A Moreton Bay Regional Council spokesperson said council had received a report of approximately 40-60 dead mullet on the beach at Welsby Parade, Bongaree.
"Council officers have worked quickly to remove all the dead fish, and investigate the incident," the spokesperson said.
"There does not appear to be any signs of pollution which could have impacted the fish, and other fish species do not seem to be impacted.
"Mullet are in abundance this time of year, meaning increased commercial and recreational fishing for the species.
"This incident could have been a result of fishing activity.
"Council will continue to monitor the area."
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