australian spotted jellyfish in Alameda, CA

These jellyfish invaded the lagoon system on Harbor Bay island in Alameda for about a week or two, then either all left the area, or died. There were literally hundreds of all sizes (at least 200 when i first saw them, and they just got lesser and lesser every day), ranging from maybe the size of an egg, to dinner plate size (the bell). (at least 200), and everyone in the town saw them. (they might have died due to the poor filtration of the Harbor Bay lagoons. It was during a heatwave when they showed up, and when they all vanished, the weather was very cold and rainy)

I was curious and sent my picture of the jellies to Wyatt Patry, Aquarist II at the monterey bay aquarium, and he told me that i was right, and these were indeed australian spotted jelly fish and i should post this here, because he doesn't think they have been found this far north.

They were not found in the entire lagoon system either, only in one little section near our Safeway.

The date of my sighting was around mid to late october. 10/9/10 is an estimate, but, im almost positive that was the day.