Lowdown on jellyfish

Sarah Ward, Living Seas Officer

This June and July we’ve seen a bloom in jellyfish numbers along the Sussex coast. This often happens at this time of year, and comes as no surprise given the spell of warm, settled weather we’ve had. Jellyfish eat plankton – they will follow their source of food but are drifters so are not able to swim directionally. This is why they drift in on currents and can sometimes be found in large numbers when they’ve all drifted together, and may even get washed up on the beach.

On a recent Shoresearch survey in Bexhill-on-Sea, we saw large numbers of Blue Jellyfish (Cyanea lamarckii) and Moon Jellyfish (Aurelia aurita). They had all come in on the low tide and were mostly washing around in tide pools; there were a few that were beached, which we gently moved back to the water (ensuring not to touch them with bare hands!).

There are six species of jellyfish (and two jelly-like relatives) which can be seen on UK coasts. All these jellyfish are able to sting so it is best to be cautious. If you do get stung, the best thing to do is remove any stingers still attached (a credit card is good to use to scrape them off – avoid using your fingers as you’ll end up with stung fingers as well) and rinse with water. If you have vinegar to hand, this will help to neutralise the sting. For most people the pain is relatively milk (akin to a nettle sting for most UK species) and should subside within a few hours; over-the-counter painkillers or antihistamines can help. Medical advice should be sought if you have a severe reaction.

Remember that jellyfish can still sting when they’re dead, so it’s best not to touch if you see one washed up on the beach. Wearing an exposure suit (eg a wetsuit) in the sea will protect you from possible jellyfish stings while swimming.

Have you seen a jellyfish? Here’s our guide to UK jellyfish and other jelly-like creatures.