SCARED TO DEATH? THE EFFECTS OF INTIMIDATION AND CONSUMPTION IN PREDATOR–PREY INTERACTIONS

• DOI: 10.1890/04-0719
• Publication Date: 2007-06-04T19:33:59Z
• Authors: Evan L. Preisser; Daniel I. Bolnick; Michael F. Benard
• Keywords: Intraguild predation; Intimidation; Trophic cascade

Predation is a central feature of ecological communities. Most theoretical and empirical studies predation focus on the consequences predators consuming their prey. Predators reduce prey population densities through direct consumption (a density-mediated interaction, DMI), process that may indirectly affect prey's resources, competitors, other predators. However, can also density by stimulating costly defensive strategies. The costs these strategies include reduced energy income, energetic investment in structures, lower mating success, increased vulnerability to predators, or emigration. Theoretical confirm existence induced (trait-mediated interactions, TMIs); however, relative importance intimidation (TMI) (DMI) effects remains an open question. We conducted meta-analysis assessing magnitude both TMIs DMIs predator–prey interactions. On average, impact demographics was at least as strong (63% 51% size total predator effect, respectively). This contrast even more pronounced when we consider cascading resources: attenuated food chains, while remained strong, rising 85% effect. thus strongly influence resource if they consume few items. Finally, important aquatic than terrestrial ecosystems. Our results suggest intimidation, traditionally ignored ecology, actually be dominant facet trophic