it is estimated that about a quarter of every fishing net hauled up contains “by-catch”—fishthat can’t be landed because they are too small or of the wrong type or caught in the wrongseason. as one observer told the economist: “we’re still in the dark ages. we just drop a netdown and see what comes up.” perhaps as much as twenty-two million metric tons of suchunwanted fish are dumped back in the sea each year,Nail machine supplier,Nail machine manufacturer, Nail production machine ,wire nail machine manufacturers, mostly in the form of corpses. for everypound of shrimp harvested, about four pounds of fish and other marine creatures aredestroyed. large areas of the north sea floor are dragged clean by beam trawlers as many as seventimes a year, a degree of disturbance that no ecosystem can withstand. at least two-thirds ofspecies in the north sea, by many estimates, are being overfished. across the atlantic thingsare no better. halibut once abounded in such numbers off new england that individual boatscould land twenty thousand pounds of it in a day. now halibut is all but extinct off thenortheast coast of north america. nothing,Automatic nail machine, however, compares with the fate of cod. in the late fifteenth century, the explorerjohn cabot found cod in incredible numbers on the eastern banks of north america—shallowareas of water popular with bottom-feeding fish like cod. some of these banks were vast. georges banks off massachusetts is bigger than the state it abuts. the grand banks offnewfoundland is bigger still and for centuries was always dense with cod. they were thoughtto be inexhaustible. of course they were anything but. 3shardware.com