Shark season is in full swing off the coast of Donegal as Irish researchers have successfully deployed a video camera on the fin of a basking shark in what they say is “a world's first.”

The camera was deployed by a team from the Irish Basking Shark Project on the dorsal fin of a six-metre basking shark last Thursday, just south of Malin Head in County Donegal.

It was recovered via a mini VHF directional finder 25 hours later on Friday 19 July, about five miles west of the initial deployment site.

Emmett Johnston, a spokesman for the team, said: "We got about 3 hours of footage, plus body acceleration, roll and movement data which we are correlating with the video footage."

"We haven't seen sharks in such good numbers since 2010. The good weather has brought the sharks to the surface for longer periods and created suitable conditions for large aggregations to form.”

“The sharks are gathering in the many small bays and inlets on the north coast to feed on the dense clouds of plankton, literally yards from the shore line."

One local kayaker had a remarkably close encounter with one of the seasonal visitors last week.

Graham Smith was fishing from his kayak in Tullagh Bay, off Inishowen, last Thursday when he encountered the shark.

He managed to film the shark for several minutes as it apparently fed in the slipstream of his vessel.

"What an amazing experience a basking shark made three attempts to swim with my kayak and I only realised what he was at on his third attempt, he was so close and seemed to like being beside the kayak," Mr Smith, who posted his video on YouTube, said.

The basking shark is the largest fish in the Northern Atlantic and the second largest in the world.

Its average size is 5m-7m, although some specimens have been recorded at 11m.

It is characterised by its large dorsal fin and docile surface swimming behaviour.