Beaches yes, but without jellyfish! On the principle, I understand you, but in reality, it is not easy. Because, if summer is a promise of vacation and idleness to the beach, it also attracts gelatinous, sometimes bulky roommates … and poisonous! Indeed, scientists have found that climate change is accompanied by an increase in poisonous aquatic species, such as jellyfish, on our coasts. So what to do? What are the good practices to adopt?
Already, let's take an interest in this term “Medusa”. In reality, it does not designate a specific animal. It is an umbrella name, or vernacular, which encompasses many forms of cnidaires. These are animals with stinging cells, called cnidoblasts.
The jellyfish have a gelatinous appearance. They have neither skeleton, nor brain, nor lungs. However, it should not be believed that they come down to a single hat (shadow) and some tentacles. In reality, their structure is complex.
The jellyfish are generally predatory and trap their prey with their stinging tentacles. Cnidoblasts contain a toxic liquid which is injected into the prey thanks to a kind of mini-harpoon. These cells only work once; When they “harp” a prey, they remain hung. The jellyfish must therefore reconstruct regularly are a stock of stinging cells.
At the beginning of the 21st century, there were about 1,500 species of jellyfish. Almost all are poisonous, but some are more than others. Cubomeduses (whose name is inspired by their cubic shame) are particularly dangerous. An Australian species, Chironex Fleckeri Also called sea wasp or death, can kill an adult in two minutes.
French jellyfish are less dangerous, but their bite still remains painful.
Cubomeduses, or box jellyfish, are extremely dangerous and can kill an adult in two minutes.
Credits: Shutterstock/Henryp982
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Jellyfish well installed on the French coast
From the North Sea to the Mediterranean, the jellyfish are indeed present. There are several species on our coasts, some being more common than others.
Among them, we notably observe the pelagic jellyfish, Pelagica Noctulica. Violet, its umbrella is blue and pink. It is the most stinging species of our seas. It is found mainly in the warm waters of the Mediterranean and sometimes in the Atlantic Ocean. Normally, it sails offshore, but the winds and currents can bring it closer to the ribs. Beware then to its tentacles, because the bite is burning and painful.
The radiated jellyfish, Chrysaora hysoscellais a little less stinging than the pelagic jellyfish. Despite everything, it is better not to rub it. We find it all over our coasts, especially in the spring.
A very common and not very stinging species is the Medusa Aurélie, Aurelia Aurita. She lives both in the open sea and near the coasts and it is quite common to observe it in ports or estuaries. It has a translucent white-blue color. In the center of its umbrella is a 4 -sheet clover -shaped structure whose color varies depending on sex. Violet in males, whitish in females.
Rare fact, to underline, there are harmless jellyfish! This is the case of the cauliflower jellyfish, Rhizostoma Octopus. Its color varies between yellow, brown, blue and green and … it has no tentacles! It is a large species, which can be observed on almost all our ribs, often in lagoons and estuaries.
Finally, we can cite the blue cyana or hair jellyfish: Cyanea Lamarckii. Present almost everywhere, except in the Mediterranean, she has many tentacles. The latter are often long and very fine, which makes them almost invisible … Painful trap for bathers!
>> Read also: What are the jellyfish who proliferate in France?
More and more animals …
You may have noticed, we observe more and more jellyfish on our beaches in the summer season. The fault … climate change!
Scientists have indeed alerted to this effect of global warming. An increase in poisonous species, whose jellyfish, awaits us. A GIEC study and report attest to it.
This is particularly due to a change in the range of aquatic species. With the warming of the oceans, the waters close to the equator will become too hot. Animals will therefore migrate to more welcoming ocean regions. This is also the case for jellyfish.
Despite everything, they also benefit from warming water and their acidification. In particular certain species that we would not like to see swarm. Like the famous Cubomeduse, or Boast Medusa, which I told you about previously. The jellyfish appreciate these new conditions and reproduce much more.
In addition, overfishing and loss of marine biodiversity make the predators of the jellyfish become scarce. The pollution engendered by worn and fertilizers provide nutrients that algae and certain plankton love, privileged food of gelatinous creatures. The larvae also love plastic, to which they adhere, before becoming a jellyfish. The animals therefore adapt very well to the degradation of the oceans.
In view of these conditions, not surprising that the jellyfish swarm … We will therefore have to take precautions during swimming!
>> Read also: jellyfish: the reasons for their proliferation
What to do in case of bite?
If you get bitten by jellyfish, forget everything you have been taught. Il.ne.faut.pas.se.faire.pipi.dessus! This is the first idea that comes to mind (thank you Friends ?). However, it's a false good idea. Admittedly, the heat of the urine will be able to relieve for a moment, but its composition is likely to burst the stinging cells which have not yet “caught up” the skin.
You should also avoid fresh water. Like urine, it can burst the remains of stinging cells. Only seawater avoids this effect!
Then, above all, we don't scratch! This may be hard, but if you scratch, you come into contact with the stinging cells present and it is the hand that will then be stung. So, after rinking, we put (we don't rub!) Sand in the painful area and let it dry. A little later, you can scrape the sand with a rigid object, like the famous shovel of sand castles, to eliminate the stinging cells. We finish by rinsing one last time in sea water.
Coming back, by acquired conscience, do not hesitate to disinfect the wound. On the other hand, the antiseptic should not contain alcohol. The latter will accentuate the burning sensation.
If, despite everything, you observe a strong reaction, consult a doctor. And, in any case, as far as possible, do not approach jellyfish, even dead and stranded on the beach.
And, if you want to know more about the state of the beaches, there is a collaborative card. Meduseo thus informs you, almost in real time, of the quantity of jellyfish on our coasts.
>> Read also: toxicology: the bite of this jellyfish will no longer be fatal
With an unwavering passion for local news, Christopher leads our editorial team with integrity and dedication. With over 20 years’ experience, he is the backbone of Wouldsayso, ensuring that we stay true to our mission to inform.
