Final answer:
Snowshoe hare populations cycle with periods of increase and decrease, influenced by lynx predation (predation hypothesis) and internal density-dependent factors such as crowding and stress (density-dependent hypothesis).
Step-by-step explanation:
The population cycles of snowshoe hares are characterized by periodic fluctuations in numbers approximately every ten years, influenced by predator-prey dynamics with the lynx. Two main hypotheses explain these patterns: the predation hypothesis and the plant-based, density-dependent hypothesis.
The predation hypothesis suggests that when hare numbers grow, lynx numbers also increase due to abundant food. However, this eventually leads to a drop in hare numbers as lynx predation intensifies. Consequently, the lynx population then declines due to the reduced hare population, their primary food source.
The density-dependent hypothesis focuses on the internal factors within the hare population, such as crowding and stress-induced lower fecundity. This hypothesis posits that the snowshoe hare numbers rise and fall due to intrinsic factors regardless of lynx predation, which in turn affects the lynx population as a secondary effect.