Complex sentence: By day, crappie tend to be less active and to concentrate around weed beds or submerged objects, such as logs and boulders; they feed especially at dawn and dusk, moving then into open water or approaching the shore.
Split into simpler sentences: By day, crappie tend to be less active and will concentrate around weed beds or submerged objects, such as logs and boulders. They feed during dawn and dusk, by moving into open water or approaching the shore.