Investigation finds illegal net-setting caused death of Hector's dolphin

The investigation was launched after a member of the public found a dead Hector's dolphin on Blaketown beach in Greymouth in March.

A Ministry for Primary Industries and Department of Conservation investigation has found that illegal net-setting is to blame for the death of a Hector's dolphin on the West Coast earlier this year.

The investigation was launched after a member of the public found a dead dolphin on Blaketown beach in Greymouth in March.

MPI compliance investigations manager Gary Orr said the investigation covered interviews with commercial fishers, local service stations, net makers and sellers and local iwi.

"Our inquiries were very thorough. We made sure that no stone was unturned. After a nearly three month-long investigation, reviewing the pathology report and examining data and environmental considerations, we have concluded that this animal's death was very likely to have been the result of the dolphin becoming fatally entangled in an illegal recreational set-net.

"The type of deep and narrow lacerations on its body are consistent with monofilament net which is used by recreational fishers rather than trawl mesh which is used by commercial fishers.

"Additionally, only one commercial vessel set-nets close to the area and it had not been fishing there at the time the dolphin died. We are confident this is not linked to any commercial fishing activity."

Orr said the pathology report showed a knife was used to cut the dolphin's tail off after its death.

"There are anecdotal reports that suggest fishers in some countries open up the abdominal cavity of mammal bycatch in an attempt to make them sink when they return them overboard. This may well have been the case here. That particular action is also an offence, even after death.

"Unfortunately, despite the fact we spoke to a large number of people, we have not been able to identify the individual or individuals responsible for this.

"We will continue to receive any relevant information. Solving this case depends on people doing the right thing and coming forward with information.

"We are appealing to anyone who may have seen anything suspicious around the Taramakau River mouth from the evening of Friday 10 February to the morning of Saturday 11 February, to contact us. The area where the dolphin was found is subject to a total ban on set-netting. Any recreational set netting in this area is illegal."

Under the Marine Mammals Protection Act, anyone who kills or injures a marine mammal must report the event.

The penalties for a commercial fisher who fails to report a capture of this nature are a fine of up to $100,000 and, for a recreational fisher, a fine of up to $10,000.

MPI is continuing to investigate the death of a Hector's dolphin near Banks Peninsula in March.