Mackal began investigation into the Loch Ness Monster phenomenon during the 1960s. In 1965, he went to the Scottish Highlands and met several members of the Loch Ness Phenomena Investigation Bureau, who were monitoring the loch in observation vans in hopes of seeing the creature. Fascinated by their work, Mackal began monitoring the waters himself and, after raising $5,000 in America for the Bureau, became the chief scientist for the project, a position he held until 1972, when the Bureau disbanded. During this time, the LNIB conducted sonar probes of the waters near Urquhart Bay and installed underwater strobe cameras with the hopes of providing evidence of the Loch Ness Monster. Mackal also designed a "biopsy harpoon", a dart-like contraption he attached to a submarine in order to collect tissue samples. The team never had an opportunity to use the biopsy harpoons, and were unable to provide any conclusive evidence that the Loch Ness Monster existed. However, Mackal himself was convinced that something lived beneath the waters after recording his own sighting of the creature in 1970, and in his 1976 book The Monsters of Loch Ness, he suggested that a population of large, previously unknown amphibians were living in the loch. Mackal later changed his mind and proposed that the creatures were zeuglodons, serpentine whales believed to have gone extinct several million years ago. Mokele-mbembe During the 1980s, Mackal turned his attention to purported creature, the Mokele-mbembe, which figures such as Young Earth creationists claim is a living dinosaur in the Likouala swamp region of the Republic of Congo. Accompanied by University of Arizona ecologist Richard Greenwell and Congolese biologist Marcellin Agnagna, Mackal undertook two expeditions, the first in 1980 and the second in 1981, to find and photograph the creature. Mackal himself did not actually see the creature, but he and his colleagues did collect multiple firsthand reports from Congo natives, who, according to Mackal, consistently described a creature similar to a long-necked sauropod. During his interviews with the natives, Mackal also heard anecdotes about the Emela-ntouka, another possible living dinosaur which supposedly resembles a Monoclonius or Centrosaurus, the Mbielu-Mbielu-Mbielu, which is said to resemble a Kentrosaurus, and the snake- or lizard-like Nguma-monene. In 1987, Mackal wrote a book about his adventures in the Likouala swamps called A Living Dinosaur? In Search of Mokele-Mbembe. He had tried to obtain funds for a third expedition to the region, but