Scaredy Fish — Eat or Hide

Project Title: Predator-prey interactions in mangrove and coral reef food-webs

Overview

The goal of this work is to explore food web dynamics, such as predator-prey interactions, in mangrove and coral reef systems. Predators can impact the distribution and abundance of their prey most obviously by killing and consuming them. However, predators can also impact their prey through “risk effects” (i.e. freighting their prey). By shifting their feeding areas or changing their feeding behaviors to avoid predators in response to risk effects, prey can subsequently impact the behaviors and abundance of other organisms, which can result in trophic cascades. Understanding these food-web relationships are important for developing models to help predict how human influences or changes in environmental conditions may impact ecosystem dynamics. This is particularly important given that mangrove and coral reef are among the most biologically rich, yet most threatened ecosystems in the world. Major impacts include overfishing, pollution, habitat destruction and climate change.

Some of the major questions we are currently investigating include:

  1. Does the diet and feeding intensity of mangrove and reef fishes differ seasonally?
  2. How are fish diets and foraging behavior influenced by food availability?
  3. Do mangrove fishes exhibit individual specialization in diet?
  4. How does predation risk on fishes differ spatially with proximity to mangroves and reefs?
  5. Does predation pressure on fishes differ between night and day in mangroves and reefs?
  6. Do mangrove and reef fishes exhibit food risk tradeoffs? If so, what behaviors do they use to avoid being attacked by predators?

SRC – In Focus

a tradeoff often exists between foraging opportunities and the risk

Understanding predator-prey relationships is important for developing ecosystem models which can be used by wildlife managers to help predict how human disturbances or changes in the environmental may impact ecosystem dynamics.