A BLUE-GREEN algae which can cause skin, eye and respiratory irritations has been detected on Coochiemudlo Island's Main and Norfolk beaches.
Redland City Council has put up signs warning of the presence of the naturally occurring algae lyngbya majuscule.
A council spokesperson said the presence of lyngbya was not uncommon in waters around the Redlands and Moreton Bay.
"... All Coochiemudlo Island beaches and waterways remain open for recreational use," the spokesperson said.
"The signs are precautionary only to inform people of the presence of the material, which often presents as mats floating on the surface of water or as washed-up clumps of on the beach.
"Swimming and wading is not recommended where algae is present."
Council would monitor the beaches on Coochie and at Victoria Point.
Read more about lyngbya at ehp.qld.gov.au/coastal/ecology/lyngbya-updates.
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