North Shore environmental staff say they haven't had any reports of people suffering from a mystery beach ailment which has seen two dogs die.
One dog died after visiting a Browns Bay beach last month, and a second death was reported this week on Cheltenham Beach, Devonport.
A number of other dogs were reported to have become ill without dying on North Shore beaches.
Dog owner Jenni McManus says her dog Rocky became violently ill after a run on Narrowneck Beach in Devonport.
"By the time we got in the gate he was actually vomiting a white foaming stuff and it was just constant," she says.
She rushed rocky to the vet just in time.
Residents have been advised not to walk their dogs on the beach but North Shore District Council environmental health team leader Duffy Visser said she hadn't heard of people being affected.
"That is a big concern, but there are no reports of people suffering yet," she told NZPA.
"Usually if there is a toxic algae it is more along the lines of an allergic reaction but we haven't heard of anything yet."
"Fortunately there are not many people using the beach at the moment but there are some so, we are keeping an eye on that."
The council is running a series of tests on the shoreline and the bodies of a number of penguins, seagulls and fish have also been washed up.
Some test results from this week's death have been sent away but results are not likely to be available until Friday.
Authorities want people to let their local vets know, if they have had any issues with their dogs in the affected areas.
Also, if you are aware of any fish deaths, please
contact the Emergency Pest and Disease hotline on 0800 809966. They