Because the giant water flea is protected from predators by its size and large spines, it may reduce the growth of larval sport fish, including bass and sunfish.

While some species of fish decline, other fish species may benefit from the presence of the giant water flea.

The giant water flea competes with native zooplankton for food and has replaced some species, especially in areas that are warm.

Replacement of native species can change the entire community of other zooplankton present.