The Loch Ness Monster and the Surgeon's Photograph

Loch Ness is one of the most searched bodies of water on Earth. For nearly a century people have scanned it with cameras, sonar and, most recently, DNA samples, looking for the creature that has made a Scottish lake a world-famous name.

The search has produced a great deal of evidence, though not of a monster. It has told us how the legend began, how its most famous image was faked, and what is probably behind many of the sightings.

An old story

Supporters of the monster often point to Saint Columba. In the seventh century the abbot Adomnán wrote a Life of St. Columba describing how the saint, in 565, drove off a water beast in the River Ness. Sceptics note that confronting monsters is a common motif in the lives of saints, and that the episode is not evidence of an early local tradition about a creature in the loch.

Either way, there is no continuous record of a monster between Columba and the twentieth century.

The summer of 1933

The modern legend starts with a newspaper report. On 2 May 1933 the Inverness Courier published an article by Alex Campbell describing what Aldie Mackay and her husband had seen in the loch on 15 April, while driving on the road along its shore. In July another couple, the Spicers, reported a creature crossing the road, and the story spread rapidly.

It is often said that a new road along the loch that year brought crowds who had never seen it before. The historian Ronald Binns calls the idea that the area had been isolated until then the myth of the lonely loch; the road made sightings easier to report, but the monster was largely made by the newspapers.

The Surgeon's Photograph

In 1934 the Daily Mail published the most famous image of the monster: a long neck and small head rising from the water. It was attributed to a respected London doctor, Robert Kenneth Wilson, which is why it became known as the Surgeon's Photograph. For decades it was the strongest piece of evidence the monster had.

It was a fake. Christian Spurling, the stepson of the big-game hunter M. A. Wetherell, admitted before his death in the 1990s that the creature was a toy submarine fitted with a head and neck made of wood putty. The story became public in 1994, and since then almost everyone has accepted the photograph as a hoax. For more fakes that fooled the world, see famous hoax photos.

Sonar sweeps

Later searches turned to technology. In 1987 Operation Deepscan sent 24 boats in a line along the loch, sweeping it with echo-sounding equipment. It picked up an unidentified contact at a depth of about 180 metres near Urquhart Bay, which made headlines.

The naturalist Adrian Shine, who has studied the loch for decades, suggested the returns might have been seals or other ordinary objects. As with many sonar contacts, the result was intriguing without being evidence of anything unknown.

What the DNA says

The most thorough test so far came in June 2018, when a team led by the geneticist Neil Gemmell of the University of Otago collected water samples from around the loch and analysed the environmental DNA that living things shed into the water. The results were published in 2019.

They found no DNA from large fish such as sharks, sturgeons or catfish, and no DNA from otters or seals. They did find a great deal of eel DNA. Many scientists now think large eels may explain a good share of the sightings, although nobody has shown that eels in the loch grow to unusual sizes.

How a DNA survey works

Environmental DNA, often shortened to eDNA, is one of the most useful tools in modern ecology. Every living thing sheds traces of its genetic material into its surroundings, in skin, scales, mucus and waste. By filtering water samples and sequencing the DNA they contain, scientists can build a list of what lives in a lake without needing to see or catch anything.

That makes it a powerful test for the Loch Ness legend. A population of large animals would leave genetic traces, and the 2018 survey sampled the loch at different places and depths. The method cannot rule out every possibility, but it found no trace of the reptiles, large fish or marine mammals proposed over the years, which is about as close to a direct answer as the search has ever come.

Why the legend survives

The Loch Ness story has everything a lasting legend needs: a vast, dark, deep body of water, sightings that are hard to check, a famous photograph and a tourist industry with every reason to keep it alive. Exposing the photograph and testing the water have not ended it, because the legend never depended on evidence in the first place.

The habits that exposed the Surgeon's Photograph are the same ones used on any suspicious image; our guide on how experts check if an old photo is fake explains them, and the story of the Cottingley fairies shows how a hoax can fool even famous believers.