Gambusia holbrooki will, if need arises, switch food sources to survive. With an increase of competition, this species will switch from a diet rich in phytoplankton, algae, and detritus to one consisting of zooplankton, invertebrates, the larvae of many other fish and amphibian species, and plant-associated animals.
Gambusia holbrooki can adapt its diet based on environmental changes, particularly when facing increased competition. This species will shift from a phytoplankton, algae, and detritus-based diet to one that includes zooplankton, invertebrates, fish larvae, and plant-associated animals.