Albert Barnes Commentary Job 37:8

"Then the beasts go into coverts, And remain in their dens." — Job 37:8 (ASV)

Then the beasts go into dens - In the winter. This fact appears to have been early observed that in the season of cold the wild animals withdrew into caves, and that many of them became torpid. Elihu refers to this fact as an illustration of the wisdom and greatness of God. The proof of his superintending care was seen in the fact that they withdrew from the cold in which they would perish, and that provision is made for their continuance in life at a time when they cannot obtain the food by which they ordinarily subsist. In that torpid and inactive state, they need little food, and often remain for months with almost no nourishment.