Western Australian Veterinary Emergency and Specialty (WAVES) head of emergency and critical care Katrin Swindells, who treated the dog which survived, said the clinic was still waiting on toxicology reports to confirm if it was 1080.
She warned dog owners to keep their pet on a leash and take precautions if they walked their dogs at the park.
‘There are a lot of environmental toxins in WA, including plants, to which dogs are sensitive,’ she said. ‘But if dog owners suspect their dog may have been poisoned, they should contact their vet.’
Get in front of tomorrow's news for FREE
Journalism for the curious Australian across politics, business, culture and opinion.
READ NOWSigns of 1080 poisoning include howling, severe agitation, running around wildly, seizures and fits.
If dogs display these symptoms they should be taken to the vet immediately.
On April 7, a staffy cross was rushed to WAVES after it started vomiting, falling over, having seizures and howling.
It died en route to treatment.
The owners had walked the dog at Rushton Park earlier that evening.
On April 20, the same dog owners walked their kelpie cross at Rushton Park.
In the early hours of the morning, it jumped up off the bed and started displaying the same symptoms as the staffy cross.
The owners rushed the dog to WAVES, where Dr Swindells and two other veterinarians were able to save it by pumping its stomach and giving it activated charcoal.
Dr Swindells said she had spoken to another dog owner who walked their golden retriever at Rushton Park on April 9.
It died that night after becoming agitated, howling and having seizures.
City of Armadale acting chief executive Tony Maxwell said rangers had carried out inspections, but had not yet identified anything that could be poison.
‘No baits have been found and we are not aware of poison being laid at Rushton Park for any reason,’ he said.
The City’s rangers have confirmed they had not dispensed the poison.