M. dolomieu is found in clearer water than the largemouth, especially streams, rivers, and the rocky areas and stumps and also sandy bottoms of lakes and reservoirs. The smallmouth prefers cooler water temperatures than its cousin the largemouth bass, and may be found in both still and moving water. Because it is intolerant of pollution, the smallmouth bass is a good natural indicator of a healthy environment, though it can better adjust to changes in water condition than most trout species. Carnivorous, its diet comprises crayfish, insects, and smaller fish, the young also feeding on zooplankton.