Sediments may cover submerged aquatic vegetation, killing the plants and reducing food needed by fish and other animals. Dead organic material can attract bacteria and can cause algae blooms, which consume oxygen in the water. Organisms including large fish die when oxygen levels fall too far. Fine particles that don't settle out can get stuck in the ventricles of fish. This can also lead to fish kills. Debris in the water can block sunlight, starving plants or causing algae blooms and lowering oxygen in the water.