The Western Australian Seabird Rescue group believe a possible botulism outbreak is the cause of a number of reported duck deaths at a lake in Meadow Springs.
The disease, which is produced by a bacteria that is found in rotting food, carcasses and soil, leads to paralysis and is one of the most common causes of death in birds.
The lake is in a park bordered by Glenelg Way, Pebble Beach Boulevard and Grandmere Parade.
Western Australian Seabird Rescue said botulism outbreaks happen every year following "the first autumn rains" and occurs when the birds eat food or drink water that contains the toxin.
"The heavy rains have re-flooded many wetlands and we are about to have a few warm days so botulism outbreaks could occur anywhere," their Facebook post read.
The group has asked residents who see any sick or dead birds to call them on 6102 8464.
"It's critical to remove the dead birds from the water so other birds don't feed on their carcasses and become affected too," the Facebook post read.
"If you walk your dogs around this park, please keep your dogs ON LEAD (so they don't pick up an infected carcass).
"Please DO NOT throw bread or other food into the water as this will affect the nutrient quality and exacerbate the issue."
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