An additional factor contributing to the status of the Devils River minnow is the introduction of foreign species. Some introduced tropical and game species now compete with the Devils River minnow for food and spatial resources. Several nonnative species of catfish, cichlids, and bass have begun to reduce the minnow species’ numbers by feeding on both the minnows themselves and their main diet of algae and microorganisms. Loricariid catfish in particular have established large populations in the Texan habitats of the Devils River Minnow and are steadily consuming most of the available food. Largemouth bass also prey on the species’ juveniles during winter months, therefore reducing the amount of reproductively mature individuals. With the number of breeding individuals dwindling, the population is unable to replenish every season, leading to an even more rapid decline. The abundance of the Devils River minnow tends to fluctuate in accordance with the populations of their competitive and predator species
