The Stanley Park Ecology Society is investigating after a large number of dead fish were found floating in Lost Lagoon.
Dozens of fish carcasses have been spotted while numerous other fish appear to be moving sluggishly.
The fish are believed to be common carp, a species that was introduced to the lagoon, located in Stanley Park.
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The water quality in the lagoon is being tested but it’s thought the die-off is probably a result of the weekend’s heavy rainfall, just when the water in the lagoon is turning over — a natural process that happens every fall.
The Vancouver Park Board said it is investigating, but there does not appear to be a risk to public safety.