Bycatch is also high from hook and line. Juvenile groupers tossed back into the sea don't necessarily survive, because pressure changes cause injury when they are hauled up from deep water. These species are mainly caught off Newfoundland, New England, and Europe. After several decades of overfishing and mismanagement, their collapse probably ranks as the world's greatest fishery-management disaster. Overfished and depleted, to the point of disrupting fishing communities in New England and Canada.
Mortality rates are high in many areas, such as the Gulf of Maine.
In large areas that have recently been closed to fishing, depleted populations are slowly increasing. The bottom-trawl nets used for these species sometimes entail the highest rates of bycatch of any fishery, except shrimping. The nets also scour the seabed, which degrades the habitat, lowering the potential for recovery in vast areas. Some scallops are farmed. Atlantic sea scallops are overfished and depleted.