Dick Raynor's Dores Bay Film, Loch Ness

In the 1960s the Loch Ness Investigation Bureau kept watch on the loch. Its base was a hillside camp at Achnahannet. Mobile camera units waited at viewing points along the shore, loaded with 35 mm film. Dick Raynor was one of the volunteers behind those cameras. In 1967 he was an observer and camera operator, and he would become a staff member in 1971.

13 June 1967. Dores Bay, at the northern end of Loch Ness. Conditions on the loch were very good. The water was calm. Then a disturbance appeared on the surface, about one mile from Raynor's camera. He filmed it with a 35 mm cine camera fitted with a 17-inch lens.

On the film, a clear wash or wake can be seen before and after the tour boat Scot II passes into view. The disturbance was about half a mile from the boat. According to Raynor, its passengers would not have seen it. They were too low to the water.

In his sighting report Raynor recorded "an impression of one object at the front of the disturbance and other objects catching up with it at times." No animal was visible. Only the wake, and whatever was making it.

The Bureau sent films of interest to JARIC, the Joint Air Reconnaissance Intelligence Centre of the Ministry of Defence. Raynor's footage was judged the best of them. JARIC concluded it might show an object as much as 7ft (2.1m) long. That was more than any animal known to live in Loch Ness.

Roy Mackal, the Bureau's scientific director, agreed that it stood apart. In The Monsters of Loch Ness he dismissed most LNIB films as inconclusive, birds or waves. Raynor's film he classed as positive evidence.

The answer came from an unexpected direction, the cameraman himself. Raynor later concluded that he had filmed a family of red-breasted mergansers, diving ducks. Spread out, a group of them often measures around 2 metres, which, he noted, fits the JARIC figure. Adrian Shine of the Loch Ness Project describes a hen merganser leading her chicks in tight formation, and chicks that sometimes run across the water to catch up. It echoes the 1967 note of objects catching up with a leader.

On a calm day, Raynor argued, the disturbance is visible well over a mile away, while the birds stay beyond even top quality optics. "Only the failure of the camera system to resolve the individual birds at a range of one mile prevented, in my opinion, that particular mystery from being solved at that time."

Not everyone is convinced. Viewers on Roland Watson's Loch Ness Mystery blog called the wake very powerful and the movement creature like. "I just cant see birds leaving wakes like that," one wrote. Another found the film inconclusive, mostly because of its low quality.

No one has accused Raynor of faking anything. As one viewer put it, he stood to gain nothing from debunking his own film. That is what makes the case unusual. The witness, the Bureau's best film and its most detailed explanation all come from the same man. Raynor became a long-time researcher and diver at Loch Ness. His footage sits in the record beside Tim Dinsdale's 1960 film and the other LNIB reels of the decade.