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BRISBANE - More than two dozen penguins have died at the Sea World theme park on the Gold Coast.
The penguins became ill on Thursday last week and, by the weekend, 25 of the 37 sick birds were dead, Sea World said in a statement.
The surviving penguins had been isolated while vets continued their investigations into the cause of the deaths.
But Department of Primary Industries general manager of animal biosecurity Ron Glanville said today disease had been ruled out.
"We don't believe there is any other threat to animals at Sea World at this stage," he told ABC Radio.
"It does not appear to be an infectious cause that is going on so we don't believe there is a problem in terms of a threat to other animals or the public."
Sea World's manager of marine sciences Steve McCourt told the Courier-Mail newspaper today he suspected the deaths were caused by a load of contaminated gravel placed in the bird's enclosure as part of three-monthly maintenance.
"All the staff here are absolutely devastated about this," Mr McCourt said.
"We think there is some sort of toxin in the gravel."
Sea World first took samples to a private laboratory and then called in personnel from the newly-established Biosecurity Queensland, which worked on Monday night to clear up fears of bird flu.
Biosecurity Queensland principal veterinary officer Ian Douglas said tests for bird flu were negative.
"It's a bit too early to speculate what's happened," he said.
"But in the veterinary world, it's not unusual to get a large number of animals affected at the one time.
"If one is exposed to a toxin then often they all are and you get large crashes."
Dr Douglas said he had never seen a similar occurrence with penguins.
- AAP
