Dog deaths and vomiting after beach walks

One of the dogs died on the North Shore's Cheltenham Beach. Photo / Herald on Sunday

A Devonport vet has seen four cases of dogs with severe vomiting after being walked on a local beach.

A dog died after visiting a Browns Bay beach last month, and a second death was reported on Cheltenham Beach in Devonport yesterday.

Devonport vet Neil Waddell said he has seen dogs with severe vomiting and abdominal pain after they had been walked on Narrow Neck Beach over the last two days.

Dr Waddell said the dogs tend to get a bit depressed and don't want to eat anything which is out of character.

Just what killed two dogs and made others sick is so far a mystery, despite tests being carried out in laboratories.

North Shore District Council environmental health team leader Duffy Visser said "A woman rang to say she saw her dog eating or licking something in the distance, and shortly afterwards it threw up and then died".

She said a pathologist's report on the dog was not yet available.

"We were lucky enough to get some of his vomit that was still on the beach," Ms Visser said.

Two other dogs were reported to have been ill but have not died.

Ms Visser said it could be a poisonous algae but tests had been inconclusive as to the cause of the deaths and illnesses, Ms Visser said.

"We're advising people to keep their dogs away from the beaches for now until we find out what it is," she said.

Ms Visser said the council rushed to put signs up on the beaches yesterday and will put more up today.

Further north in the Rodney District, dead fish have been washing up on beaches and dead penguins have been found in the dunes around Mangawhai and Te Arai Pt.

Rodney District Council spokesman Mike Isle said the council's job was one of "picking up the corpses" rather than finding out what was killing the marine life.

He said it is normal for penguins to be found washed up dead in the winter but some of the birds had been found in the dunes, indicating that they were alive when they came ashore.

Mr Isle said dead fish have also washed up on beaches around the Whangaparaoa Peninsula. He said most of the fish have been pilchards but the odd john dory had also been found.

Mr Isle said so far there are no reports of dogs being ill or dying in Rodney.

The Department of Conservation has been dropping a blood thinner poison on Rangitoto and Motutapu islands to kill rats and mice but says the deaths of the dogs and marine life and the poison drop is "highly unlikely" to be linked.

Sheep, cattle and horses have been removed and the islands will be closed to visitors for a week after each drop that will continue for the next three months.

DoC spokesman Bill Trusewich said large numbers of pilchards dying every five or so years is not out of the ordinary but there is "definitely something going on".

"All of these things could be occurring in parallel and it doesn't necessarily mean that they are related to each other," Mr Trusewich said.

He said there had been similar deaths in Wellington sometime ago they were a result of an algae bloom.

Mr Trusewich said the toxin that DoC is using on the islands is Brodifacoum, an anti-coagulant.

He said the symptoms that the dogs have shown is inconsistent with the poison and dogs would need a big dose to die.

- NZ HERALD STAFF & NZPA