Rock Bass are members of the sunfish family, and live in rocky areas in the shallows, hence their name. As adults, they live in groups, often with smallmouth bass and other small fish as well. They spawn in the spring, when water temperatures reach around 55 to 60 degrees Fahrenheit. The males dig nests in the shallows, just like other members of the sunfish family, and they guard the nest constantly. Spawning areas become very heavily used at some points, so the males can become quite aggressive during the spawning season as they attempt to guard their own nest and attract and hold females.
Once the eggs are layed, the males job is to fan and guard the eggs. When the eggs hatch, the male broods the young rock bass for a short time. Small Rock bass grow quickly, but are prey to northern pike, muskie, walleye, and other larger rock bass. On average, adults will weigh 4 to 8 ounces, and have a length of 8 inches, although some are known to grow up to 10 inches. Adults compete with small mouth bass for food, which is usually small fish, crayfish, aquatic insects, yellow perch, minnows, and sometimes their own young.
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