A hammerhead shark has been spotted in British waters for the first time ever, according to scientists.

The shark which has a distinctive flattened head was seen in the Celtic Sea about 100 miles southwest of Ireland.

The shark was seen on the surface of the sea for a just few seconds. It was just enough time for two nearby marine scientists to positively identify the predator by its unique dorsal fin.

The rare sighting comes amid predictions that the predators could become regulars in UK waters by 2050 as sea temperatures rise. 

Hammerhead sharks can grow up to 20ft in length and usually live in warm tropical waters in the Caribbean and off West Africa.

The sharks migrate to cooler seas in the hot summer months.

According to experts, the lone shark was probably lost but had likely ventured further north than usual due to the increase in sea temperature. 

The arrival of the hammerhead could mean that hammerheads and Great White sharks may be seen in UK waters in the not-too-distant future.

The hammerhead was sighted near the surface while experts from Galway’s Marine Institute were conducting an annual survey of herring stocks.

Marine mammal observer, John Power shared, "While scanning the surface, we sighted a dorsal fin unlike anything we had encountered before. It was quite different from the fins on basking sharks and blue sharks. After consulting available ID keys, we agreed that the shark must be a smooth hammerhead," reported The Sun.

Dr Simon Boxall, of the Southampton Oceanography Institute, added that future hammerhead sharks would be able to survive off the UK coast.

He shared that the sightings did not come as a surprise to him given the fact that ocean temperatures are rising. "Temperatures in these waters have increased by 2.5C over the last 20 years and more exotic species carried by the Gulf Stream are travelling further north for food," Boxall shared. 

He further added that it is highly probable that more shark species such as hammerheads and Great Whites do exist in the British waters but they have not been spotted yet.

He also shared that hammerhead sharks are not really interested in humans and attacks on humans are rare. 

The species is listed as “vulnerable” on the International Union for Conservation of Nature Red List of Threatened Species.