This is the moment a 5-foot-long shark was seen just 30ft from one of Britain"s most popular beaches, writes dailymail.co.uk.

The porbeagle shark, a relative of the great white was observed for 25 minutes feeding in the relatively shallow water off Southbourne beach in Bournemouth.

Usually, Porbeagles are seen miles out at sea by fishermen and have little interaction with humans.

It is highly unusual for one to come so close in and it is likely it was following a rich food source. They normally feed on squid and other cephalopods and one theory is that it could have been lured by the recent mass influx of Mediterranean octopus of the south west coast.

The porbeagle was filmed from the shore by Jonathan Brennan, who is a qualified PADI scuba diver and who has swam with sharks all over the world. He confidently identified it as a porbeagle after ruling out it being a tope or a basking shark, both commonly seen in south coast waters. Despite it being seen so close to a popular bathing beach at the start of the summer season, 55-year-old Mr Brennan said its presence was good news: “It is a sign of a healthy ecosystem”.

Along with blue sharks, porbeagles are the most common species of shark found in British waters. Despite their association with the great white - Carcharodon carcharias in Latin - they are not considered to be a threat to humans with only three recorded non-fatal attacks before. The porbeagle shark - Lamna nasus in Latin - is classed by the International Union for Conservation of Nature as vulnerable in the north east Atlantic.