Thursday, 28 August 2008
Last Tuesday's tide stranded jellyfish on the beach. A couple of dozen blue blubber (Catostylus mosaicus) were laid out along the southern side of the spit at Limeburner's Bay; a handful more on the northern side.
Like other rhizostome jellyfish, blue blubbers lack tentacles and a central mouth. Instead they possess lobed arms, each of which has a mouth at the tip. (Take that, 'Dr Who' scriptwriters!)
The blue blubber is the most abundant big jelly around Melbourne. It prefers sheltered water and estuaries and forms extensive swarms in Port Phillip Bay, where it is harvested under licence for export to China and Japan.
Currently the minimum catch required to maintain a licence is 150 tonnes. Given that the average weight of an adult blubber is a little over a kilo and that they are caught individually in dip nets, that's a shedload of work.