Nylon barium sulphate gillnet reduces porpoise and seabird mortality

Metal oxide nets containing barium sulphate (that increased their acoustic reflectivity and probably also their stiffness) reduced the bycatch of harbor porpoise (Phocoena phocoena) in an eastern Canada demersal gillnet fishery. No difference in catch of commercial fish species, including cod, pollock, haddock, and spiny dogfish, was observed between the nylon and barium sulphate nets. Metal oxide nets reduced the bycatch of greater shearwater (Puffinus gravis) in an eastern Canada demersal gillnet fishery, probably by increasing the visibility of the blue-dyed nets to the birds.
Field Studies:

Location	Fishing gear	Reduction technique	Bycatch species	Effect on bycatch species	Catch	Effect on target catch	Type
Canada	Gillnets	Metal oxide/barium sulfate nets	Small Cetaceans (maximum length < 7.5 meters)	Reduced harbor porpoise bycatch	Multiple species	No difference in catch	In the wild
Canada	Gillnets	Metal oxide/barium sulfate nets	Seabirds	Reduced bycatch	Multiple species	Did not affect target catch	In the wild