When it comes to the ocean, people often think they need to travel to far-flung, exotic locations to see incredible wildlife but the UK is home to lots of amazing –and enormous – marine life says Melissa Hobson
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From whales the size of a bus to breaching sharks with whip-like tails, here are some of the UK’s most colossal ocean animals.
Largest sea animals
Basking sharks (Cetorhinus maximus)
Reaching 12 metres, basking sharks are the world’s second largest fish - behind whale sharks. When these ocean giants cruise the surface feeding on plankton, it looks like they’re basking in the sun. They usually visit UK waters between May and October and can be seen in Cornwall, the Isle of Man and the Sea of the Hebrides
Killer whales (Orcinus orca)
Also called orcas, killer whales are the largest and, arguably, most recognisable dolphin. They grow up to 9.8m long with an enormous dorsal fin (up to 1.8m in males) and iconic black and white markings. A resident group lives around the west coast of the UK and Ireland and another population sometimes visits northern Scotland.
Are killer whales dangerous to humans?
Humpback whales (Megaptera novaeangliae)
Humpback whales can grow to 17m – around the same length as a bus. The markings on the underside of their tail fluke are unique to each whale so researchers use these to identify individuals. Humpbacks feed in colder waters before making huge migrations to tropical oceans to reproduce. They can sometimes be spotted in UK waters, particularly in Cornwall.
Atlantic bluefin tuna (Thunnus thynnus)
For 60 years bluefin tuna weren’t found in British waters after being wiped out by commercial fishing. Thanks to fishing quotas, their populations have bounced back and they have been seen off our coast again. These gigantic fish can reach 4.5m and are known for their astonishing speed – hitting 40 kilometres per hour at top speed.
Sunfish (Mola mola)
If you imagined slapping a face on the side of an old pancake and throwing it into the ocean, you’ve got a pretty good picture of a sunfish, one of the world's weirdest fish. These three-meter animals have a round, rudder-like fin at the back which looks like its tail is missing. In the UK, you might be lucky enough to see one of these weird creatures on a boat trip from Devon or Cornwall.
Sperm whale (Physeter macrocephalus)
These huge whales, which grow to 18m, have the biggest brain of any animal on the planet. Inside their heads is an oily fluid called ‘spermaceti’, which scientists once thought was sperm - hence the name. They can dive over 3,000m hunting their favourite food: squid. While found in UK waters, sperm whales are rarely seen unless they get into trouble and strand.
Leatherback turtle (Dermochelys coriacea)
Another deep-diving animal, leatherback turtles are the world’s largest turtles and can grow over two meters. Leatherbacks can plummet to depths of over 1,200m, compared to other sea turtles which don’t exceed 290m. This is why they don’t have a hard shell: the ridged, leathery skin on their backs compresses in deep water when a shell would crack under the pressure. Although rare, you can see these gargantuan turtles off the west coast of the UK.
Thresher sharks (Alopias vulpinus)
The Indiana Jones of sharks, threshers (one of the world's weirdest sharks) have a 3m long, whip-like tail that they use to stun their prey. The tail is half the length of the entire 6m shark. Threshers can leap clear of the water in a massive breach. This rare spectacle was once caught on camera by lucky tourists on a dolphin watching tour off Cardigan Bay, Wales.
Barrel jellyfish (Rhizostoma pulmo)
Also called dustbin jellyfish because of their tremendous size, these 90cm jellyfish can weigh an epic 35kg (around the same as a Doberman). They like warm waters so can be found here from May to October, when huge swarms can wash up onshore. It’s the most common jellyfish seen in UK waters.
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Angelshark (Squatina squatina)
Angelsharks are broad and flat, looking more like a ray than a shark. Found across Europe
and the UK, they often live around continental shelves (down to around 150m) and grow to
2.4m. These lie-in-wait predators hide in the sand until their prey swims past then snap it up.
The critically endangered species is protected in England and Wales.
Read more about the world's most fascinating marine life
