Ecology of fear.

The 'ecology of fear' refers to the total impact of predators on prey populations and communities. The traditional view in ecology is that predators directly kill prey, thereby reducing prey survival and prey numbers - and that this is the limit of their ecological role. The ecology of fear posits that the behavioural, physiological and neurobiological costs of avoiding predation ('fear' for short) may additionally reduce prey fecundity and survival, and the total reduction in prey numbers resulting from exposure to predators may thus far exceed that due to direct killing alone. If this is the case, then failing to consider fear as a factor risks profoundly underestimating the ecological role predators play.