Behavioral and physiological consequences of nest predation pressure for larval fish

Localized antipredator behaviors have been observed in a wide variety of taxa. Recent work has also shown that animals that provide parental care adjust their behavior when faced with variation in offspring predation pressure. This variation in offspring predation pressure may also influence the antipredator behavior of offspring if improved antipredator behaviors can increase their probability of survival. We tested if a natural gradient in nest predation pressure influenced antipredator behaviors of larval teleost fish (smallmouth bass, Micropterus dolomieu). We examined the predator avoidance of wild larvae from 6 populations that differed in nest predation pressure, and we also compared the recovery from a simulated predator attack of 2 populations at the opposite extremes of predation pressure. We found that larvae differed in their ability to avoid the nest predator, but larvae from lakes of low predation pressure responded similarly to larvae from lakes of high predation pressure. Generally, older offspring were not significantly better at avoiding predators relative to younger offspring, but we found a weak and significant positive correlation between the size of young offspring and their predator avoidance behavior. The recovery from a simulated predation event varied relative to predation pressure. Larvae from the site of high nest predation pressure exhibited reduced rates of maximal oxygen consumption and recovered faster than larvae from the low predation pressure site. Thus, variation in nest predation pressure had little influence on the antipredator behavior of offspring, which are provided with parental care but may have important metabolic consequences. Copyright 2011, Oxford University Press.