Swimming with Jellies

Andrew Wallace
24.05.19 01:08 PM Comment(s)

It's that time of year again....


The jellyfish are back like clockwork, putting in an appearance from early May and growing steadily in numbers, and size.


Recently at Freshwater East, for example, we have noticed increased numbers of barrel jellyfish and now moon jellyfish have also started to make an appearance.

Open water swimming pembrokeshire
A large barrel jellyfish at Freshwater East

Lot's of people get freaked out by these large animals, but in fact they do not sting once they have matured to this size and in fact only the very young, miniature sized barrel jellyfish will cause irritation.


Very much a seasonal arrival, these creatures will turn up as the sea starts warming and also in time for the arrival of blooms of algae, plus the arrival of hundreds of spider crabs which can be seen spawning (and occasionally eating jellyfish!) on the sea floor.

The big barrels tend to swim around 1-2m deep, so normally you can swim right over them, but sometimes they drift to the surface and if you;re not looking out for them you can swim right into them, we'd advise just being prepared and looking where you're going! If you see one, stop and look at it, learn how they move and get used to it - it will make it easier when you see them next time!

Andrew Wallace