Cockroaches of the sea: Jellyfish threaten health of oceans

Published 9:01 am Monday, August 18, 2008

ORANGE BEACH, Ala. (AP) — Scientists in Orange Beach say there’s been a jump in jellyfish and other dangerous marine life on Alabama’s coastal beaches and they’re trying to find out why.

“It seems to have been an exceptional year for them,” Orange Beach Coastal Resources Director Phillip West said. “I don’t recall ever seeing as many and seeing them so early.” From Alaska to Africa, Australia to Alabama, scientists have noted with increasing frequency that jellyfish populations are on the rise.

Monty Graham, a Dauphin Island researcher who specializes in jellyfish, says there’s also a greater number of the types of jellies — more than 100 — swimming in local waters now than there were a decade ago.

Scientists say the reasons for the rise range from rising ocean temperatures, increased nutrients and phytoplankton growth, to overfishing of jellyfish predators, depleted oxygen levels and manmade breeding grounds like oil platforms, piers and reefs.

Some warn the apparent planetwide increase in jellyfish could spell looming sickness for the world’s oceans and say a sizzling welt is now low on the reasons to worry about jellyfish.

“People should be more concerned about the ecological effects than being stung on the beach,” Graham told the Press-Register in a Sunday story.

On a recent day, Graham and a pair of his fellow Sea Lab researchers, Randi Shiplett and Mairi Miller, went in search of a smack of jellies four miles wide that a colleague spotted from a plane the day before.

About two miles south of Perdido Pass, they found a swarm. Though not as dramatic as some recent blooms, there were hundreds, if not thousands, of nebulous moon jellies and fluttering, milky sea nettles drifting by the small boat.

On Friday, Graham said a Sea Lab trawler ran into masses of moon jellies south of Dauphin Island that were so thick researchers were unable to hoist the boat’s net back to its deck.

Shiplett said she suspects her thesis will show that jellyfish eat a lot of eggs of commercially important species such as snapper and red drum. Because of their versatility, ubiquity and ability to thrive in damaged environments, jellyfish are often pegged as the “cockroaches of the sea.”

In an article published this year, Graham ponders that nickname.

“There is no doubt that jellyfish will continue to increase and make the most of better conditions and new niches in the food chain,” he writes. “I also suspect cockroaches will be long gone when the last jellyfish swims in a lonely sea.”

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Information from: Press-Register, http://www.al.com/mobileregister