Foods That Lagoon Fish Eat

The coastal lagoons of the world are important ecosystems bridging inland water systems with the ocean. They are home to a diverse range of fish, which both feed on, and serve as prey for, other creatures living in or near lagoons. The diets and living habits of lagoon fish around the world are as diverse as the range of lagoon fish itself.

  1. Anatomy and Lagoon Fish Diet

    • How lagoon fish are built directly reflects their diet. Fish that regularly eat plankton have deep gill rakers for drawing plankton-filled water into their bodies, while streamlined, fast-moving fish are built to pursue fast-moving prey. However, even slower-moving fish can be successful carnivores; those with prominently protruding mouths, for instance, can catch small fish and other creatures as they pass without the need for a high-speed chase.

    Lagoon Fish Habitat and Diet

    • Lagoons are complex environments and include a diverse range of smaller ecosystems, each of which can be home to a different range of fish and other aquatic creatures Fish that favor different environments within a lagoon will vary in their dietary choices as well. For instance, a 2005 study by Michel Kulbicki et al. showed that pelagic fish in New Caledonia -- those who spend most of their time in the open ocean or the near-shore areas of lagoons -- tend to have less variety in their diets than other lagoon fish, since these areas are disfavored by many species due to their lack of sheltered areas. The same study showed that fish that favor reefs and sandy bottoms in lagoons, on the other hand, are likely to favor crustaceans.

    Traveling Patterns and Lagoon Fish Diet

    • The dietary habits of lagoon fish are also correlated with how far they travel. Michel Kulbicki et al.'s 2005 study of New Caledonia lagoon fish showed that the greater the traveling range of a fish species, the fewer free-swimming species tended to appear in its diet. The same study showed that crustaceans were a major part of the diets of fish with small to medium home ranges, while mollusks played a bigger dietary role for fish with medium to large home ranges.

    School Size and Lagoon Fish Diet

    • School size influences both dietary choices and variety for lagoon fish. Fish that travel in large schools tend to feed on a smaller variety of prey than those traveling in smaller schools, but solitary fish likewise tend to feed on a small variety of prey. Fish that travel in small or medium-size schools generally consume fewer free-swimming species than other species, and fish that occur in small schools tend to favor worms in their diets more than other fish.