Abstract: Shellfish harvesting devices including a frame to move over the submarine surface of a shellfish growing substrate and a plurality of tines extending down from it for penetration into the substrate, are improved by addition of a vibrator to impart a vibratory motion to the tines, but not appreciably vibrate other parts of the frame, e.g., runners. The harvesting of clams or like bivalves with the tines vibrating while being pulled through the substrate mitigates environmental damage to the shellfish growing area and reduces the energy required to pull the devices forward on the substrate.

Abstract: Apparatus for the cultchless cultivation of marine bivalve mollusks, e.g., oysters and clams, has a plurality of quadilrateral compartments connected together by a pair of longitudinal cords in the form of a continuous belt. In use of the apparatus, spat is placed in the culture chambers of the belt which then is immersed in an aquaculture plot and the spat is allowed to grow in such chambers. Later, portions of the belt are lifted out of the water while allowing the remainder of the belt to remain immersed and compartments in the withdrawn portion of the belt are cleaned and/or opened to process mollusks contained therein.