Digging and harvesting device for seafood farm

An excavating and harvesting device for a seafood farm comprises a pontoon, an excavator is fixed to the pontoon, and pontoon positioning mechanisms are symmetrically arranged on the two sides of the pontoon and used for anchoring the pontoon during operation; a screening bucket is mounted at the front end of the excavator; the pontoon positioning mechanism comprises a mounting frame, a hydraulic cylinder is hinged to the mounting frame, two long connecting rods are symmetrically hinged to the outer side wall of the pontoon, the opposite ends of the two long connecting rods are hinged to the lower end of a piston rod of the hydraulic cylinder through short connecting rods respectively, and anchor plates are fixed to the outer ends of the long connecting rods respectively; the screening excavator bucket comprises an excavator bucket frame, the excavator bucket frame is of a hollow structure, a supporting plate is connected between the tops of side plates on the two sides of the excavator bucket frame, two rota