Cetacean Bycatch Fact Sheet p1 of 2

CETACEAN DEATHS.

Harbour Porpoises.

Studies have estimated that the annual bycatch of harbour porpoises in the Celtic Sea hake gillnet fishery, is of the order of 2237 individuals.

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.

In total 6.2% of the total population of harbour porpoises in the Celtic Sea is killed each year in fishing nets.

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. This amounts to 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 should be cause for concern and investigation should take place as a matter of priority (IWC 1995).

In the Skagerrak it is estimated that 110 porpoises are caught in the Swedish cod gillnet fishery each year.

In addition countless porpoises die due to entanglement in gillnets in other sea areas other than those mentioned.

Many scientists are of the opinion that many also die in the nets of purse seiners and pelagic trawlers.

January – February 2002: There was an alarming increase in the number of porpoises stranding on the beaches of Southern England, many of which had no head or tail flukes. The vast majority showed signs of entanglement in nets.

Dolphins.

Studies have estimated that the annual bycatch of common dolphins in the Celtic Sea hake gillnet fishery is of the order of 200.

There are no estimates available for Danish North Sea gillnet and UK North Sea gillnet fisheries, but scientists suggest that the number must be in the hundreds.

Available scientific papers suggest that potentially high numbers of common, white-sided, striped and bottlenose dolphins are being killed in trawl fisheries each year, in the northwest and the northeast Atlantic, the Western Approaches, the English Channel, in Swedish, Danish and German waters and in the waters off northwest Ireland.
The highest dolphin mortalities are due to entanglement in the nets of pair trawlers.

Morizur et al (1997) suggested that up to 50 dolphins may be taken in a single haul of a pelagic trawl.

In a recent study of the UK seabass pair trawler fishery, 20 dolphins 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.

It is estimated that during the months January – March of this year, 4 000 – 10 000 dolphins died due to entanglement in the nets of pair trawlers fishing in the English Channel / Western Approaches.
The countries using this method of fishing in the Western Approaches are Scotland, England, Ireland, France, Denmark, and the Netherlands.

The following strandings figures further demonstrate the problem of cetacean bycatch in European waters

In February 1989: 600 dolphins stranded in two days in Landes and Vendee, on the French Atlantic coast.
Many of the bodies showed signs of incidental capture in fishing nets.

January - April 1992: 118 dolphins, mostly common dolphins, stranded in Devon and Cornwall - the vast majority showing signs of bycatch.
In 1993, 20 common dolphins stranded in Devon and Cornwall.
In 1996, 30 common dolphins stranded in the same two counties. This pattern was mirrored on the coastlines of other European countries.

Pelagic trawling for mackerel and pilchard was identified as the most likely cause of the mass mortality of common dolphins in Devon and Cornwall 1992/1993.
The same fisheries were thought to be responsible for similar strandings of common and white-sided dolphins off the south and west coasts of Ireland.

Pelagic trawling for herring was thought to be responsible for harbour porpoise strandings off the southern Irish coast.

February - March 1997: in a three week period 629 dolphins stranded on the Southern Brittany and Biscay coasts.
Many of the bodies showed signs of incidental capture in trawl nets.

February - March 2000: in excess of 600 dolphins stranded on the coasts of Cornwall, Devon and Brittany. Many of the bodies showed signs of incidental capture.

During the same period, French and UK pair trawlers, were fishing for sea bass in the Western Approaches.

Prior to 2000, 2-3 cetaceans stranded on the beaches of Jersey and Guernsey.

In 2000, 12 cetaceans, principally common dolphins, stranded on the beaches of Jersey.
In 2000, 24 dolphins stranded on the beaches of Guernsey.
In 2001, similar numbers stranded on the beaches of Jersey and Guernsey.

January – March 2001: Government figures show there was a 66% increase in the number of common dolphins, which stranded on the beaches of Cornwall. 94.44% of those post – mortemed were found to have died as a result of bycatch.