Fall migration in the Nueltin Lake region

In former times the southward migration reached the Nueltin Lake region in July (cf. Downes, 1943: 203-237), sometimes as early as the middle of the month. Suddenly the time of arrival shifted to (early) August, and has so remained. In Charles Schweder’s experience, the bucks nearly every year precede the does on the southward migration; this suggests that at least the majority of the bucks may not go so far north as the does. In a certain year the does actually appeared first in coming south. In normal years, according to Fred Schweder, Jr., the migration continues till October or November, by which time the animals have passed into the wooded country for the winter.

Charles Schweder described the general pattern of fall migration as follows. At first two or three animals will appear, then a few more, and after several days a big movement, lasting three or four days, will pass through. Thereafter the numbers dwindle, though the migration continues. Curiously enough, there is a definite retrograde movement northward into the Barrens in September—sometimes as early as the first part of the month. Then there is a final movement toward the south in November, at the time of the first good snows; the largest herds of the year may then be seen. Just how far the migration in 1947 conformed to this pattern (outlined in early August) will be seen in the following pages.

The big August movement occurs occasionally as early as the first days of the month, whereas it was delayed till the last week in 1947. About the first of August, 1943, according to Fred Schweder, Jr., a thousand Caribou swam across the mouth of Windy River in the course of an hour, and there were other thousands during a two weeks’ period. But such a large migration strikes this point only once in several years. In other years it may pass southward farther to the west, as in the vicinity of Simons’ Lake.

In the fall of 1946—the very season when the Caribou bypassed the Eskimo camps on the upper Kazan River—there were said to have been far more than the normal numbers in the Windy River area. Thousands passed in one day, about October 10. The hills about Four-hill Creek then gave Fred Schweder, Jr., the impression of “moving with Deer.” By comparison, the numbers along the Windy River in 1947 were considered by the local residents to have been below normal, however impressive they may have been to a zoological visitor. On the other hand, it seemed to Charles Schweder, during his trip down the Thlewiaza River in late August of 1947, that Caribou were still very numerous; and he reported that people along the west coast of Hudson Bay were then getting more of the animals than in previous years.

Only rarely do limited numbers of Caribou remain all winter in the Windy River area. During Charles Schweder’s years of residence there (about 1936-47) the animals had done so just once—on the Windy Hills. In 1946-47 Fred Schweder, Jr., found about 300 of them remaining all winter about the north end of Ennadai Lake. He said that the locally wintering animals are all bucks. Katello, an elderly Eskimo of the upper Kazan River, informed Charles Schweder that the Caribou used to remain there all winter, but now very rarely do so.

By the end of July, after both men and dogs had subsisted for several weeks on a diet devoid of caribou meat, an air of expectancy began to pervade the Windy River camp. The hunters roamed the Barrens or watched from some lookout post such as the Pile o’ Rocks (fig. 27). No Caribou were detected during plane trips to the upper Kazan River and return on July 31 and August 3, though their ancient, well-marked trails were visible along the ridges. It was not until August 6 that the first buck of the return movement was encountered. On the following day another animal was secured. On August 10 and 11 only a few Caribou—not over 25 in a band—were seen by Charles Schweder and Fred Schweder, Jr., from the air between the Windy and the Kazan rivers. It began to be feared that the bulk of the migration might pass somewhere to the westward. On August 13, however, at a distance of some miles from camp, Fred sighted 20 Caribou; all of them were does and fawns except for one buck. On August 17 he secured a good-sized buck (specimen No. 1065; figs. 3, 4) at Bear Slough and saw five other bucks elsewhere. Two days later Anoteelik reported a band of 13.

On August 20 Fred reported about 300 Caribou moving in our direction across the Barrens east of Lake Charles; they proved to be the advance guard of a big movement. On the same afternoon I had filmed several bucks going their separate ways on the slopes about Pile o’ Rocks and Stony Man. They were moving along somewhat hurriedly, in a manner very different from the placid grazing of sheep or cattle. One or two does with fawns also appeared in the vicinity. (The passage of a Keewatin Tundra Wolf over the same ground a short time previously had no effect, as far as I observed, on the behavior of the animals at this time.) A grander, though more distant, spectacle gradually unfolded off to the eastward, beyond Little River, where several groups, numbering from 3 to 20 or 25 individuals, were feeding quietly over the open Barrens. Their fresh dark autumn coats showed up much more conspicuously than had the cream-buff of their winter coats in June. Presently the scene became livelier, as the largest band, composed of does and fawns as well as lordly bucks, started to romp northward over the Barrens. One or more of the various kinds of insects that bring life-long misery to the Caribou may have stampeded them. This band swept past a group of half its size without at once involving it. A doe and a fawn remained lying down as the others passed.

As the eye swept farther over that lonely land, still other Caribou were disclosed singly or in groups scattered over a couple of square miles. There was no strong herd instinct as they grazed at will. Even when on the march, they straggled along, some as much as 20 to 30 yards apart. As the sun sank lower, and the black flies became less active with the dropping temperature (about 53°), a lull ensued in the movements of the Caribou.

The big movement of the fall migration finally began to materialize on Sunday, August 24. This and the next few days were filled with memorable experiences. The throngs of Caribou passing at such times around the head of Windy Bay and across the lowermost portions of Little and Windy rivers may be accounted for, in part, by the local topography (map 1). The upper part of Windy Bay, occupied by numerous islands of various sizes and extending about 5 miles in an east-west direction, opposes something of a barrier to the Caribou in their southward trek. The easiest way to overcome this barrier is to by-pass it. So the migrant herds approaching the north shore of the bay turn westward toward Little River. At a point half a mile short of this stream a rather minor proportion of the Caribou actually do essay a passage of Windy Bay. They cross an island lying very close to the north shore, then steer for a small rocky islet a quarter of a mile northwest of the mouth of South Bay. Here they get a brief respite from swimming by walking through the shallow bordering waters, then continue straight on to the rugged south shore of Windy Bay. This course is roughly parallel to, and a quarter of a mile west of, the one pursued northward or northeastward across the ice in the spring migration. The Caribou were seen to follow this water route on various days from August 24 to September 8, and again on October 7. Like the one across the ice, it is probably a regular, well-established, annual route.

The greater number of the migrants proceed along the north shore of the bay to Little River and are there confronted with a choice of various further routes. Some continue for an indefinite distance up the northeastern bank, passing Lake Charles on their right, though other animals, coming from the north, may be following this bank in the opposite direction. Probably most of the Caribou arriving from the eastward either plunge into Little River at its mouth and swim across (figs. 9, 10, 12) or pass upstream for a bare quarter of a mile and then wade across at a rapid (figs. 7, 8).

Without human interference, a large proportion of those that cross the lower part of Little River would doubtless proceed more or less directly to Windy River and cross near its mouth. But the human and canine inhabitants of the Windy River post seem to exert a strong influence in deflecting the Caribou northwestward along several more or less parallel ridges that rise to a maximum height of 40 or 50 feet. These are Little River, Middle, and Camp ridges (map 1). Many animals follow the first of these to its northwestern end, then cross a bog and ascend the Middle Ridge. Some cross the southeastern end of Little River Ridge, scramble down its steep sides by strongly marked trails (fig. 2), and then move across the Eastern Bog to the Middle Ridge. But when they reach the summit, they can see the post directly ahead, and generally hurry off northwestward along the ridge. Presently some may cross the Camp Slough (fig. 13) to the Camp Ridge and then proceed either westward or northwestward. The Caribou have a strong predilection for following the treeless summits of the ridges wherever they are available and extend in a more or less desirable direction. On reaching the vicinity of the Bear Slough, where the three ridges are interrupted or peter out, the animals doubtless turn more or less southwestward to make a passage of Windy River at various points above its mouth. Under the conditions outlined above, it is obvious that some of the finest opportunities for close-range observation and photography lie at the two well-established crossings near the mouth of Little River.

On the dark and drizzly morning of August 24 (temp. 47°-48°) I noticed a number of Caribou, in groups of 2 to 20, traveling northwestward along Middle and Little River ridges. This indication of general activity enticed me to the top of the latter, whence I had a view of perhaps 8 or 10 animals scattered over the Barrens beyond Little River. Several were lying down just beyond the summit of a ridge between the river and Glacier Pond, so that little more than their antlers was visible. With the idea of finding out how closely I could approach these resting animals, I waded knee-deep across a rapid about 100 feet in width, and worked my way up the opposite slope until I once more caught sight of the tips of several antlers. Under cover of a rock and some dwarf birches, I crept ahead on hands and knees, with a miniature camera at the ready. I had arrived within 50 yards when the nearest buck got to its feet and stood looking at me. In hopes of photographing the rest while they were still lying down, I rose to my knees and hastily exposed the last bit of film in the camera. Still there was no immediate reaction on the part of the Caribou. Fortunately there was a cross wind. The first buck was so little alarmed that it leisurely sprinkled the ground. But presently it turned and walked off, presumably giving some signal of voice or posture (such as an erect tail) to the rest; for they got to their feet, not the half a dozen I expected, but half a hundred of them! Though they trotted off toward Windy Bay, they paused within a hundred yards and turned to stare at me. Several more relieved themselves as the first buck had done. By this time I saw that some of the Caribou, including a little fawn, were carrying their tails quite erect, as an expression of suspicion or a signal of alarm. Evidently a majority of the band were bucks, but there were some does, with foot-long horns, and their fawns. On my way back to camp I noticed several groups of Caribou swimming across Windy Bay; perhaps they included the very animals I had so recently disturbed.

In the early afternoon it became evident that a further northwesterly movement was under way along the ridges between camp and Little River. The animals had doubtless made the passage of the river near its mouth. I followed some of them to a bog at the upper end of Little River Ridge, where I began to film several bucks and a lone, inquisitive, one-horned doe. While the latter was approaching me within a hundred feet, I caught a movement out of the corner of my eye, and all at once the bog seemed full of Caribou. There were 75-100 of them, chiefly bucks, and not more than 50 yards or so distant across the open bog. They presently moved on, without haste, and ascended the Middle Ridge.

Several hours later about 50 more Caribou passed through this bog. Then a band of 17 came along, composed chiefly of does and their fawns, with a couple of young bucks; they did not even turn their heads in my direction as I stood in the open 50 yards away. Eventually a herd of about 150 (the largest I saw during the whole season) passed along the well-worn trails on the summit of the Middle Ridge. It seemed to include all sexes and ages, with possibly a majority of does and fawns; bringing up the rear was a limping patriarch with huge antlers, a heavy mane, and a lingering winter coat.

During the remainder of the afternoon several other groups appeared in that general area. About 15 individuals descended Little River Ridge (fig. 2) to the Eastern Bog, but retraced their course after coming close to several of us; they were mostly does, with four fawns and a few bucks. Another band, of all ages and sexes and numbering perhaps a hundred individuals, crossed at the rapid on Little River. The temperatures that had prevailed during this day’s marked migratory movements varied from about 45° to 50°. They were low enough to keep the black flies completely in abeyance, and the mosquito season was virtually over. Although I noticed none of the parasitic flies, possibly enough of them were present to keep the Caribou moving actively against a moderate to brisk northerly wind. Now and again a big buck could be seen fairly jumping out of its skin with the vigor of vibrating its sides to shake off the tormentors.

On August 25 (the second day of the big movement) I watched and filmed the pageant of Caribou migration from the southwestern bank of Little River. The turfy slopes of the Barrens, carpeted with low ericaceous shrubs, mosses, and reindeer lichens, and dotted here and there with little thickets of dwarf birch, spruce, and tamarack, stretched invitingly before me. Temperatures ranging from 40° to 51°, with a brisk northwest breeze sweeping down the river, happily suppressed most of the black flies.

The Caribou came along at intervals from the eastward, in bands up to 75 strong, either to make the passage of the river or to continue upstream along the opposite ridge. A small number might make the crossing in one or two files, but one of the larger bands might spread out widely in the shallow rapid. One of the photographs (fig. 7) shows approximately 75 Caribou going divergent ways at this rapid: about 20 passing upstream along the ridge on the far side, including some pausing to feed on the low vegetation; 8 or 9 moving down the slope of the ridge to the water’s edge; about 10 bucks, 16 does, and 6 fawns making the passage of the river; and about 13 arriving on the near shore and pausing to feed. The adults were able to step across in the swift water, while the fawns swam part of the way. The bucks were apparently in the minority again on this day.

One group of some 40 does and fawns, after swimming the river near its mouth, came hurrying along the ridge in close array directly toward my station, and did not take alarm until they had arrived within 100 feet. Then they turned tail and, each with its flag erect, beat a hasty retreat. The maneuver made a scene of considerable charm and interest. While I was filming a dozen Caribou in the Eastern Bog from the Middle Ridge, a stray fawn came up and halted for some seconds within a rod of me. The bewildered look in its big eyes was comical though pathetic. In presently dashing on, it passed within a dozen feet.

Late in the afternoon Fred Schweder, Jr., reported about a thousand Caribou, in various bands up to 100 strong, crossing Little River here and there a mile or so above its mouth. They were traveling southwest.

Retrograde autumnal movement

It would doubtless be difficult to find, among other animals, any exact parallel to this curious feature of caribou migration. According to Charles Schweder, it takes place in the Nueltin Lake region in September—sometimes as early as the first of the month. Herds up to 200 strong may then be seen moving northward, but generally the numbers are smaller—say 10 to 30 in a band. Some of the more notable autumnal movements toward the north, as reported by Charles, were the following: at Simons’ Lake in 1936 and again in 1938, when herds of fat bucks were streaming past for a month and a half; likewise at Josie’s Bay in 1940; and through the Windy Hills and across Windy River in 1943. Fred Schweder, Jr., said that most of the animals, in returning northward at this season, cross Windy River 4 miles above its mouth or Windy Bay 4 miles from its head; comparatively few pass the mouths of Windy and Little rivers. He remarked further that it is mostly bucks, with few does and fawns, that make the passage on Windy Bay.

More or less evidence of such a movement toward the north in 1947 has been presented in preceding pages, in the notes for September 6, 7, 11, 14, 20, 24, and 28, October 1, and even October 23. The numbers observed so involved on each of these days varied from a solitary buck or a doe with a fawn to about 300 of the animals. On some of these days, however, other Caribou were observed making their way toward the south. It is thus obvious that there was no universal impulse among the Caribou of a given area to move simul­taneously in a certain direction.

The general weather conditions on the nine above-mentioned days may be summarized as follows. Every day but one was largely or wholly cloudy; snow falling on three days, but ground bare on other days; wind predominantly from the north; extreme temperatures, 26° and 61°; mean daily average, 37.5°. Whether or not there is significance in the matter, it appears that on those days within the period extending from September 6 to October 1, when the Caribou were not definitely observed moving northward, the winds were less likely to be northerly. Furthermore, within this period there was never enough snow to interfere appreciably with the animals’ feeding on the ground lichens of the Barrens.

By October 6 there were 6 inches of snow on the ground, and on the following day 200 Caribou swimming southward across Windy Bay may have marked the beginning of the final movement into the timbered country. It appears possible that a considerable fall of snow may have a definite influence in inducing the Caribou to retreat from the Barrens.

On a trip from Windy River north to the Kazan River region in September, 1946, Charles Schweder found, during the first 45 miles, that the Caribou were moving north; at the Kazan they were moving south, although some were merely loitering. Northwest of the Kazan, the animals were taking a westward course. During the latter part of his return trip to Windy River, 11 or 12 days later, they had reversed the previous direction and were traveling south.

For such a distinct and regular feature in the life cycle of the species as the retrograde autumnal movement there must be some biological explanation. Several possible factors appear reasonably clear. Perhaps we may consider the Barren Grounds the true and preferred home of Rangifer arcticus, from which a proportion of the population is driven during part of the year under stress of insect attacks or shortage of food. When the animals begin to enter the woods in August, there is no shortage of food; thus an insect-induced frenzy may possibly be regarded as a potent force driving them southward. In September a state of comparative peace descends upon the caribou world: the current crop of adult insects has subsided; the larvae of warble and nostril flies have not attained the formidable size of the following spring and perhaps are not yet causing any severe discomfort; little or no snow covers up the food supply; the lakes and rivers, still unfrozen, offer a ready way of escape from pursuing Wolves; moderate or even balmy weather gives nature a pleasant mood. In short, both man and beast may well look upon early autumn as the very finest time of year both on the Barrens and in the adjacent wooded country.

Under these circumstances a definite retrograde movement out of the wooded country in September on the part of many Caribou must indicate their preference for the Barrens at this season. In any event, the movement begins just after the insect menace has subsided to a negligible stage. Possibly another inducement for retreating from the wooded country in the early fall is the dearth of open areas in which the animals may spend their resting periods, in comparative safety from Wolves. It is only after the freeze-up that the surfaces of the lakes and rivers supply this desideratum. This condition lasts from November to June—precisely that part of the year in which the Caribou are present in the wooded country in the greatest numbers.

But by November what are the conditions on the Barrens? The weather has become severe; snow has covered up a large part of the ground lichens; tree lichens are not to be had. And so at this season, with the coming of the first heavy snows, there is a final movement out of the Barrens into the shelter of the woods, leaving only a minority of the animals to face a bleak and bitter winter in the open country. The biggest herds of the year may then be seen passing southward. A few bucks are said to remain during most winters in the Windy River area.

Far to the westward, toward Great Slave and Great Bear lakes, the retrograde movements are somewhat different and more complicated (Clarke, 1940: 96).

“Mr. Carl Buchholz, of Churchill, describes the caribou migration at the 60th parallel, north of Churchill, as a southward migration in August, northward in September, and then south in the autumn” (Clarke, 1940: 97). (See also the next paragraph.)

Fall migration in the Churchill region

The following notes for 1947 were kindly furnished me by Angus MacIver. He reported large numbers of Caribou moving southward across Caribou Creek (25 miles south of Churchill) about November 10, a day after the local freeze-up. He would then see thousands in a day. Prior to that time (perhaps in September?) there had been two “runs” to the northward and northwestward; these presumably represented the normal retrograde migration in the fall. The herds engaged in these two northerly movements must have previously passed southward farther inland. He reported also that the rutting season this year had commenced a little later than the usual October 15.

References on migration.—Dobbs, 1774: 20, 22; Hearne, 1795: 39, 40, 56, 66, 74, 85-87, 286, 299; Franklin, 1823: 241-242; Sabine, in Franklin, 1823: 667; Richardson, “1825”: 328-329, and 1829: 242-243; Godman, 1831, 2: 283-284; John Ross, 1835a: 328, 330, 337, 376, 390, 529-530, 628; J. C. Ross, in John Ross, 1835b: xvii; Richardson, in Back, 1836: 498; Simpson, 1843: 76, 196, 233, 277, 301, 320-321, 328, 386; Rae, 1850: 93; Richardson, 1852: 290, 296; Rae, 1852a: 79; J. Anderson, 1857: 326, 328; Murray, 1858: 203; Richardson, 1861: 274, 275; B. R. Ross, 1861: 438-439; Osborn, 1865: 223-224, 226; Kumlien, 1879: 54; R. Bell, 1881: 15C; Caton, 1881: 108; Gilder, 1881: 196-197; Nourse, 1884: 235, 356; Schwatka, 1885: 77-79, 83; Boas, 1888: 502; Collinson, 1889: 244, 290; Pike, 1917 (1892): 48-49, 50, 89-91, 101, 174, 204, 209, 220; J. B. Tyrrell, 1892: 128-130; Dowling, 1893: 103, 107; J. B. Tyrrell, 1894: 442, 1896: 13, 63, and 1897: 10, 19, 21, 49-50, 76, 124, 140, 142, 165; Russell, 1895: 48, and 1898: 88, 226; Whitney, 1896: 157, 238, 241; Lydekker, 1898: 48; J. W. Tyrrell, 1908 (1898): 77-78, 80; Jones, 1899: 368, 374; Hanbury, 1900: 66-67, 69, 71; A. J. Stone, 1900: 50, 53; W. J. McLean, 1901: 5, 6; Elliot, 1902: 259, 260, 274-275; Preble, 1902: 42; J. W. Tyrrell, 1924 (1902): 26, 31; Hanbury, 1904: 10, 30, 32, 34, 58, 93, 108, 120, 121, 139; Hornaday, 1904: 137; Stone and Cram, 1904: 52; MacFarlane, 1905: 683-685; J. A. Allen, 1908a: 490; Amundsen, 1908, 1: 97, 102-106, 200, 247, 326-329; Preble, 1908: 137-139; Cameron, 1912: 127; Wheeler, 1912: 199-200; R. M. Anderson, 1913a: 6, and 1913b: 502; Stefánsson, 1913a: 94-96, 99, 100, 103, 106, 1913b: 203-204, 224-225, 263-265, 269, 294, 348-350, and 1914: 39, 41, 54; Chambers, 1914: 93; Hornaday, 1914, 2: 101-104; Wheeler, 1914: 58; Harper, 1915: 160; Camsell, 1916: 21; Thompson, 1916: 99-101; Kindle, 1917: 107-108; Camsell and Malcolm, 1919: 46; Whittaker, 1919: 166-167; Buchanan, 1920: 105-108, 128-129; Hewitt, 1921: 60-63; Stefánsson, 1921: 401; Jenness, 1922: 15, 17, 25-26, 125; Blanchet, 1925: 32-34, and 1926b: 46-48; Mallet, 1926: 79; Preble, 1926: 137-138; Rasmussen, 1927: 54, 214-217, 246; Birket-Smith, 1929 (1): 51, 56, 101, 106; Seton, 1929, 3: 122, 125-128; Blanchet, 1930: 49-52; Critchell-Bullock, 1930: 58, 192-196; Hoare, 1930: 13, 14, 16, 21, 22, 27, 31, 33, 36-38; Kitto, 1930: 87; Mallet, 1930: 20-23, 27; Jacobi, 1931: 80-84, 192-210; Harper, 1932: 30, 31; Munn, 1932: 58; Sutton and Hamilton, 1932: 79, 81; Weyer, 1932: 40; Birket-Smith, 1933: 91-94, 112, 118; Ingstad, 1933: 34, 134-135, 156-159, 161, 163, 225, 229-231, 280, 291, 293, 296, 324; Weeks, 1933: 65; R. M. Anderson, 1934a: 81, 1937: 103, and 1938: 400; Hornby, 1934: 105-107; Birket-Smith, 1936: 91; Hamilton, 1939: 244-247, 359; Murie, 1939: 244; Clarke, 1940: 8-9, 11, 85-100; G. M. Allen, 1942: 298-299; Soper, 1942: 143; Downes, 1943: 215, 221, 224, 249, 250, 253-256, 260; Manning, 1943a: 52, and 1943b: 103; Porsild, 1943: 389; Soper, 1944: 248-249; Wright, 1944: 186, 190; Gavin, 1945: 227-228; R. M. Anderson, 1947: 178, and 1948: 15; Manning, 1948: 26-28; Rand, 1948a: 212, and 1948b: 149; Banfield, 1949: 478, 481; Harper, 1949: 226-230, 239-240; Banfield, 1951a: 6, 9-12, 28, and 1951b: 120; Anonymous, 1952: 267; Barnett, 1954: 96, 103.

Summation of Geographical Distribution

The localities from which hitherto unpublished notes on Rangifer arcticus arcticus are presented in this paper include the following. Keewatin: Nueltin, Windy, “Highway” (at source of Putahow River), and Ennadai lakes; Little Dubawnt, Kazan, Red, Windy, Little, and Thlewiaza rivers; between Eskimo Point and Baker Lake. Manitoba: Nueltin (southern part), Nejanilini, Reindeer, and Split lakes; Seal River; Churchill; Cape Churchill; “Little Barrens” south of Churchill; between Churchill and Knife Lake; Caribou Creek, 25 miles south of Churchill. Saskatchewan: small lakes southwest of Reindeer Lake; lakes south of Lake Athabaska. Details as to occurrence and status in these localities are supplied on other pages.

The Caribou have been so thoroughly distributed over the approximately 300,000 square miles of the mainland Barren Grounds between Hudson Bay and the Mackenzie Valley that it is fairly safe to say that there is scarcely one square mile in this vast territory that has not been trod by the animals during the past century. See maps by Preble (1908: pl. 19), Seton (1929, 3: 60), Clarke (1940: figs. 3, 4), Banfield (1949: 479), and Anonymous (1952: 267).

The appended annotated bibliography supplies, in abstract form, most of the hitherto published information on the geographical distribution of Rangifer arcticus arcticus. In its preparation I have included records of Caribou from the Arctic islands north to Lancaster Sound, Barrow Strait, Viscount Melville Sound, and McClure Strait—all approximately in latitude 74° N. This has been done as a matter of having a convenient, well-defined regional boundary, not with any conviction that arcticus has ranged so far to the north in the more westerly islands, especially in recent years, when it is said to have become restricted to the southern fringe of the islands (Clarke, 1940: 98; R. M. Anderson, 1947: 178; Banfield, 1949: fig. 1). The islands north of latitude 74° are doubtless the exclusive domain of Rangifer pearyi. It is possible that this species may also occur to some extent on Banks, Victoria, Prince of Wales, and Somerset islands. The typical R. a. arcticus, as currently recognized, ranges eastward to Baffin, Salisbury, Coats, and Southampton islands and to the western shore of Hudson Bay. (The animals of the last three islands may be distinct insular forms.) The southern limits of the winter range in northwestern Ontario, central Manitoba, northern Saskatchewan, and northeastern Alberta have been discussed in preceding pages. On the west the range extends to the Mackenzie Delta (formerly), Great Bear and Great Slave lakes, Wood Buffalo Park, and Lake Claire. The timbered country (Hudsonian and Canadian Zones) is practically entirely deserted by the Barren Ground Caribou in mid-summer. At this season, in Keewatin at least, the animals tend to draw away also from the southernmost portions of the Barren Grounds.

References.—Since practically every paper in the entire bibliography presents some data on geographical distribution, only a few, containing more than an average amount of new or summarized information on the subject, have been selected for inclusion in the following list of references: Hearne, 1795; Franklin, 1823; Lyon, 1824; Franklin and Richardson, 1828; Simpson, 1843; Pike, 1917 (1892); Russell, 1898; Preble, 1902; Hanbury, 1904; Amundsen, 1908; Preble, 1908; R. M. Anderson, in Stefánsson, 1913b; Stefánsson, 1913a, 1913b, and 1921; Hewitt, 1921; Jenness, 1922; Rasmussen, 1927; Seton, 1929, 3; Blanchet, 1930; Critchell-Bullock, 1930; Hoare, 1930; Jacobi, 1931; Clarke, 1940; Manning, 1943a; Wright, 1944; R. M. Anderson, 1947; Manning, 1948; Banfield, 1949 and 1951a.

Distributional maps.—Grant, 1903: map following p. 196; Preble, 1908: pl. 19; Dugmore, 1913: 138; Hewitt, 1921: 57; Seton, 1929, 3: 60, map 2; Jacobi, 1931: 77, fig. 17; R. M. Anderson, 1934b: 4062, fig. 6; Murie, 1939: 241; Clarke, 1940: figs. 3, 4; Banfield, 1949: 479, fig. 1, and 1951a: figs. 4-10; Anonymous, 1952: 267.

Ecology

Habitats

Within their natural range the Caribou apparently resort to practically every type of terrestrial and aquatic habitat (other than cliffs and precipices). On the Barren Grounds proper they frequent the open summits and slopes of the ridges, the dwarf birch thickets, the sedge bogs, and the peat bogs. Their trails traverse all the upland spruce and tamarack tracts, the wooded muskegs, and the willow thickets along the rivers. In the summer and fall they swim the rivers and the narrower lakes, and during the winter and spring they cross these on the ice. They do not avoid rapids; in fact, they seek the shallower ones as fords, and they swim the deeper ones (cf. Clarke, 1940: 88). They also cross the tundra ponds on the ice, but probably walk around these smaller bodies of water, as a rule, when they are not frozen. While they may prefer to approach the river crossings over open slopes, they do not hesitate to maintain trails through the dense thickets of willow on the banks.

The winter habitat of the major part of the Barren Ground Caribou population comprises the Hudsonian and upper Canadian Zones. This forested habitat is characterized by sparser and smaller timber in the Hudsonian Zone and by denser and taller timber in the Canadian Zone. Important among the features of this winter habitat are the frozen surfaces of the lakes and rivers, where the Caribou are wont to congregate for their daily periods of rest (cf. Mallet, 1926: 79; Ingstad, 1933: 86).

Trails

The favorite migratory highways are the long, sinuous ridges that stretch across the Barren Grounds in a sufficiently approximate north-south direction to serve the needs of the Caribou. Here their age-old trails are particularly in evidence and may even be detected from the air. A single small ridge may bear half a dozen or more such trails (fig. 1), roughly parallel but anastomosing at frequent intervals. They probably change but little from generation to generation. They provide the smoothest courses available, avoiding rocks and shrubs and traversing intervening bogs at the most suitable points. The summits of the ridges constitute vantage points from which the animals may keep a wide lookout for Wolves and human enemies, and on which they may obtain the maximum benefit from fly-deterring breezes. Man himself is glad to utilize these trails, whether on the Barrens or in the timber tracts, wherever they lead in a direction he desires. They are kept open by the hurrying feet of hundreds or thousands of Caribou every year.

Along a well-used trail extending through low Barrens near Duck Bay, I found a certain grass (Agrostis scabra) growing. I did not recognize or collect it elsewhere during the season. Is this perhaps like certain other species, such as Juncus tenuis (fide Dr. Edgar T. Wherry) and Eleocharis baldwinii, in curiously thriving on beaten paths?

When the Caribou arrive at some lake or river, they generally follow the shores for a greater or lesser distance, seeking either a way around or a suitable crossing-place. The trails thus formed are generally on the nearest ridges rather than on the immediate shores. Their direction, as they conform to the winding shores, may diverge very widely from the desired migratory course.

In many parts of the Barren Grounds there must be as many as 10 linear miles of caribou trails to every square mile of territory. Even if there were only one mile of such trails to each square mile, the total, on the Barrens of Keewatin and Mackenzie alone, would equal or exceed all the railway mileage in the United States.

In contrast to the narrow ridges, the broader hilltops in the Barrens offer such freedom of movement to the Caribou that trails are much less likely to be formed in such places, even when they are frequented by large numbers of the animals. Thus I found the broad summit of Josie’s Hill practically without well-defined trails, despite the regularity with which many migrant bands resort thither. In feeding or traveling over such an area, there is no occasion for restricting themselves to a narrow course. In crossing from one ridge to another through an intervening bog, the animals may leave numerous scattered and temporary trails in the dense sedge growth to mark their passage (fig. 13). On the uniform surface of such a bog, as on the broad hilltops, there is no need to confine their steps to any particular course.

It might be supposed that the Barren Ground Caribou would have some reluctance in entering thickly wooded tracts, where Wolves naturally have a much better chance of a close approach than on the open Barrens. As already stated, however, their trails may be found more or less throughout the spruce and tamarack growth in the Windy River area. One of these tracts, covering probably several square miles on the west side of Four-hill Creek, is fairly crisscrossed with trails. At deep dusk on October 2, while several of us were skinning a Black Bear in this thick timber, about five does and fawns trotted up quite close to us. Perhaps they were on their way to the open Barrens to pass the night. While wintering in the forested Hudsonian Zone, the animals may spend their nights as well as their diurnal resting periods on the frozen lakes and rivers.

Fred Schweder, Jr., says that Caribou are somewhat fearful of sand hills or eskers, and that he has never seen one lying down in such a place; he believes this is because the Wolves frequent the eskers in summertime. On the other hand, Mr. G. W. Malaher spoke of a long esker that extends down the west side of Nueltin Lake and far to the southward; this, he said, forms a migration highway for the Caribou.

References on habitats and trails.—J. B. Tyrrell, 1892: 129, and 1895: 445; W. J. McLean, 1901: 6; Blanchet, 1925: 33, and 1926a: 73, 96-97; Mallet, 1926: 79, 80; Seton, 1929, 3: 100-102, 122, 127-128; Jacobi, 1931: 186-187; Ingstad, 1933: 86; Murie, 1939: 246; Manning, 1948: 26-28; Rand, 1948a: 212; Harper, 1949: 226, 228; Banfield, 1951a: 3.

Influence of weather on distribution

In the section on Migrations the meteorological conditions in 1947 have been reported for any possible bearing they may have had on the daily movements of the Caribou, particularly during the fall migration. The temperature has an important effect on the activity of the insect pests (see Influence of insects on distribution) and thus, to a certain extent during summer and fall, on the behavior and probably the distribution of the Caribou.

Low winter temperatures on the Barren Grounds do not appear to be a factor of prime importance in the seasonal distribution of R. a. arcticus. “Some individuals and small herds remain in the northern part of the range at all seasons” (R. M. Anderson, 1947: 178). Peary’s Caribou (R. pearyi) inhabits the more northerly Arctic islands throughout the year, without engaging in such extensive migrations as its relative to the south.

The forceful winds that blow over the Barren Grounds so much of the time are of distinct benefit to the Caribou during the summer in abating the very serious scourge of flies. If other things were equal (as they are not), this factor alone would make the Barrens a more favorable summer habitat than the forested country. (See Retrograde autumnal movement.) Air movements of similar strength during the winter must, through the wind-chill factor (cf. Siple and Passel, 1945), make life so much the harder for any living being; on the other hand, they tend to sweep the ridges bare of snow, thereby making readily available the Caribou’s principal winter food of reindeer lichens (Cladonia spp.)

References.—Armstrong, 1857: 479; Critchell-Bullock, 1930: 192, 194-196; Hoare, 1930: 33; Jacobi, 1931: 193, 195; Clarke, 1940: 96, 99; Banfield, 1951a: 27-29.

Influence of food supply on distribution

The strong winter winds on the Barrens affect the Caribou in still another way. While they pack the snow so firmly that man may dispense with snowshoes, this condition naturally increases the difficulty that the Caribou experience in pawing through the snow to reach the lichens that are covered by it. The limited grazing capacity of such areas as are laid bare by the wind may force a reduction in the wintering population. Although the snow in the timbered regions to the south covers virtually the whole surface of the land, it is evidently less compact and so offers more favorable feeding conditions than the areas of hard-packed snow on the Barrens. (Charles Schweder states that Willow Ptarmigan will fly out of the Barrens to spend the night in tracts of timber, where the snow is softer and thus more suitable for the nocturnal burrows of these birds.)

Another apparent inducement for resorting to the tracts of timber in winter is the abundance there of tree lichens, such as Alectoria and Usnea (cf. Richardson, 1829: 243; J. B. Tyrrell, 1894: 441; Dix, 1951: 287), upon which the Caribou may feed without regard to snow conditions. (See also Retrograde autumnal movement.)

Reindeer lichens (Cladonia spp.) and doubtless other lichens are of such slow growth that forest fires may deprive the Caribou of this indispensable food for a period of years. According to Mr. G. W. Malaher, the recent burning of a large area north of The Pas may have deflected the animals toward the southeast, causing them to extend their migration to an abnormal distance in that direction. For a similar reason in years past, according to Pike (1917 [1892]: 50), they avoided “great stretches of the country” near the Mackenzie River, and also on the south side of Great Slave Lake. A quarter of a century after Pike’s time, Dogribs reported that Caribou had not come to the lower Taltson River for several years, “because the timber had been burned off” (Harper, 1932: 30). Some years ago, extensive fires in Manitoba were said to have been deliberately set by prospectors with the aim of exposing the underlying rock.

Charles Schweder believes that the Caribou show a certain predilection for rocky places, owing to the more luxuriant growth of lichens there.

References.—Richardson, “1825”: 328-329; Bompas, 1888: 24; Pike, 1917 (1892): 50; Wheeler, 1914: 60; Blanchet, 1930: 52; Jacobi, 1931: 192, 194, 195; Harper, 1932: 30; Ingstad, 1933: 34, 161, 163; Hornby, 1934: 105; R. M. Anderson, 1938: 400; Clarke, 1940: 100, 106-107; G. M. Allen, 1942: 299; Downes, 1943: 261; Porsild, 1943: 389; Wright, 1944: 186; R. M. Anderson, 1948: 15; Banfield, 1951a: 5, 11, 27-29.

Influence of insects on distribution

It is quite possible that the blood-sucking mosquitoes (Aedes) and black flies (Simulium) and the parasitic warble flies (Oedemagena) and nostril flies (Cephenemyia) have a definite and important influence on the extent and dates of caribou migration.

As far as I am able to judge from my own experience, mosquitoes are more or less equally numerous and ferocious in the Canadian, the Hudsonian, and the Arctic Zones of the Northwest. Naturally the season begins earlier in the more southerly localities. In two seasons (1914, 1920) at the western end of Lake Athabaska they began to be troublesome about the middle of June, whereas at Nueltin Lake this stage was reached about the first of July. In the Athabaska and Great Slave lakes region (Canadian and Hudsonian Zones) I have never had occasion to regard black flies as serious in respect to either numbers or ferocity; but there is universal agreement that conditions are vastly different and worse on the Barren Grounds. At Nueltin Lake the Simulium hordes become troublesome at approximately the same time as the mosquitoes. Toward the end of August there is a merciful diminution in the numbers of both mosquitoes and black flies on the Barrens, and after the first of September they may be practically disregarded, except on an occasional day of unseasonable warmth.