FYI:
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Swan River Trust - Warning: Jellyfish in Freshwater Bay
The Swan River Trust has issued a new alert after a number of unusual jellyfish were spotted at the Claremont Jetty in Freshwater Bay.
The Trust alerted the public in July 2010 after a number of jellyfish, recently identified as Carybdea xaymacana, were seen in the Swan River between Preston Point and Fremantle Harbour.
On 20 August 2010, a member of the public reported a smaller number of these jellyfish in Freshwater Bay.
While this species is a common ‘stinger’ in waters off Perth and between Geraldton and Busselton, it is unusual for it to extend so far upstream into the Swan River.
The Trust reminds the public to avoid contact with these jellyfish as they can cause a nasty sting.
The Department of Health recommends that stings should be treated immediately by flushing with undiluted household vinegar. Do not rub the sting. Stings cause moderate pain for up to two hours, and some swelling and redness. Medical assistance should be sought if shortness of breath is experienced or symptoms persist or worsen. If in doubt seek medical advice.
The Trust encourages the community to report any river issues to the Trust on (08) 9278 0900 during office hours or 0419 192 845 after hours. An image of the jellyfish is available at www.swanrivertrust.wa.gov.au.
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Hopefully they don't hang around for summer, but seeing how other jellies flourish in the Swan who knows?
I wonder if its a coincidence that the swan/avon has had pretty much the lowest flows on record this year. No cold fronts = no rain to flush out the river. Its all tidal movement.
We skipped winter this year. 
Yeah I noticed its heaps saltier than last year. The normal white jellies are coming back too
