sentences:  Around 1990, French bottom trawlers began to fish for Portuguese dogfish and leafscale gulper sharks ("Centrophorus squamosus") west of the British Isles for meat and livers; these two species are together referred to as "siki".The "siki" catch peaked at 3,284 tons in 1996 before declining to 1,939 tons in 1999.The French have since been joined by Norwegian, Irish, and Scottish longliners and trawlers, making the Portuguese dogfish a significant component of deepwater fisheries in the northwest Atlantic.