An excavating vessel, also known as a dredger, is a type of ship used to excavate and remove material from the bottom of a body of water. It is typically used for digging out sand, mud, and gravel from the seabed or riverbeds. The dredger is equipped with a large suction pipe that sucks up the material and pumps it onto the deck of the vessel. The material is then sorted and transported to its destination.