However, the fishing industry appears to defy all the Conventions, laws, and regulations, under which cetaceans are protected, and appears to be immune from prosecution.
Tens of thousands of cetaceans are dying in fishing nets each year. They become entangled in tangle nets, trammel nets, drift nets, and trawl nets, gill nets and long lines. The true extent of the bycatch problem is not known, as many fleets prohibit observers from boarding their vessels. However, studies that have been carried out show that the problem is of monumental proportions.
A study of the French albacore tuna drift net fishery 1992 - 1993 (when only 27% of the effort was observed) showed an annual bycatch of 415 common dolphins and 1170 striped dolphins. In 1995, a study of the UK tuna drift net fishery (when only 28% was observed) revealed that the annual bycatch of dolphins was TWICE that of the French.
These drift net fisheries were banned from January 1st 2002, except in the Baltic Sea, but the powerful tuna fishing lobby plans to seek a ruling from the European Court to maintain tuna drift net fishing.
Studies have estimated that the annual bycatch of harbour porpoises in the Celtic Sea hake gillnet fishery, is of the order of 2237 individuals, but this estimate does not include the bycatch from any UK boat under 15 metres in length, any Irish boat under 10 metres, any of the French boats, or any of the tangle net boats. Neither does it include a proportion of bycaught porpoises which disentangle from the net during hauling, that are already dead.
In 1998, when only 238 hauls of the English bottom set gillnet fishery in the Celtic Sea were observed, there was a bycatch of 16 harbour porpoises, 7 of which were caught in nets with pingers.
It is estimated that 7000 harbour porpoises are caught in Danish North Sea gillnet fisheries each year, and 1000 in the UK North Sea gillnet fisheries. In the Skagerrak it is estimated that 110 porpoises are caught in the Swedish cod gillnet fishery each year. Estimates suggest that 6.2% of the total population of harbour porpoises in the Celtic Sea is killed each year in fishing nets, and 4% of the total population of harbour porpoises in the North Sea. The International Whaling Commission has stated that a continual kill rate of only 1% of a cetacean population, will render it non-sustainable.
Many thousands of cetaceans are killed in trawl nets annually, including minke and pilot whales. The trawlers which cause the greatest problem are pelagic (mid-water) trawlers. Available information suggests that potentially high numbers of common, white-sided and striped dolphins are being killed in trawl fisheries in the Northeast Atlantic each year. Further estimates suggest that up to 50 dolphins may be taken in a single tow by Irish pelagic trawlers.
The most destructive of all pelagic trawlers, are the pair trawlers. The Scottish, English, French, Danish and Dutch pair trawlers tow nets of gigantic proportions. They are so large that 12 jumbo jets could easily fit inside one net. It is estimated that in a six-week period at the beginning of 2000, in excess of 2000 dolphins died in the nets of French and Scottish pair trawls alone.
In a recent study of the UK seabass pair trawler fishery, 20dolphins were taken in a single haul of a pair trawler.
During a study of the Irish tuna pair trawl fishery, 4 pairs of trawlers were monitored. In only 313 hauls, a total of 145 cetaceans were taken – 127 common dolphins, 8 striped dolphins, 2 Atlantic white-sided dolphins and 8 pilot whales. 30 cetaceans were taken in a single haul.
The result of this death and destruction is often seen on European beaches. A small proportion of bycaught cetaceans are found around the coasts of the UK, Eire, France, Belgium, Holland, Portugal, and Spain.
February 1989: 600 dolphins stranded in two days in Landes and Vendees, France.
January - April 1992: 118 dolphins (of which nearly half were positively identified ascommon dolphins) stranded in Devon and Cornwall - the vast majority showing signs of bycatch; in 1993, 20 common dolphins; 1996, 30 common dolphins. This pattern was mirrored on the coastlines of other European countries.
February - March 1997: in a three week period 629 dolphins stranded on the Southern Brittany and Biscay coasts.
February - March 2000: in excess of 600 dolphins stranded on the coasts of Cornwall, Devon and Brittany.