A voice speaks over a film of deep water. "There is a creature alive today who has survived millions of years of evolution without change... It will attack and devour anything!"

This is a trailer for the blockbuster 1975 movie Jaws. It tells of an American seaside resort terrorised by a great white shark. Now some experts are predicting that great whites could be coming to British waters.

Britain already has a huge number of sharks: according to some estimates, 10 million small ones and 100,000 larger ones. Many are small and quite harmless.

Great whites, which can grow to five metres in length, are a different matter.

In the US, great whites are a growing concern. Five attacks were recorded off Cape Cod, on the east coast, in the last 12 years - one in which someone died.

The worry for Britain is that our sea provides a very similar habitat. An organisation called Ocearch, which tracks shark movements, believes that great whites may now be heading for these shores. 

This is partly because Britain has a lot of seals - over 130,000 according to experts. And seals are a big part of some sharks' diets.

Water temperature is another factor. With global warming, sea temperatures are rising, and could become perfect for great whites.

Experts say that sharks should be more afraid of us than we are of them. More than 100 million are killed around the world each year, and the population is falling as a result of overfishing, climate change and plastic pollution. 

Should we welcome them?

Yes! Sharks are extraordinary creatures which very rarely attack humans.

No! Even one person killed by a shark is one too many.