A basking shark was photographed near Flamborough Head yesterday by Chrys Mellor, an RSPB volunteer who was aboard the Yorkshire Belle, which operates birdwatching cruises near the Bempton Cliffs nature reserve.
It is only the third time Chrys has seen a basking shark in the area since he began volunteering on the boat 30 years ago.
The species is the world's second-largest type of shark - behind the whale shark - and can grow up to 26ft in length, but eats mainly plankton and is not dangerous to humans. They live in most of the world's temperate oceans.
Fittingly, the cruise was the Yorkshire Belle's final trip of the summer season.
The warm summer and calm weather has led to an unprecedented number of shark, whale, dolphin and porpoise sightings off Yorkshire's coast this year.
Earlier this month, a fisherman in an inflatable dinghy took this video of a porbeagle shark which circled his boat during a fishing competition in Runswick Bay, near Whitby.
While passengers on charter boat Three Sisters filmed a minke whale during a cruise off Staithes.