I saw a picture of a very impressive , if rather scary looking jelly fish posted on Facebook by a friend of mine on Monday. She was at our local beach and I saw a few comments from other people who had also seen quite a number of these scary looking creatures at other beaches in South Wales.
Well I looked it up on the marvellous internet and it turns out that this ‘invasion’ was predicted as far back as May this year and there have been reported sightings(here, here, here and here) all summer of these ‘monsters’, more commonly known as barrel, dustbin-lid or frilly mouthed jellyfish. It’s been happening in America too as recently as today, with other types of jellyfish washing up on the beaches as this article explains.
The Marine Conservation Society considers jellyfish populations as important indicators of the state of our seas and ask the public to report sightings in order to gather information needed to understand more. Results from jellyfish surveys so far indicate that numbers are increasing around the world, more than likely linked to the following factors.
1) Climate change: We had a relatively mild winter. Jellyfish sink to depths in winter and wait for warmer weather before coming back up to the surface. Most jellyfish only live for one year but these ones can survive multiple seasons so if the winter is mild, there’s more chance of them surviving.
2) Over fishing: Jellyfish babies develop from tiny ‘polyps’ which attach to the sea bed. They grow and bud off into thousands of tiny larvae. It used to be that not many of these would survive being eaten by fish however this trend is changing due to over-fishing. Also threatened by over-fishing is the highly endangered leatherback turtle.
3) Plastic pollution problem: Leatherbacks eat twice their weight each day and their staple diet is jellyfish. Unfortunately, they can’t distinguish between jellyfish and clear plastic rubbish such as sandwich bags and there have been studies done where nearly half of all leatherbacks examined had plastic or cellophane in their stomachs. It’s not known how much plastic it takes to kill a leatherback, but two facts are clear: no animal can digest plastic, and the amount of plastic in the oceans is increasing drastically every day.
It’s not all bad though, the barrel jellyfish helps out little crustaceans called amphipods (Hyperia galba) by letting them hitch a ride and stay safely hidden to avoid being eaten by fish.
So, with lots of food (plankton) available to eat, nothing around to eat them and with the seas getting warmer, conditions are just right for all jellyfish types to grow up and swarm together to form ‘blooms’ which are being seen more often around the world.
Why do they end up on the beach?
This is thought to be because of an increase this year in food (plankton) available close to the shore which coud be due to heavy flooding washing nutrients into the sea. Jellyfish don’t really swim or move around with much purpose either so they tend to drift where currents and strong winds take them. This means that they’re susceptible to getting stranded when the tide goes out.
What should you do if you see jellyfish on the beach or in the sea?
- Don’t panic! While they may be large, barrel jellyfish are not harmful enough to hurt humans. Whilst these and some others are harmless and may only have a mild sting, there are others that have a painful and even dangerous sting so it is not advisable to touch them. If you do, make sure you are protected and use gloves or a stick and stay away from the stinging tentacles
- It would be useful to identify what type you have seen so take a picture if you possible. Here is an identification guide produced by the Marine Conservation Society for the most common types of jellyfish. When you can, go online to complete the MCS jellyfish survey which will help with really important research regarding the decline of leatherback turtles
- If you do get stung, the most consistent advice I found was to put shaving cream on it! (fascinated to know how many people carry this around with them on the beach!) This prevents toxins from spreading. The old wives tale of urinating on it or using vinegar is not helpful and only serves to make the toxins more reactive. Try removing any remaining tentacles/stinging sacs by scratching them off with a credit card or shell. There is conflicting advice regarding the use of water and ice packs but they may help to reduce swelling. The NHS has guidelines here but basically you only need to seek medical attention if there is difficulty breathing, chest pain or if the sting is over a large or sensitive area such as face or genitals
- Leave them alone. Left undisturbed, barrel jellyfish will recover when the tide re-floats them and they will drift away out to sea again. If they are dead, the advice is to leave them for the ‘authorities’ to move them away safely
Have you ever been stung by a jellyfish? What did you do to treat it?