Dawn of the jellyfish

Each summer, jellyfish hit the headlines, prompting beach-goers to look twice before dipping their toes. This year, we are steeling ourselves for huge numbers of stingers hitting UK shores. Last year, we fought them on the beaches, and before that, villages up and down the Med were arming against an expected onslaught. Something about swarms of sea jellies lends itself to thrilling news stories. Even the collective terms for jellyfish – a ‘smack’ of jellyfish, or a ‘brood’ – suggest a battle in the making.

While everyone loves a good plague story, what makes the jellyfish so compelling? And aside for comic hyperbole, what is behind journalists’ description of the jellyfish peril in such apocalyptic terms?

Jellyfish don’t possess eyes, brains or specialised respiratory systems. While some use jet propulsion to power themselves forward, or hitch rides on seaweed, most rely on sea currents. When they sweep towards our beach resorts, the unthinking, but relentless, movement is rather like the slow, lumbering assault of our horror-movie friend, the zombie.

While the sluggishness of the zombie’s movements has been hotly debated of late, any horror aficionado will tell you that the tireless gait of the zombie represents the inevitability of death lumbering after us. You can outrun a zombie, but only for so long. Subconsciously, we see a similar menace in the broods of jellyfish moving towards our beaches: motiveless, unthinking, but as unstoppable as the tide itself.

Just as zombies uncomfortably remind us of our mortality, jellyfish invasions evoke the unconquerability of some of nature’s systems. But if we look deeper, there is nothing ugly or menacing about the jellyfish: as I hope to show in this blog, they have amazing qualities and are involved in some of the natural world’s most fascinating symbiotic relationships. Reader, embrace the wondrous jellyfish – but nonetheless, keep an eye out where you’re swimming this summer…