Compass jellyfish

Compass jellyfish ©Alex Mustard/2020VISION

Compass Jellyfish

Scientific name: Chrysaora hysoscella
It's easy to see where the Compass Jellyfish got its name when you spot its brown markings - they look just like a compass!

Species information

Statistics

Bell: Up to 30cm across

Conservation status

Common

When to see

May to October

About

The Compass Jellyfish is a summer visitor to our shores, feeding on small fish, crustaceans and even other jellyfish. They get their name from the distinct brown pattern on their bell - a radial pattern that resembles a compass. They often wash ashore in summer months and it is this brown radial pattern that can be used to identify them on the beach. They give a nasty sting though - so look, but don't touch. If you are stung, jellyfish often leave the tentacle on your skin - it will continue to sting you even when not connected to the body! Scrape the area with a clean stick or remove the tentacle with tweezers if you have them to hand, then rinse the area with warm to hot water to reduce swelling.

How to identify

A translucent yellowish-white jellyfish with brown markings around the fringe and on the top of the bell. Those atop the bell resemble a compass, with V shapes radiating out from a central point. They have a bunch of frilled oral arms below the bell and long thin marginal tentacles around the fringe of the bell.
Don't get too close to those tentacles though, they give a nasty sting.

Distribution

Common off Southern and Western coasts of Britain in summer months.

Did you know?

Young fish can often be seen swimming around the Compass Jellyfish's tentacles, giving them protection from predators. We're not yet sure why they don't get stung and eaten by the jellyfish though!

How people can help

Report your Compass Jellyfish sightings to your local Wildlife Trust. The Wildlife Trusts are working with sea users, scientists, politicians and local people towards a vision of 'Living Seas', where marine wildlife thrives. Do your bit for our Living Seas by supporting your local Wildlife Trust.