only references given in this chapter are those not appearing later.

Breeding Biology: Eskimo Curlew nests have been found only in the Northwest Territories, although the species almost certainly bred in Alaska and possibly in eastern Siberia and on some of the Canadian Arctic Islands. In the vicinity of the Anderson River, NWT, MacFarlane collected information on 38 nestings of the Eskimo Curlew of which parts of at least 28 sets of eggs apparently reached the Smithsonian (Appendix 1). Although this species received only an insignificant fraction of his attention-39 of 5000 items, yet a considerable amount of breeding biology may be gleaned from MacFarlane's meticulous notes.

MacFarlane defined breeding habitat quite clearly: "Not seen before entering the Barrens" (23 June 1862) and "This Curlew never, in this quarter at least, breeds in wooded tracts-the Barren Grounds proper being the real habitat of the species during the season of nidification" (23 June 1864).

Twenty-two of his nestings had four eggs (or four young) and three had three at the time of inspection. There were six two-egg clutches and two with one, but there is no way of knowing whether these were the result of incomplete laying, partial loss to predators or partial hatching. Four was the complement of eggs in at least two-thirds of the clutches. (Five records were not precise enough to use in these calculations.)

The ground colour of the eggs was "olive-drab, tending either to green, gray or brown....The markings, always large, numerous and bold," were dark brown (Coues 1874:512; Fig. 14). Average measurements of 36 eggs were 51.3 by 35.5 mm (Bent 1962:128-129).

MacFarlane gave descriptions of 19 nests in the notes we have. Variations on the following-the most detailed one-are still so similar as to become monotonous: "Nest a mere hole in the earth, lined with a few decayed leaves, and having a thin sprinkling of hay in the midst of them" (#282).

MacFarlane apparently assumed that the incubating bird was a female. He referred to it in this manner whether the skin was delivered by an Eskimo or whether he himself witnessed the collecting. There is no indication that he prepared any of the skins and, therefore, might have sexed the birds internally; there is no mention of the condition of ovaries or gonads which, no doubt, he would have recorded. For #3170 he lists 2 skins as male and female but says that both may be females. He twice lists the male collected but not the female of a pair, probably because it was the second bird to appear (#3534, 3535). Unless MacFarlane's assumption is correct, there is doubt about the sex of specimens in museums. Both parents incubate in the Little Curlew of Siberia and in the Whimbrel at Churchill, Manitoba (Labutin et al. 1982:309; Skeel 1978:195).

In 23 cases there is no mention of a second adult being seen, although there is only one specific mention of its not being found. Nor is there any reference to other curlews coming to help mob an intruder, which they would probably do if they were close enough to hear distress calls or see agitated flight. This suggests that the birds nested far apart.

JPG -- Eggs

Figure 14. Single Eggs of, from left to right, Eskimo Curlew, Whimbrel and Long-billed Curlew. The label for the Eskimo Curlew egg indicates that it is one of two collected on 23 June 1863--apparently a transcribing error because MacFarlane gave no such data. Clark Sumida.

The incubating bird "was seen to get off the nest," sometimes, at least, flying when the searchers were still some distance away. In one case (#2346) MacFarlane mentions that the female remained within 50 or 60 yards of her nest even when shot at. He also noted that "when pursued, she gave utterance to a rather harsh scream, quite different from the usual note of the species."

Nests with eggs were reported for the following periods: 1862: 24 June (2 nests); 1863: 13 June-July (5); 1864: 16+ June-12 July (15); 1865: 16-30 June (13); 1866: 8-20+ June (3).

For 1864 a spread of at least two weeks in the hatching period is indicated. "Considerably" or "largely developed" embryos are dated 28 June, 5 and 12 July (#2457, 2373, 2346). On 12 July the two remaining eggs in one nest were apparently pipping and young were caught from another (#2344, 2368). In 1865 a sample of four nests suggests a shorter period: eggs with "well developed embryos" on 24 June, two broods seen on 29 June (one "a few days of age") and eggs apparently pipping on 30 June (#3293, 3534, 3535, 3578). In the same year "young birds of Numenius Borealis....were met with" on 15 July. In 1866 #4922 had eggs with "very large embryos" about 20 June. It would appear that the peak of hatching is sometime during the last week in June and the first two weeks of July.

Although downy young of this species have never been described, MacFarlane did collect one about 5 July and another sometime in July, 1864. They apparently never reached the Smithsonian.

There is no evidence for Mowat's (1984:53-54) claim that "before the young were even out of their natal down, the adults drew together in enormous flocks and flew away." With Arctic-nesting shorebirds, the longer the migration, the greater the likelihood that one parent (male or female, depending on the species) will leave the young before the other, but not before the young can fly (Myers 1981:195).

Foxes were a major predator in the vicinity of the Anderson River and the Eskimos were adept at snaring incubating curlews and other birds. In one case, a Snowy Owl took a snared Golden Plover before it could be retrieved.

MacFarlane's extreme dates of curlew occurrence on the breeding grounds near Fort Anderson were 27 May 1865 and 2 August. In recent years there have been sightings for 18 May 1964 and 15 August 1982.

MacFarlane also gave a status report on breeding populations for each of the first four years during his cross-country trip to Franklin Bay and back:

1862 June 24: "They were very numerous in the Barrens."
1863 June 26: "Not very scarce-numerous I should say they are-in these 'Barrens. "'
1864 June 30: "Curlews were not so numerous as on former occasions."
1865 June 29: "Curlews....were even scarcer than last year."

These fluctuations apparently did not reflect the status of curlews throughout the region as a whole' particularly the area covered by his Eskimo traders. The number of clutches and broods he noted for each of the four years is: 2, 5, 15 and 13, respectively.

There may be another indication of the relative abundance of shorebirds nesting in MacFarlane's country during the 1862-1866 period-the numbers of clutches that he and his crew found or traded for with the Eskimos and Indians. By this criterion' using MacFarlane's totals' the most common shorebirds were: 1) Lesser Golden Plover (170 sets of eggs); 2) Red-necked Phalarope (70); 3) Eskimo Curlew and Lesser Yellowlegs (30); 4) Semipalmated Plover, Least and Buff-breasted sandpipers (20). Ease of finding nests is a complicating factor in this comparison.

To document the curlew's abundance on the breeding grounds' Mowat (1984:52) quotes an Inuk, in part: "'It was told they were so many on the tundra it was like clouds of mosquitoes rising in front of a walking man. Their nests and eggs were in every tussock of grass.' " However, the Eskimo Curlew was not colonial and MacFarlane's finding of only 30 nests in five years does not suggest such densities.

Migration: By far the largest segment of the Eskimo Curlew population began its southward journey by migrating east, possibly from Siberia and certainly across Alaska, the Northwest Territories and the tip of Ungava, Quebec, before turning south down the east coast of Canada. While there are records of flocking in Alaska, nothing is known about resting areas between there and Hamilton Inlet, Labrador-a distance of more than 2400 km (1500 mi.). In Labrador the birds concentrated along a strip of shoreline less than 160 km (100 mi.) long and probably not more than 10 km (6 mi.) wide.

At Cartwright Harbour, Labrador, the first birds arrived as early as 28 July and they regularly appeared in the first week of August. Usually they stayed in large numbers through the month but we do not know whether individual birds stayed that long or whether there was a steady turnover. Final departures usually took place during the last two weeks of September and curlews in October were a rarity. In migration the birds flew high, frequently changing flock shape and flight altitude.

As for predators on migration, Audubon found curlew remains below a Gyrfalcon nest near Bradore, Quebec, and Coues watched a Merlin foraging among immense flocks of curlews in Labrador.

The birds may have followed both shores of Newfoundland after taking off from Labrador and the north shore of the Gulf of St. Lawrence in eastern Quebec. There are suggestions that stopovers even as far north as lies de la Madeleine, New Brunswick, Nova Scotia and Prince Edward Island were storm-related. Certainly the curlews paid little attention to the Atlantic coast of the United States unless head-on storms turned them westward. When this occurred, Cape Cod and Nantucket, Massachusetts, reaching out into the sea as they do, were their first landfall. However, migrating curlews and adverse storms seldom coincided-about once every 10-15 years in the 1800s and, even then, within a brief period-26 August to 5 September. The flights that landed in 1863 and 1881 were probably unique in their magnitude. George Mackay reported large flights in five years and no curlews at all in ten on Nantucket between 1858 and 1898.

A minor fall route followed Hudson and James bays, probably across southern Ontario and Quebec, then through Pennsylvania and New York to the Atlantic coast.

Once the birds left Labrador, their route was over the ocean, apparently east of Bermuda, with birds landing there and in the West Indies only if they flew into adverse weather. If they needed to rest during their day and night flight, they could settle onto the water. While landings were reported for the Guianas, reports are noticeably lacking on where the hordes regularly landed for the first time after a flight of 4000 to 5000 km (2500-3000 mi.). They passed through Brazil and Paraguay, some wintering in Uruguay but many more in southern Argentina, where the first birds arrived in September. Fall migration took two to three months.

Spring migration probably began in late February or in March. The route taken through South America remains a mystery although there is some evidence that Central America was used and that the Yucatan Peninsula may have been the jumping off point for a flight across the Gulf of Mexico to Texas. In March Eskimo Curlews could be found from Argentina to Nebraska. Migration may have slowed through Texas, Oklahoma, Kansas and Nebraska, although in May the birds were found from Texas to Alaska. There are no verified records for North Dakota or Saskatchewan, suggesting either an overflight to the breeding grounds or an absence of observers at the right time and place through the 1800s. From South Dakota to the Anderson River, NWT., is 3200 km (2000 mi.), not a long flight for this species.

Habitat: Like most birds these curlews used a variety of habitats in their annual travels. All were open-from the grassy "Barren Grounds" for breeding to fall concentration areas at the delta of the Kobuk River in Alaska, the "low hills, partly barren, and the rest covered with small bad-spruce" in Labrador and the "sterile mountainous tracts" of eastern Quebec. When they were not on the mud flats or sandbars, curlews preferred headlands and hills within a few kilometers of the sea. They also used old fields and closely grazed pastures in Massachusetts, Texas and elsewhere, and broad dry or marshy pampas in Argentina.

Burned-over prairies and marshes were particularly attractive to migrating curlews in Nebraska, Illinois and Massachusetts, while in Prince Edward Island, Illinois and Nebraska, they were found following the plough in wheat and corn fields. In Maine they once used a patch of clover. In Texas one bird appeared to use the same field for at least three weeks. Curlews roosted on the beaches along the coast but were rarely found near water in the Midwestern states.

Food and Feeding Habits: In coastal areas the curlews did some feeding on shore before and after roosting there overnight. A favorite food on rocky coastlines was snails but they also took worms and other invertebrates within sight. They then flew to the uplands and concentrated on the crowberry or curlew-berry (Empetrum nigrum) wherever they could find it. While feeding they moved quickly across an area, picking berries at a rapid rate, soon acquiring an undercoat of purple juice from bill to tail. In some cases this discoloration remained at least until they reached Massachusetts. While rushing along the birds kept up a continuous, low piping sound.

South of the crowberry's range (Map 5 ), curlews became largely insectivorous. Grasshoppers and crickets were important food items on the Atlantic coast of the United States. They also ate beetles, moths, ants, spiders, seeds and other berries. In Argentina, insects were a regular food.

On their way back north, the birds apparently roosted on bare pastures. As more and more land was broken for agriculture, curlews would be feeding in the plowed fields by 8 or 9 a.m. They came in high to their feeding fields, whistling softly; then they would turn and wheel, hover momentarily, drop and fly low over the ground before landing in a tight flock. During this migration, grasshopper egg pods and earthworms were favorite foods; as many as 31 locusts were found in one Nebraska bird.

In the Northwest Territories, the species fed on ants, grubs, freshwater insects and crowberries.

Other Behaviour: As noted above, Eskimo Curlews nested among several other species of shorebirds, including golden-plover. This is the species usually mentioned in the same breath with the curlew from New Brunswick to Massachusetts, Bermuda, the West Indies, Argentina, and back north through Texas to Illinois and South Dakota. But there is no mention of this association in Labrador (Newfoundland Quebec). Single northbound curlews in the 1980s were found with golden-plover in Saskatchewan and Manitoba.

GIF -- Crowberry Distribution

Map 5. Range of crowberry, Empetrum nigrum ssp. hermaphroditum, in North America. From Porsild and Cody 1980:459.

They have also been seen in Alaska flying for some time behind a Whimbrel, considered to be the most wary of the curlews. In the early 1900s, when the Doughbird population had been decimated, some stragglers associated with this larger curlew.

Flock size varied from three to as many thousands, although groups of 30 to 50 are most frequently mentioned. In Nebraska it was reported that the flocks amalgamated as spring advanced; in Illinois that they broke up. Attachment among flock members was often demonstrated under fire. The shooting of one bird was cause for the remainder of the flock to circle again and again until most, if not all, were shot.

When about to alight, they would sail to a landing, raise their wings above their backs until almost touching and then deliberately fold them, much like a Solitary Sandpiper.

At the approach of humans, migrant birds would occasionally squat, stretching head and neck out on the ground, remaining motionless until the intruder was sometimes as close as six feet. This behaviour was described by Audubon in Quebec-Labrador in 1833 and by Feltner in Texas 140 years later (in Lane & Tveten 1974:28).

Much has been written about their tameness and unwariness where man was concerned, which resulted in their extreme vulnerability. They seemed particularly bold when following the plow. At other times, they were wild, a condition sometimes associated with fine weather. On rainy days they were restless and in the air more than otherwise.

Adults and young largely migrated at different times, at least south of Labrador. On Nantucket, Massachusetts, Mackay reported that the first old birds generally arrived between 24 August and 1 September; young birds usually appeared between 8 September and 1 October. However, Audubon writes that curlews arrived near Bradore, Quebec, 29 July and left 12 August, during which time he ate "a good many," including adults and young. (Mackay advises that the method of aging involved bending the bird's leg; if it broke, it was an adult; if not, it was young )

Voice: The songs and calls of birds are difficult to describe in writing. It would appear that the Eskimo Curlew had some calls that would enable one to identify it as a curlew, but the word pictures are not easy to interpret. On the breeding grounds, MacFarlane heard a "prolonged mellow whistle." Flight calls have been rendered as: "oft repeated soft whistling note" (Audubon, Quebec); a flock sounding like "winds whistling through the ropes of a thousand-ton vessel...the jingling of multitudes of sleighbells" (Packard, Quebec); and "oft repeated, soft, mellow, though clear whistle, which may be easily imitated" (Coues, Labrador) While hovering above a blind, a Texas curlew gave "a tremulous whistle somewhat reminiscent of Long-billed Dowitchers on their nesting grounds" (Bleitz). "Before alighting, as they descended and sailed they gave a soft whistle, somewhat like the note of the upland plover" (Swenk, Nebraska).

While feeding they "kept up a continuous, low piping noise" in South Dakota (Cones) and "a chirruping whistle" in Nebraska (Swenk). When wounded or pursued "they emit a very loud harsh scream, like that of a common hen under similar circumstances" (Coues, Labrador). MacFarlane described the call of a female being shot at near her nest as "a rather harsh scream, quite different from the usual note of the species." Conditions for the following interpretations are not specified: large flocks, like "the chattering of a flock of blackbirds" (Coues, Labrador); "a tee doe dee note, usually either two or three syllables" (Bleitz, Texas); "low tremulous whistle" (Deaver and Feltner in Oberholser, Texas); and "a kind of squeak, very much like one of the cries of Wilson's Tern...only finer in tone" (Mackay, Massachusetts). Vocalizations are also said to resemble the Lesser Golden-Plover's and to be unlike those of the Whimbrel.

Sonagrams are available for the Little Curlew of Asia (which some consider to be the same species) but it is probably safe to say that no one has heard both species and that comparisons of the two would be guesswork (Boswall and Veprintsev 1985).

Hunting: Being hunted was a fact of life for the Eskimo Curlew for at least 11 months of the year. From Alaska to southern Argentina, wherever the birds touched land, whether regularly or irregularly, expectant gunners quickly gathered for the kill, some for sport, some for the market.

The reason they were so enthusiastically sought was their taste. They have been described as "the greatest delicacy of this place" (Labrador, 1766); "far surpassing any of our English game in richness and flavour" (Labrador, 1818); "delicious eating, being tender, juicy, and finely flavored" (Labrador, 1860); "considered by epicures the finest eating of any of our birds" (Massachusetts, 1892); "a table delicacy" (Argentina, 1800s); "highly esteemed by the high-livers of the cities" (Illinois, 1874). These evaluations have been attributed, at least in part, to the fact that the curlew's meat was all dark.

Their abundance and tameness made supplying the demand an easy matter. Certainly, it was not their size. Audubon gives a weight of half a pound (227 g), the same as that given for a bird shot in Scotland. There are several references to their weighing a pound, possibly when they were "white with fat." At such times some birds shot actually burst open upon hitting the ground.

Before about 1880, the demand for curlew meat did not appear great. Settlers and fishermen always took them and some were salted down for winter food. During a 13-year residence on the Labrador coast, in the 1700s, George Cartwright reported that he and his men took fewer than 500 curlews, with 109 being the largest number in one year. However, on one day in the 1870s more than 2000 curlews were estimated to be hanging in the Hudson's Bay store at Cartwright. From here they were shipped to Montreal and London for use by the company's officials.

It is also in the 1870s that reports begin of single hunters shooting 75 to 100 curlews before breakfast. The real incentive for concentrated hunting was outlined by Forbush (1916:427): "When the Passenger Pigeon began to decrease in numbers, about 1880, the marksmen looked about for something to take its place in the market in the spring. They found a new supply in the great quantities of Plover and Curlews in the Mississippi valley at that season....They were shot largely for western markets at first; they began to come into the eastern markets in numbers about 1886." Prices varied from 6 to 50 to 75 cents and, even, $1.00 per bird.

Where were these markets? Though incomplete, the following list of cities where curlews were sold suggests how widespread the demand was: Halifax, Montreal, Philadelphia, Boston, New York, Wichita, Omaha, St. Louis, Chicago and Detroit. They were also sold in the restaurants and markets of Buenos Aires, Argentina. The only record of the quantities involved was obtained by George Mackay from two of several game dealers in one city-Boston-in 1890. There were 8 barrels of Eskimo Curlews and 12 barrels of curlews and golden plover, with curlews packed 300 to a barrel and plovers 720. Shipments to Boston lasted at least from 1887 through 1896 and consisted of birds being taken in the Midwestern United States during spring migration.

How were they hunted? In the Midwest states the fields where they were known to gather were patrolled regularly and scanned with binoculars. Sometimes a gunner would put himself in a line of flight where he had only to shoot one bird from a flock to cause the remaining birds to circle again and again until most or all had been shot. He then waited for the next flock. At other times the hunter would use a horse and buggy to drive quickly near a flock on the ground, as if to pass it by, but then stop opposite it and fire into the close-packed group. A dog was recommended for retrieving wounded birds. These methods resulted in bags as large as 264 in an afternoon. There are several reports of 20 to 28 having been downed with a single shot.

On the Atlantic coast, the above methods were used where appropriate, but "still hunting" was also practiced. Curlews were easily decoyed using wooden or dead birds and any boy could whistle them down. An old New York hunter told of eventually shooting every curlew in a flock of 40 as they continued to circle his blind.

It was in Massachusetts that the largest numbers were reported killed. In the great flight of 1863 mentioned above, an estimated 7000-8000 curlews and golden plover were killed on Nantucket Island and that number would have been higher if time had not been spent in rushing off the island for more ammunition. On Cape Cod in the 1872 flight, two hunters reportedly shot 5000 curlews. In the same or another flight, a wagon load of curlews and plovers was seen. But the Midwestern states were not to be outdone. In Nebraska, hunters were known to have filled a wagon equipped with sideboards with these two species and then simply dumped the birds in a pile while they went after more.

There are also reports of curlews being killed with sticks-twice when they landed exhausted during storms at Boston and in the Barbados. Another case involved hunting them with the aid of lanterns at night as the birds roosted on the beaches of lies de la Madeleine, Quebec. They have been killed by boys using whips while plowing in Illinois and by Indians throwing sticks into dense flocks in Argentina.

Decline: In Labrador curlews apparently decreased noticeably between 1885 and 1890. In New Brunswick they were "fairly abundant" until 1890; after that they decreased "steadily and rapidly." It was impossible to measure the decline in the eastern states because there were years when the population was still high, but when storms did not occur to drive birds ashore A Texas observer reported them in immense flocks to 1875, several small flocks in 1886 and only three birds in 1905. In Nebraska, the 1870s marked the beginning of the decline, although barrelfuls were still coming to Boston markets from the Midwest in 1896. It would appear that the decline was closely associated with the disappearance of the Passenger Pigeon a decade earlier.

Noticeable declines apparently began in the Midwest a decade before they were reported in eastern Canada. It is also significant that barrels of curlews continued to be shipped to eastern U.S. markets from the west for a decade after the decline was reported there Richard Banks (1977) proposed an explanation for the first observation above, involving changing climatic conditions in the mid-1800s. "The slightly altered angle of departure from Labrador, caused by the altered wind, and the increased drift imposed on the birds by the stronger beam winds...led the birds along a flight line with a more easterly component than in previous decades, and some flocks missed South America and perished in the South Atlantic." He also suggested that deteriorating habitat and heavier hunting pressure increased the mortality of birds en route to and on the wintering grounds. Such losses between Labrador, Argentina and the Midwest, more or less balanced by production in the Arctic, could explain the earlier decline noted in Nebraska.

In the 1880s, such losses, combined with spring market hunting and lowered production through colder summers caused by volcanic ash in the air, could have brought about the decline finally noticed in the east (Banks 1977). A recent study of Arctic (65°-85°N) temperature patterns suggests that the springs (March-May) and summers (June- August) of the 1880s were the coolest of any decade between 1880 and 1980, averaging 1.5 + °C below the reference period 1946-60 (Kelly et al. 1982: 75) The same seasons for the 1890s were warmer, 0.5+°C below the reference period. These data fit Bank's proposal, although estimates based on temperature readings prior to 1880 were not available. However, a study of tree rings taken at 65°20'N on the Dempster Highway in the Yukon Territory indicated a warming trend for June-July for each decade from 1850 through 1890 (Jacoby and Cook 1981). The inference here is that, if curlew production was poor in the 1880s due to low temperatures, it should have been worse through each of the previous three decades. There is no evidence of such poor production.

Banks (1977:133) recognized problems with his suggestion, e.g., not knowing whether curlews could compensate for different winds using celestial navigation, what the actual effect of volcanic ash was on breeding, and why close associates of the Eskimo Curlew-Lesser Golden-Plover and Upland Sandpiper-are presently in nowhere near the plight of the curlew.

Nevertheless, spring market hunting through the 1880s had to be an important factor in the curlew's decline. Even at the anecdotal levels reported, it had a much more devastating effect than fall shooting on breeding populations. With no hunting at all, it is conceivable that half the curlews arriving in Labrador in the fall would die of natural causes before they reached their breeding grounds nine months later. This also means that half the birds shot in fall would probably have died of other causes had they not been shot. Furthermore, fall shooting in an average year was light in Labrador and eastern Quebec, where there were relatively few hunters, and negligible in the eastern states, except once in 10 or 15 years. On the other hand, shooting in the Midwest occurred every spring and was heavy starting in the 1880s. And, almost every brace of curlews and plovers shot in the Midwest resulted in a vacant breeding territory in the Arctic.

An adequate explanation for the near extinction of the Eskimo Curlew, but not its close associates, is still wanting.

It is difficult to visualize a practical and effective recovery plan for a species so rare, so difficult to find and completely unfamiliar to aviculturists. It may be that the first step is to acquire Little Curlews from their wintering grounds in Australia and find out what is involved in maintaining, breeding and rearing them in captivity.

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