They Used DNA, Sonar and Underwater Robots. Loch Ness Still Won’t Give Up Its Monster

Deep beneath the dark waters of Loch Ness, a sonar operator watched something unusual appear on his screen.

The instrument had detected a large object roughly 171 metres below the surface. The reading was strong enough to attract the attention of researchers searching the loch.

They sent another vessel to investigate, hoping to discover what had caused the signal. By the time it arrived, the mysterious object was gone. The encounter happened during Operation Deepscan in 1987, one of the most ambitious attempts ever made to discover what might be living in Scotland’s most famous lake.

Nineteen Boats Search for Nessie

In October 1987, researcher Adrian Shine helped organize an enormous search of Loch Ness. Nineteen boats equipped with sonar instruments formed a line across the water.

The vessels moved together, sending sound waves into the depths and collecting information about objects beneath them. Their arrangement created something like an underwater wall of sound, allowing researchers to examine large sections of the loch.

The operation attracted international attention, with television crews and reporters following the search. For the people involved, it was an opportunity to investigate the legend using equipment far more advanced than anything available to earlier monster hunters.

Most readings could eventually be connected with stationary objects. But three deeper sonar contacts proved more interesting, particularly because follow-up boats couldn’t relocate them.

One especially strong contact had appeared at approximately 171 metres. Whatever had produced that reading was never identified.

A Lake With Plenty of Places to Hide

Loch Ness stretches approximately 23 miles through the Scottish Highlands. Its water is unusually dark because peat carried down from the surrounding countryside reduces visibility.

Even on a bright day, looking beneath the surface is difficult. In places, the loch reaches depths of more than 200 metres.

The bottom contains steep slopes and deep basins where equipment must operate in darkness. Exploring such an enormous volume of water requires patience, powerful instruments and a great deal of time.

These conditions have long fascinated people interested in the Loch Ness Monster. Witnesses have described unusual wakes, dark shapes and long necks rising above the surface. Some accounts involve only a fleeting glimpse, while others describe something moving through the water for several minutes.

The variety of sightings has helped keep the legend alive through generations.

Scientists Begin Collecting DNA

In 2018, geneticist Neil Gemmell from the University of Otago arrived at Loch Ness with a different approach to the mystery. Instead of searching for an animal with cameras or sonar, his team wanted to examine genetic material left behind in the water.

Every living creature releases biological traces into its surroundings. Skin cells, mucus and other tiny particles contain DNA that scientists can collect and study.

This technique is called environmental DNA, or eDNA. It allows researchers to identify animals without having to see or capture them.

Gemmell’s team collected 250 water samples from locations around Loch Ness, including areas near the surface and deeper sections. The researchers hoped to learn more about the creatures inhabiting the loch, including animals that rarely appeared in photographs or direct observations.

An Interesting Discovery in the DNA

When the findings were announced in 2019, one result attracted particular attention. Eel DNA appeared in samples from almost every location tested. European eels were already known to inhabit Loch Ness, but their widespread presence sparked renewed interest in an unusual possibility.

Could some of the famous sightings involve an exceptionally large eel?

Eels have elongated bodies and move through the water in a distinctive way. A large individual briefly appearing near the surface could be an extraordinary sight. Gemmell explained that the genetic testing could identify eels but couldn’t establish the size of individual animals.

The study also revealed information about many other species living in the water. Researchers were building a clearer picture of an environment that had inspired mysterious stories for generations.

Underwater Robots Join the Hunt

Over the decades, researchers have introduced increasingly sophisticated equipment into Loch Ness. Sonar systems can examine areas beyond the reach of ordinary cameras, while underwater microphones allow investigators to listen for activity beneath the surface.

Remotely operated vehicles offer another advantage. They can descend into deep water carrying lights and cameras, exploring places that would be difficult for human divers to reach. In May 2025, an expedition known as The Quest deployed underwater robots and baited cameras to investigate the loch.

The equipment recorded fish, including pike and salmon. But the researchers also made an unexpected discovery connected with the history of monster hunting.

They recovered old cabling associated with equipment used by researcher Robert Rines during his investigations in the 1970s. Rines had been one of the most famous scientific investigators of Loch Ness. His expeditions produced underwater photographs and sonar readings that attracted considerable attention at the time.

Half a century later, modern explorers were recovering physical traces of those earlier searches.

Strange Sounds Beneath the Water

Loch Ness investigators have also used hydrophones, sensitive microphones designed to detect sound underwater. These instruments can pick up noises traveling through the depths, including activity that might occur far from the listening equipment.

During recent investigations, teams have reported unusual underwater sounds that attracted further interest. Water carries sound differently from air, sometimes allowing noises to travel considerable distances. Identifying the precise source can be difficult when an event happens somewhere in a vast, dark lake.

Researchers can compare recordings, examine their timing and look for patterns that might help determine what produced them. For people fascinated by Nessie, the possibility of detecting something through sound offers another way to investigate encounters that happen beyond human sight.

The Sightings That Started It All

The modern Loch Ness Monster legend became internationally famous during the 1930s, when reports of unusual creatures began attracting widespread newspaper attention. Witnesses described unfamiliar shapes moving through the water, sometimes with long necks or large bodies appearing briefly above the surface. The stories brought curious travelers, photographers and investigators to the Scottish Highlands.

Some people spent hours watching the water, hoping to witness something extraordinary. Others organized expeditions using boats, cameras and equipment designed to search below the surface. The encounters inspired books, films and scientific investigations, making Nessie one of the world’s most recognizable mysterious creatures.

One of the earliest famous photographs appeared in 1933, when Hugh Gray captured an unusual shape in the water. The image became part of the growing collection of material examined by people searching for the monster.

As more witnesses came forward, the legend expanded far beyond Scotland. Loch Ness became a destination for anyone fascinated by creatures that might remain hidden in remote places.

New Eyes on the Loch

The technology available to modern explorers continues to improve. Powerful underwater cameras, advanced sonar systems and genetic sampling give researchers opportunities that earlier generations couldn’t have imagined.

Each expedition can examine previously unexplored areas or revisit locations associated with older encounters. Some researchers concentrate on the biology of the loch, while others focus on unusual observations that deserve closer examination.

New equipment may eventually capture something that earlier searches missed.

Until then, the investigations continue to attract people who believe there’s more waiting beneath the surface.