Pots and Traps     Hook and Line     Traweling/Dragging      Purse Seining      Longlining      Gill Nets      Harpooning      Dredging   Dredging Is a form of bottom trawling that specifically targets shellfish that live on the seafloor.  The dredging rig is comprised of a heavy steal frame enclosed by heavy netting.  Often the leading edge of the dredge has steel teeth or other devices attached to stir up shellfish, which burrow into the mud of the seafloor.  Water sand and mud pass through the mess but the nets are made mainly of metal to enable to withstand being drug across the seafloor. Disadvantages -Dredges cause an extraordinary amount of damage to the seafloor environment.