A snorkeller was bitten by a shark off the West Cornwall coast on Wednesday – but how common are they and what species can we expect to see?

The snorkeller was met at at Penzance harbour by the ambulance service after having suffered a leg injury during the encounter.

In an update posted on its social media page, Blue Shark Snorkel Trips said: "We want to make everyone aware that we have had an incident.

"These occurrences are extremely rare and can be easily misunderstood so we want this to be dealt with as sensibly as possible.

"As we know, these things can happen when we choose to interact with wild animals in their own environment."

There are more than 400 known species of shark in the world.

Rhyl Journal: A fin of a 'great white shark' has been spotted just yards off the coast from a popular beach, it has been claimedA fin of a 'great white shark' has been spotted just yards off the coast from a popular beach, it has been claimed

More than 40 different species of shark pass through UK waters, but only 21 of these can be found all year round.

Here are several species that have been spotted in recent years:

1. Basking shark

The basking shark can reach lengths of up to 12 metres and is second in size only to the gigantic whale shark.

These gentle giants are filter feeders, mostly dining on plankton. 

Basking sharks do not actively seek out food or suck in water, instead they swim with their mouths open, catching whatever goes through.

The basking shark is a seasonal visitor to the UK – the best time to spot one is between May and October, when a significant number of them arrive in British waters.

Basking sharks live for around 50 years and often swim around either in pairs or groups of up to 100.

2. Porbeagle

The porbeagle is one of the most common types to be spotted.

Its distinctive dorsal fin and long powerful body are among the characteristics that make the creature resemble a great white.

Rhyl Journal: The porbeagle shark gliding majestically through Plymouth's Mayflower Marina. Picture: SWNSThe porbeagle shark gliding majestically through Plymouth's Mayflower Marina. Picture: SWNS

There has never been a confirmed case of a porbeagle killing a human, as the predators feed on smaller fish.

3. Dogfish

Known as one of the most unfussy eaters of the ocean, the dogfish feeds on pretty much anything it can catch: prawns, worms, small fish, and crustaceans.

The dogfish is one of the most common types of shark found in UK waters.

They are usually found around the southern and western waters of the British Isles.

Rhyl Journal: A dogfish shark that washed up on a Kent beachA dogfish shark that washed up on a Kent beach

Despite its name, it doesn’t actually look like a dog.

It has a long, slimy body with skin that is very rough to touch. 

5. Spurdog

You’ll catch this species of shark feeding along the bottom of the seabed and only venturing to midwaters to feed on prey such as sprats and herring.

The spurdog is known to swim around in shoals, which helps it to cover large distances when looking for food.

Rhyl Journal: A spurdog sharkA spurdog shark

The spurdog has two dorsal fins that release venom – it’s one of the few venomous fish found around the UK.

Its venom can cause extreme discomfort and swelling in humans. 

6. Shortfin mako shark

The shortfin mako is the fastest shark in the sea, thought to be able to reach swimming speeds of nearly 50mph.

These sharks are apex predators, sitting at the top of the food chain, and their speed enables them to catch fast-swimming prey such as tuna and swordfish.

As well as being able to dive to depths of more than 400 feet, they can jump as high as 20 feet out of the water. 

Shortfin makos are spotted in waters all over the globe, and – although rare – are found from time to time in the seas around the UK and Ireland.

7. Tope

Growing up to 6ft long, the tope has a streamlined body with a distinctive, long snout.

It is known for its aggressive, powerful presence, and for being an extremely strong swimmer.

Rhyl Journal: Fisherman Mick Frost with a heavyweight tope, weighing in at 45lb 5ozFisherman Mick Frost with a heavyweight tope, weighing in at 45lb 5oz

It is only during the mating period that male and female topes socialise – the rest of the time they are separated by gender.

8. Smooth-hound

Also known as gummy sharks, smooth hounds are found in waters off the coast of South and West England.

Swimming in shallow waters, they favour sandy and shingle seabeds.

Despite their shark-like appearance, smooth-hounds are not scary, underwater predators.

Feeding mainly on crustaceans, smooth-hounds do not have razor-sharp teeth.

Instead, it has powerful crushing plates which help them get all the nutrients they need to complement their diet.

Full list of sharks found in our waters:

From the Shark Trust:

• Porbeagle Shark

• Smallspotted Catsharks

• Nursehounds

• White Shark

• Portuguese Dogfish

• Black Dogfish

• Birdbeak Dogfish

• Rough Longnose Dogfish

• Sailfin Roughshark

• Angular Roughshark

• Longnose Velvet Dogfish

• Knifetooth Shark

• Kitefin Shark

• Gulper Shark

• Spurdog

• Leafscale Gulper Shark

• Basking sharks

• Blue Shark

• Shortfin Mako Shark

• Smooth Hammerhead

• Frilled Shark

• Thresher Shark

• Bigeye Thresher Shark

• Oceanic Whitetip Shark

• Common skate, blue skate

• White Ghost Catshark

• Mouse Catshark

• Bramble Shark

• Velvet Belly Lantern Shark

• Tope Shark

• Blackmouth Catshark, Blackmouth Dogfish

• Smalleye Catshark

• Iceland Shark

• Nurse Shark

• Sharpnose Sevengill Shark

• Bluntnose Sixgill Shark

• Starry smoothhound

• Small-spotted Catshark

• Greenland Shark

• Spiny Dogfish

• Angel Shark

• Smalltooth Sandtiger

• Tiger Shark

• Scalloped Hammerhead Shark

Those that can be a bit more dangerous are the Oceanic White-Tip Sharks, the Nurse Shark, the Sharpness Sevengill Shark, the Shortfin Mako Shark, Blue Sharks, Nursehound Sharks and Angel Sharks.

What to do if you spot a shark?

Stay still

If you spot a shark stay as calm as possible. Most sharks will leave on their own, if you stay quiet.  Unprovoked shark attacks on humans are rare.

Attack back, only if attacked

Do whatever it takes to get away without making noise or splashing. Startle it by punching it in the nose, claw at its eyes or grab its gills; the most sensitive areas of a shark.

Don't turn your back

Whatever you do, don't take your eyes off the shark. They have many surprise tactics such as hit-and-run or bump-and-bite.

Report it

If you spot a shark from the beach, report the sighting to the local harbour patrol along with the dimensions and location of the shark.

The last recorded shark attack in the UK occured in 2016, when a windsurfer had their board bitten. The surfer in Suffolk was not injured.