Donate now

Stings, spines and sharp teeth: Sealife you might meet this summer

The seas around the UK and Ireland are home to some fascinating creatures. Here’s how to deal with some of the coastal encounters you might have this summer.

Sea creatures you might meet this summer

The coasts of the UK and Ireland are some of the most scenic and beautiful in the entire world. From dramatic rock formations to long stretches of golden sands, it’s no wonder so many of us spend our summers at the seaside. But we aren’t the only ones. We share our seas with a huge variety of different sea creatures. And while we won’t even know that most of them are there, more people at the coast means more unpleasant encounters.

The good news is that the sea creatures in our waters aren’t actively out to get us. In fact, most encounters will be perfectly harmless. But, if you do get stung by a jellyfish, tread on a weever fish, or come face-to-face with a shark, there are things you can do to ensure that both you and the sea creature are left unharmed.


Compass jellyfish


Simultaneously one of the strangest and most beautiful type of sea creature, jellyfish have a fearsome reputation based on their stinging tentacles. But the vast majority are entirely harmless to humans, with only a few species able to cause us harm. 

There are six main species you can find in UK and Irish waters.

The one you’re most likely to bump into is the moon jellyfish. These are the most common species and can grow to the size of a side plate. You can recognise them from the four circles visible inside the centre of the creature. Barrel jellyfish are the biggest species you’ll find in the waters around the UK and Ireland. They feed on plankton in deeper water but can drift into the shallows on the tide.

The lion’s mane jellyfish is one of the few types that can cause you damage. It gets its name from the thick layer of hair-like tentacles that ring its body. These tentacles can cause some serious pain if you come into contact with them.

A species that isn’t native to the UK and Ireland but sometimes finds its way here is the Portuguese man o’war, which has tentacles that can stretch over 30m. While not technically a jellyfish, they are often labelled as such. A sting from one of these can leave you in agony for several hours.

What to do if you get stung by a jellyfish

At certain times of year, jellyfish blooms come close to shore and it can be hard to avoid them in the water. If you know you’ll be in the sea with jellyfish, minimise the amount of exposed skin to reduce your chance of stings. Wetsuits offer good protection and rash vests will shield you from most jellyfish tentacles. 

But that’s not the only way people get stung. A jellyfish washed up on the beach may seem like a good photo opportunity but you can still be stung when handling them – even if you’re certain they’re dead.

The good news is that RNLI lifeguards are trained to deal with jellyfish stings. So if you’re visiting the coast for a swim, make sure it’s at a lifeguarded beach. If you do get stung, here’s what the lifeguards will do:

Scrape off any remaining tentacles: Make sure you remove any tentacles still attached to your body but be careful not to rub them into the skin, as this will cause more damage.

Apply cold sea water: This should help alleviate the pain. Do not urinate on the sting. This is not effective and only works in films and TV shows!

Avoid applying fresh water or cold packs: This will not do anything to help and could make it more painful.

Once you’ve had your sting treated, you might be asked to wait for half an hour to ensure you don’t have an allergic reaction to the sting.

Weever fish

Weever fish submerged in the sand

Simon Rogerson

One of only a few species of venomous fish found in the UK and Ireland, the lesser weever fish spends most of its day buried in the sand. With eyes on top of its head, it lies in wait for its prey, before bursting through the surface of the sand and attacking.

Their dorsal fin contains three spines containing a venom, which the weever fish uses to defend itself. It buries itself in the sand leaving its dorsal fin exposed pointing upwards. This protects the fish from any potential threats. Unfortunately, that threat is often the foot of someone going for a paddle along the shoreline.

What should you do if you get stung by a weever fish?

Lifeguards treat a weever fish sting

RNLI/Nathan Williams

An RNLI lifeguard treats a weever fish sting

The level of pain varies between people depending on the amount of spines that have punctured the skin and the pain tolerance of each individual. ‘I have treated toddlers who are quite content with their foot in a bowl of warm water but have also seen adults in tears. I have also had to treat an unfortunate gent who had actually sat on one,’ says Brett Shepherd, Operations Manager (Lifeguards). 

So what can you do to alleviate the pain?

Immerse injured limb in warm water: Keep the injury in the water until the pain becomes bearable.

Wash area with warm soapy water: This will help clean the wound of any dirt.

Check and care for the puncture wound: You may need to bandage the area. 

Remember, all lifeguards are trained to treat weever fish stings – just another reason to always visit a lifeguarded beach! If you aren’t at a lifeguarded beach and have a reaction to a sting by a weever fish or jellyfish, you should call 999 or 112 and ask for an ambulance.


A blue shark swimming in the ocean

Elianne Dipp, Pexels

If there’s one thing that people fear most in the water, it’s sharks. The idea that you’ll see a distinctive dorsal fin break through the water’s surface nearby is enough to put some people off swimming completely. 

Sharks have a bad reputation, and it’s unfounded. You’re more likely to be struck by lightning or win the lottery than you are to be bitten by a shark. And cows kill far more people than sharks every year. In fact, overfishing and demonisation of sharks has led to many species becoming threatened or endangered and listed as priority for protection.

There are many species of shark native to the UK and Ireland. Some of the more famous ones include several types of dogfish and catshark species, and you can often find their eggcases washed up on the beach. Blue sharks are one of the more common predatory sharks in our waters but spend most of their time out in the Atlantic Ocean so are still a rare sighting. The basking shark is one of the largest species of sharks on the planet. Completely harmless, they feed on plankton by filtering sea water through their huge gaping maws.

Occasionally, you might hear about a great white shark being spotted off the coast. These are often just scare stories - the only scientifically recorded great white was found 168 miles off the coast of Cornwall in 1977.  

Nursehound shark lying on the sea bed


Nursehound sharks are another of the species native to the UK and Ireland

What to do if you come face-to-face with a shark

According to a report written by the Shark Trust, not a single unprovoked shark bite has been recorded in British waters since 1847, when records began. But what should you do if you do have an encounter with a shark? The good news is that, in UK and Irish waters, you are not likely to be of any interest to a shark. In fact, they are likely to be more wary of you than you are of them and will probably have disappeared long before you noticed they were even nearby. But in the unlikely scenario you do come face to face with a shark, either at home or on holiday abroad, here’s some advice on what you should do:

  • Always swim at a lifeguard patrolled beach and between the flags. 
  • Leave the water immediately if a shark is sighted. 
  • Never swim alone. 
  • Never swim at dawn, dusk or at night. 
  • Never swim in murky waters. 
  • Do not swim near schools of fish. 
  • Do not swim in tidal rivers or near a river mouth. 
  • Do not swim near, or interfere with, fishing equipment. 
  • Do not swim if you are bleeding.


Lundy grey seal


At the other end of the fear scale are seals. Often seen as cuddly and cute, these creatures are wild animals and can give a nasty bite if threatened. You might find them lounging on the beach or rocks at the coast this summer. While it may seem like the perfect photo opportunity, you should stay a safe distance away, especially if there are young seal pups with protective parents. The two most commonly found species are the common seal and grey seal

What should I do if I come into contact with a seal in the wild?

Whether you find a seal on the beach or in the water, you should keep a distance. There’s a common misconception that if a seal makes eye contact with you, it’s because they’re curious. In fact, it’s because their fight or flight response has been activated. The seal is weighing you up as a potential threat.

You should keep well away from any seals you spot in the wild. Ideally so they cannot hear, see or smell you. Use cameras or binoculars if you want to get a closer view. If there’s a dog with you, keep it on a lead.

There’s a real danger of the seal hurting itself or other seals if you cause it to panic. Groups of seals can stampede towards the water if scared, meaning any weaker ones or seal pups can be trampled in the panic. If you spot a seal, you should back away slowly and give the seal space to move off in its own time, if at all.

Do not approach any seals in the water. Any sort of disturbance can cause a seal to raise their stress levels, and waste energy that it may not be able to recover. You should also never feed seals, as it is dangerous for both them and us. Sue Sayer, from the Cornwall Seal Group Research Trust, explains: 'A seal’s eagerness to be the first to snatch the dangling fish from our hands increases the risk of them misjudging distances at speed, which could result in accidental injuries. Seal bites are extremely serious and always require medical attention.' Learn more about seals and how to keep them safe.

Stay safe, have fun at the coast

Give sea creatures space and enjoy them from a distance. Most marine species aren’t inherently dangerous. Not just in the UK and Ireland, but across the globe. It’s mainly media hype that causes us to fear them unnecessarily. Many are protected species and deserve to be left alone so that they can continue on and keep their delicate ecosystems balanced. As long as you treat sea creatures with respect, both you and them can go about your visit to the seaside without incident. 

If you’re visiting the coast this summer, choose a lifeguarded beach. That way, if you do get stung, there are experts on hand who can provide you with the care and treatment you need to help deal with the injury.

Find your nearest lifeguarded beach using the RNLI’s search tool. And if you want more advice on how you can stay safe at the coast, visit our beach safety pages for the latest and best advice.