There's a clever relatively-new way of determining what types of animals are present in a specific area – check the environment for their cast-off DNA, known as environmental DNA (eDNA). Next month, scientists will be using the technique in an effort to prove or disprove the existence of the Loch Ness monster.

eDNA is released as animals excrete bodily waste, slough off their skin, or otherwise shed bits of their genetic material into the environment. Previously, scientists have utilized eDNA analysis to determine the identity of migratory fish, to detect the presence of invasive clams, and to receive early warnings of a frog-killing fungus.

Now, a team from New Zealand's University of Otago is set to analyze the eDNA of everything living in Loch Ness.

Led by Prof. Neil Gemmell, the researchers will use a boat to travel the length of the loch, taking water samples from three different depths as they do so. They will also perform the same process at three other nearby lochs (Garry, Oich and Morar), with those samples serving as controls.

All of the samples will then be sent off to laboratories in Denmark, France, New Zealand, the US and Australia – the sources of the samples will be masked, so the lab techs won't know which samples come from which loch. The eDNA in the samples will subsequently be extracted, sequenced, and then compared to international DNA databases of known species.

If there is indeed a "monster" in Loch Ness, its DNA may show up as a type not found in the other three lochs. This DNA could be from a known species that previously hasn't been verified in Loch Ness, such as a giant catfish, or it could be from a mystery animal that has never had its DNA sequenced before – in the latter case, it should still at least be possible to determine the class of animal that it came from.

"If an exact match can't be found, we can generally figure out where on the tree of life that sequence fits," says Gemmell. "While the prospect of looking for evidence of the Loch Ness monster is the hook to this project, there is an extraordinary amount of new knowledge that we will gain from the work about organisms that inhabit Loch Ness – the UK's largest freshwater body."

The gathering of water samples is scheduled to take place in June, although a definitive analysis of the eDNA isn't expected until next January.