Thursday, August 16, 2007

Spotted Australian Jellyfish return to Area Waters

Published by the Mobile Press Register

Spotted jelly invaders return

Thursday, August 16, 2007
By BEN RAINESStaff Reporter

The basketball-sized Australian spotted jellyfish that swarmed Mississippi Sound in 2000 have made "a vigorous reappearance" in area waters and have also been sighted along the Atlantic Coast as far north as the Carolinas.
Scientists do not believe the local population will be large enough to present any problems for shrimpers or commercial fishermen this year, as they did in 2000, when shrimping became impossible in places. But they said the East Coast sightings raise the possibility that the jellyfish could become established along both the Gulf and Atlantic coasts.
While the invasive spotted jellies (Phyllorhiza punctata) do not sting, other stinging species common in Alabama waters are especially thick this year due to the higher salinity levels resulting from drought conditions throughout the state, according to Dauphin Island Sea Lab scientist Monty Graham, one of a handful of jellyfish experts in the world.

Unless hurricanes or tropical storms visit the area, it is likely jellyfish numbers will remain uncomfortably high through October, Graham said.
When the spotted jellyfish was first seen in Mobile Bay in 2000, scientists believed that an aberration in the Gulf's loop current had moved tens of thousands of the animals from the Caribbean and deposited them along Alabama's coast.
Since then, genetic work performed at the Dauphin Island Sea Lab by Keith Bayha has shown that the animals along the Gulf coast were genetically different from those in the Caribbean, and scientists have discovered that the species is reproducing along the Louisiana coast, particularly near Port Fourchon. The animals in Alabama this year and those that showed up in 2000 appear to come from that Louisiana population.
Graham said the jellies that first turned up in July were about the size of a man's fist. They have been growing ever since, and ultimately may get up to about 25 pounds. He believes far fewer jellies were deposited here by the current this year compared to 2000, and said it was unlikely they would present a problem for shrimpers or be a threat to larval fish and shrimp populations.
In 2000, the animals were so numerous in Mississippi Sound that scientists worried they would cause lasting damage to area fish and shellfish populations. It is unclear if the jellies have started reproducing off Alabama's coast.
"If they are, it's a small population. I suspect they probably are here somewhere, but I think the core of the population is around Port Fouchon," Graham said, adding that the hundreds of rigs around the port, which is in the heart of the Gulf's oil field, provide the hard surfaces jellies require for spawning.
Beachgoers and boaters are encouraged to report their sightings of these exotic jellies to the Dauphin Island Sea Lab's jellyfish Web site,

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