Ontario, Canada's Ministry of Natural Resources is doing lab tests to determine what killed the thousands of birds that now lay dead on a beach.
As they clean the dead bodies off the beach they're estimating that around 6,000 birds have died.
There have been similar situations where birds were eating botulism-laced fish and this was killing them. So that's what they're testing for first.
They say it's not a threat to people but that they should keep their pets in check.
This is the largest die-off officials have seen in years, covering an almost 2 mile stretch of beach.
[Image via WENN.]