DOZENS of dead grackles found in the North End in August were poisoned.
A provincial spokeswoman said Thursday toxicology results found evidence of the chemical anticholinesterase, commonly used in materials for controlling rats and pigeons by affecting the nervous system.
The birds were found in early August outside the Ma Mawi Wi Chi Itata community centre on King Street, while about 20 more were found on the roof of the buildings, some dead and others twitching.
The province said there have been no other reports of unusual bird deaths.
While there are laws prohibiting the poisoning of domestic birds and some wild species, there is no legal protection for grackles.
The provincial spokeswoman said grackles are not considered migratory birds, and, as a result, are not protected under Manitoba's Wildlife Act.
The spokeswoman said the province could not determine if the poisoning was deliberate, adding the toxicology tests were conducted solely to determine the cause of death.
The province wanted to ensure the grackle deaths were not caused by a virus or disease that could spread to other bird species.