In the course of nature's year, there is a shifting balance between predator and prey. During the colder months, when food is scarce and heavy snows or ice impair mobility, the hunters have a decided advantage.
Across the north, wolf packs feast on elk, moose and deer that are weakened by the elements and stranded by the weather. In more moderate climes, owls, hawks, coyotes and fox enjoy a similar advantage; though their prey (cottontails, voles, quail) may den up during severe weather, they must eventually seek food and, when they do, these patient and well-equipped hunters are waiting. Flocking birds, especially gregarious during the winter months, are easy targets for falcons and accipiters.
Winter is, indeed, the culling season, ensuring that prey populations remain in check. And, despite the brutal conditions, it is often a less challenging season for many of the predators. But spring will arrive, greenery will spread, new generations of prey will appear and their populations will soar; then, it will be their season in the sun.