The quest for the Loch Ness Monster

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The monster was widely believed to be a 20 to 50ft descendant of the plesiosaurs, marine reptiles that – according to conventional wisdom – had died out with the dinosaurs 65 million years ago. The notion seemed exceedingly unlikely (one expert put the odds at 17 million to one against) but had taken hold during the 1930s, following reports of long-necked, hump-backed creatures in the loch and occasionally on its shores.

In April 1934, London gynaecologist Dr RK Wilson had taken a dramatic photograph of a long, curved neck ending in a small head. Published in newspapers around the world, the ‘Surgeon’s Photograph’ transformed millions into believers in the monster and became one of the most instantly recognisable images of the 20th century.

During the Second World War, the monster kept a low profile but was exploited as a propaganda weapon by both sides. In 1940, the British authorities sent reassurances to Allied prisoners of war that the monster remained in good health, so confounding Axis claims that it had been killed in a German bombing raid.

Interest in the monster surged during the 1950s, with many sightings and photographs, and the publication of Constance Whyte’s More Than a Legend. Whyte catalogued over 80 sightings and concluded that the monster was a plesiosaur that had been protected in the land-locked niche of Loch Ness.

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Whyte’s book came out at a time when public imagination was being fired by pioneering television programmes on natural history, such as Peter Scott’s Look and David Attenborough’s Zoo Quest. These often featured exotic species whose existence had been unsuspected or denied, such as the 60ft whale shark and the Komodo Dragon, a 12ft monitor lizard which Attenborough filmed on a remote Indonesian Island. Lurking in the wings was the coelacanth, a primitive fish that had been pronounced extinct for 60 million years until one was caught alive off the South African coast in 1938. With all this in mind, many accepted that a plesiosaur could have survived in a deep and unexplored Scottish loch with notoriously peat-clouded water.

However, no hard evidence of the monster – bones, a shred of tissue, let alone a live specimen – had ever been collected. The zoological establishment had been highly sceptical from the start, dismissing sightings as optical illusions, hallucinations, hoaxes or misidentified natural phenomena.

Young and headstrong

The Natural History Museum in London took an especially robust anti-monster line. In October 1959, the museum’s trustees issued a memo forbidding all staff from investigating the “Loch Ness phenomenon”. The trustees’ warning was directed mainly at Dr Denys Tucker, the young and headstrong curator of fishes. Tucker, an expert on the migration of eels, was a rising star until an afternoon in March 1959, when he watched a large humped animal swimming in Loch Ness. He decided that the monster was a long-necked plesiosaur, Elasmosaurus – the same species later identified by Tim Dinsdale, an aeronautical engineer whose cine film of a humped object in the loch caused a sensation when it was shown on BBC’s Panorama in June 1960.

Defying the trustees, Tucker began lecturing about “the plesiosaur in Loch Ness” at scientific meetings in London and Cambridge. The trustees included the archbishop of Canterbury, who advised Tucker to renounce his belief in the monster and to “give up eels and turn to God”. When Tucker refused, the trustees sacked him and barred him from the museum. Their decision was upheld despite the intervention of Tucker’s MP and a debate in the House of Commons.

Denys Tucker was not the only professional scientist to lose his job because he pursued the monster. Roy Mackal, assistant professor in biochemistry at Chicago University, was knocked off a promising career after visiting Loch Ness in September 1965. He was bowled over by the Loch Ness Phenomena Investigation Bureau (LNPIB), a military-style operation staffed by dozens of volunteers, united in their determination to find the monster. The LNPIB had been founded in 1961 by David James, MP for Brighton and famous for a daring escape from a German prisoner of war camp, and Peter Scott, the celebrated ornithologist, painter, broadcaster and president of the World Wildlife Fund. The LNPIB’s search strategy included RAF-surplus searchlights, massive photoreconnaissance telephoto lenses, a bright yellow mini-submarine, underwater sonar sweeps and the detonation of gelignite charges to force monsters to the surface.

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When Mackal arrived, the LNPIB had found nothing conclusive and was running out of money. Mackal promptly raised funds in Chicago, was appointed the LNPIB’s scientific director and drew up ‘Operation Bootstrap’, which included biopsy harpoons and a small monster-trap made of chicken wire.

Operation Bootstrap failed, but that didn’t dampen Mackal’s conviction that the monster was a giant amphibian resembling the extinct Eogyrinus. His book, The Monsters of Loch Ness (1976), based around an analysis of almost 400 sightings, cine films and photographs, established him as a world authority in cryptozoology (the study of animals whose existence remains unproven). Chicago University was unimpressed and withdrew Mackal’s academic tenure.

The LNPIB folded in 1972, having obtained no hard evidence of the monster. However, its activities attracted the attention of the Academy of Applied Science (AAS), near Boston. Its president was Robert Rines, a lawyer who had filed patents for high-resolution radar during the war. Also intrigued was Dr Harold ‘Doc’ Edgerton, professor of electronic engineering at MIT and inventor of the ‘strobe’ flash, which had revolutionised underwater photography.

Rines first visited Loch Ness in autumn 1970, armed with sophisticated sonar scanners, an assortment of hormonal attractants and tape recordings of various sea creatures mating. He logged some tantalising sonar contacts, and his determination to find the monster was strengthened the following summer when he and his wife watched a 20ft humped animal ploughing through the water, half a mile offshore.

In August 1972, Rines’ underwater camera (coupled to an Edgerton strobe flash) captured an image even more extraordinary than the ‘Surgeon’s Photograph’. After computer enhancement to remove the ‘fog’ of suspended peat particles, it showed a clean-cut, diamond-shaped flipper, apparently attached to a rough-surfaced body. Various zoological experts stated it to be the right rear appendage of a large, unknown aquatic animal.

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Three years later, Rines’ underwater camera took two more enigmatic photographs that he believed showed the body (drawn out into a long, graceful neck) and bizarre ‘gargoyle’ face of a plesiosaur-like creature.

Rines’ photographs converted Peter Scott into a true believer. Scott also viewed the creature as an icon for his mission to save endangered species. He concocted a formal scientific name for it – Nessiteras rhombopteryx, meaning ‘the wonder from Ness with the diamond-shaped fin’ – and painted Courtship in Loch Ness, a haunting picture of two monsters cruising beneath the surface.

Another convert was Dr David Davies, editor of Nature, the world’s most prestigious scientific journal. On 11 December 1975, Nature carried a paper by Scott and Rines entitled ‘Naming the Loch Ness Monster’ – and Rines’ flipper photograph filled the cover.

Any impression that the scientific establishment was finally taking the monster seriously was short-lived. Irate scientists bombarded Davies’ office with complaints that Nature had debased British science by publishing such nonsense. Just as damning was the revelation that Nessiteras rhombopteryx is an anagram of ‘Monster hoax by Sir Peter S’ – something that Scott always insisted was an unfortunate coincidence.

That was 40 years ago. Since then, serious doubts have been raised about the images taken by Wilson, Macnab, Dinsdale and Rines, while comprehensive sonar sweeps and another 25 AAS expeditions have found no conclusive evidence of the monster.

Could Loch Ness have harboured a large species unknown to science? By autumn 1960, Sir Alister Hardy had reverted to scepticism, but Peter Scott and Roy Mackal remained believers for the rest of their lives. Robert Rines kept his faith until 2008, when his 30th visit to Loch Ness persuaded him that the creatures had been killed off by climate change. And today, a few minutes spent surfing the internet will confirm that opinion is still divided, just as it has been for decades.

Gareth Williams is emeritus professor of medicine at the University of Bristol, and an expert on the history of science.

This article was first published in the December 2015 issue of BBC History Magazine