EVIDENCE FOR A DOME-SHAPED RELATIONSHIP BETWEEN TURBULENCE AND LARVAL FISH INGESTION RATES

Recent theoretical work suggests that small-scale turbulence enhances encounter rates between larval fish and their prey. This finding has been extended to suggest that feeding rates will increase in turbulent environments. However, this extrapolation assumes that turbulence has no detrimental effects on post-encounter behaviors (e.g. pursuit success). We develop an analytical model to estimate the probability that larval fish feeding in turbulent environments successfully pursue encountered prey. We show that the overall probability of feeding is a dome-shaped function of turbulent velocity and that the height and location of the maxima depend on turbulence level and the behavioral characteristics of predator and prey. Highly turbulent conditions (e.g. storms) will reduce feeding rates below those which occur during calmer conditions and will affect the type of prey captured and ingested.