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.
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.