In a clip shared on TikTok, the basking sharks could be seen swimming in the shallow waters of Keem Bay on County Mayo's Achill island.
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Beautiful and terrifying
In the clip, shared by TikTok user @k.m.m.hairstyles, several beachgoers can be heard saying: 'Oh my God,' as others continue to splash around in the water.
Basking sharks, which can grow up to 26ft in length, may look a bit scary but they're actually completely harmless, unless you happen to be plankton.
The huge sharks are not aggressive and pose absolutely no threat to humans, but fellow TikTok users were still left feeling pretty shaken up after seeing the footage.
One person wrote:
I know they aren't dangerous, but they are still unsettling! Beautiful and terrifying.
Another said:
Welp, I'm never going in the ocean again.
While a third person posted:
That's it, I'm not going to Irish beach!
Sharing the footage on Twitter, one man described it as 'a scene from Jaws.'
Earlier this year, American musician Alex Albrecht, shared footage of an absolute whopper of a basking shark, prompting some to believe it was a, now-extinct, megalodon.
Albrecht, who had been sailing around the Atlantic Ocean, shared a video of the massive shark captioning it:
Sailed six weeks in the Atlantic saw this big f***ing shark.
Well, at least that's an accurate description of it.
Megalodon
In response, one person said:
Is that megalodon?
No, sorry to disappoint, but the fish lived between 23 and 3.6 million years ago before going extinct.
Megalodons could measure up to 20.3 metres and had an unbelievably powerful bite.
However, more sensible TikTokers pointed out:
It's a basking shark.
With another adding:
Basking sharks are harmless to humans but they weigh a s*** ton.
Basking sharks don't hibernate and are active all year round, which is why they're often spotted by beachgoers and sailors.
Usually they're seen in the summer months, as when it becomes cooler they tend to swim deeper into the ocean to feed.