Smallmouth Bass are good indicators of methylmercury exposure to humans and wildlife because they are a common, popular sport fish and eat a variety of food during their lifetime. Juvenile Smallmouth Bass – smaller than 150mm in length - eat zooplankton, or microscopic animals. Early reproducing Smallmouth Bass – 150-250mm in length - eat mainly zooplankton and other invertebrates – such as bugs. Harvestable Smallmouth Bass – those larger than 250mm in length - eat mostly crayfish and fish.
Photo dedicated by Idaho Power Company to the Public Domain.