They are gelatinous, pulsating, tentacled, and sometimes deadly. And they seem to be appearing in ever-increasing swarms across the oceans of the world.
According to a recent report from the National Science Foundation, it's time for us to figure out exactly what might be going on with these slimy-bodied invertebrates:
In recent years, massive blooms of stinging jellyfish and jellyfish-like creatures have overrun some of the world’s most important fisheries and tourist destinations—even transforming large swaths of them into veritable jellytoriums. The result: injuries (sometimes serious) to water enthusiasts and even occasional deaths.
Jellyfish swarms have also damaged fisheries, fish farms, seabed mining operations, desalination plants and large ships. And proving that jellyfish can be political animals, knots of jellyfish have done the work of anti-nuclear activists: they have disabled nuclear power plants by clogging intake pipes.
In short, since the 1980s, worldwide jellyfish blooms have caused hundreds of millions—or perhaps even billions—of dollars in losses. Worldwide reports of massive jellyfish blooms are triggering speculation that jellyfish swarms are increasing because of human activities. But are they?
The report presents a swarm locations map, showing areas where scientists or journalists have identified sharp rises in the number of jellyfish present. That list includes Australia, the Mediterranean, Chesapeake Bay, the Gulf Coast, the Bering Sea, Hawaii, the Black Sea, the waters around Great Britain and Northern Ireland, and even the coast of Namibia. NSF claims that environmental stress is to blame for these swarms, so we can add "giant jelly armies" to the list of disasters caused by global climate change.
The important question is: How much of this happens to be our fault? In a chart of all possible stresses that might affect our gloopy sea neighbors, the report pinpoints these five: invasions of non-native jellyfish, pollution, climate change, over-harvesting of fish, and dams. Humans are to blame for at least four of these. Whoops.
To make up for the havoc we may have wreaked on the ecosystem of these jellies (and to avoid getting Irukandji syndrome from a venemous horde of Australian box jellyfish, say), humans must get a handle on the causes of and solutions to this abnormal swarm activity. This NSF report is a good start.
Special Report: Jellyfish Gone Wild [National Science Foundation]
Pacific sea nettle jellyfish image from Wikimedia Commons.