. >> bernardin workers at the harbor trade in black scabbard fish, which live in the deep waters of the atlantic. this load arrives by truck. it has come from scotland and has been on the road all night long. the trawlers, which belong to a company which is part of a french supermarket chain, have cleared their load in the far north. still, the fish is transported to france. >> the fish was sold en route. here is the buyer's ticket. >> the workers here will now prepare the boxes for delivery sometime between 3:00 and 4:00 in the morning. >> the issue is the method used to catch the deep-sea fish. kilometer long trawl nets are dragged along the seabed, leaving a trail of destruction in their wake. >> many creatures in these deep waters have a particularly long lifecycle and do not reproduce easily. it's an unknown world that contains vast numbers of species. like an underwater tropical rain forest. >> this underwater video shows the detrimental effects of trawling. the only economic advantage to this method is that it yields a large catch, but they cannot ask high prices for the deep-sea