Behavioral syndromes can reduce population density: behavior and demographic heterogeneity

Behavioral syndromes are widely recognized as important for ecology and evolution, but most predictions about ecological impacts are based on conceptual models and are therefore imprecise. Borrowing insights from the theory of demographic heterogeneity, we derived insights about the population-dynamic effects of behavioral syndromes. If some individuals are consistently more aggressive than others, not just in interspecific contests, but also in foraging, mating, and anti-predator behavior, then population dynamics could be affected by the resulting heterogeneity in demographic rates. We modeled a population with a boldness-aggressiveness syndrome (with the individual's trait constant throug