Bass are apex predators in the water, but they are also preyed upon by all sorts of animals, including waterbirds, snakes, and mammals. Big bass will also eat smaller bass, which means that many of them don’t live very long. In an ideal setting, smallmouth and largemouth bass will have an average lifespan of 6 to 15 years. The oldest largemouth bass ever caught was around 19 years old, and the oldest smallmouth on record was closer to 20.