Population Regulation of Cyclic Mammals: The Social Fence Hypothesis

An alternative population regulation mechanism is hypothesized which integrates population regulation and social behavior. When neighboring densities are low, spacing behavior regulates a central population through emigration. As neighboring densities increase, the effectiveness of spacing behavior to regulate central population densities is impaired. When the neighboring areas reach a sufficiently high density, the neighboring groups socially the central population by inhibiting further emigration. Once emigration is blocked, population regulation is achieved through resource exhaustion. The social fence hypothesis proposes that the effectiveness of spacing behavior to regulate population densities decreases as the social impermeability of neighboring groups increases. The evolution, operation, and predictions of this hypothesis are discussed.