Contributing Monkie Sarah Backhouse
Published on January 16, 2008
Jellyfish are aquatic invertebrates and they’re found in every ocean in the world. With their gelatinous consistency, tentacles and — in the case of some species (like the box jellyfish) — a nasty sting, they probably don’t rank highly on most people’s list of favorite marine species. (Unless, of course, you live in China where they’re considered a delicacy.)
But love or loathe them, one thing is clear — there will be more of them. And soon.
As global warming heats our oceans, the incidence of jellyfish swarms will increase — so concludes the scientific research center CSIRO in a report to the Australian government’s Greenhouse Office. Blooms of jellyfish have already been reported around the world: in Japan, jellyfish “weighing as much as a sumo wrestler” have been clogging fishing nets, even shutting down nuclear power plants after one blocked a filter, according to Australia’s ABC News. They’re also affecting swimming beaches from Spain to Australia and have been reported in the North Atlantic, the Adriatic and the Gulf of Mexico.
Are these isolated findings? Not according to a study from the University of Western Washington. Researcher Jenny Purcell found that “warmer temperatures were related to larger population sizes for eleven species of jellyfish”.
Another study from the University of Washington sights over-fishing as a contributing factor to increased jellyfish blooms. The Black Sea proves an interesting example of this. Once an area teaming with fish, sustained over-fishing during a 40-year period saw the disappearance of mackeral and blue fin tuna, followed by anchovy and sprat. This resulted in jellyfish having virtually no competition for plankton, which created a population explosion.
It’s no surprise that a variety of human factors — including climate change, over-fishing and pollution — are changing the delicate eco-system in which we live. But the thought of us inspiring (or allowing) jellyfish to get fatter and reproduce more than space allows is too much for this human to bear.