Mysterious Jellyfish Swarms Seen in Europe, U.S.

Kimberly Johnson
for National Geographic News
August 11, 2008

The recent dramatic increases in jellyfish swarms along Atlantic and Mediterranean coasts highlight the need for more research into the life cycles of these stinging invertebrates, experts say.

Jellyfish are found along most coasts worldwide. The animals reproduce quickly, though populations typically recede during fall and winter months.

Recent news reports point to sharp increases in jellyfish blooms along New Jersey's Atlantic Coast and in the Mediterranean Sea.

(Read: "Jellyfish Invasion Puts Sting on Europe Beaches" [August 18, 2006].)

The phenomenon points to just how little is known about jellyfish, scientists say.

"Data do not exist to say if it's a long-term trend," said Monty Graham, a marine biologist at Alabama's Dauphin Island Sea Lab.

Empirical evidence is scattered and tricky to interpret, Graham wrote in a recent commentary in the journal Marine Scientist.

"Yet there is enough cumulative evidence to suggest real long-term increases in jellyfish have occurred in a number of ecosystems."

Making Headlines

A lack of hard data can skew the impact of seasonal blooms, experts warn.

While recent local news reports say that jellyfish are pushing their way inland into New Jersey bays and rivers, one expert said it's not a pronounced problem.

"We as an agency don't have any ongoing studies or data to support that there is an increase in the jellyfish population," said Elaine Makatura, spokesperson for the New Jersey Department of Environmental Protection.

Continued on Next Page >>




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