Extraordinary video footage has been released showing up to 50 sharks swimming together just off the coast of southern England.

The video, filmed by the RSPB Medmerry wildlife site on 15 July, shows a massive shiver of sharks swimming in the shallow intertidal waters near Selsey in West Sussex.

The RSPB's warden, Peter Hughes, who was able to capture the footage, described the scene.

"It was astonishing. There were just these huge fish everywhere in knee-deep water," he said.

"We knew in time that Medmerry was going to be a great place for wildlife, but I don't think anyone expected this. We assume they were coming in to feed on the crabs and other marine life that have made their home at Medmerry," he added.

The smooth-hound sharks featured in the video can measure up to 1.5m (5 ft) in length and weigh 13 kg (29 lb). They are often found offshore in coastal waters.