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A team of scientists are to reveal the "plausible theory" they have identified for sightings of Nessie.

Research led by a New Zealand university has sought to catalogue all living life in Loch Ness by analysing DNA collected from water samples.

Last month, the team said it had a biological explanation for the Loch Ness Monster.

This along with other findings from the study are to be announced at an event in Drumnadrochit later on Thursday.

More than 200 water samples were taken at various depths throughout the loch last year, collecting all forms of environmental DNA (eDNA) for further analysis.

The eDNA was extracted and sequenced, resulting in about 500 million sequences and these were checked against existing databases.

The work led by New Zealand's University of Otago was done to record all current life in Loch Ness, including plants, insects, fish and mammals.

The Loch Ness Monster is one of Scotland's oldest and most enduring myths. It inspires books, TV shows and films, and sustains a major tourism industry around its home.

The story of the monster can be traced back 1,500 years when Irish missionary St Columba is said to have encountered a beast in the River Ness in 565AD.

Later, in the 1930s, The Inverness Courier reported the first modern sighting of Nessie.

In 1933, the newspaper's Fort Augustus correspondent, Alec Campbell, reported a sighting by Aldie Mackay of what she believed to be Nessie.

Mr Campbell's report described a whale-like creature and the loch's water "cascading and churning".

The editor at the time, Evan Barron, suggested the beast be described as a "monster", kick starting the modern myth of the Loch Ness Monster.

Gary Campbell, keeper of a register of Nessie sightings, receives on average 10 reports a year of something unexplained being spotted in the loch's waters.

Given that more than 400,000 people visit Loch Ness every year, Mr Campbell said seeing something was "pretty rare".

But he has long believed that eventually science will reveal a cause for the sightings.

Explanations for the monster offered in the past include it being swimming circus elephants.

In his research of Nessie, Glasgow-based palaeontologist Neil Clark found fairs and circuses were a common occurrence in the Inverness area, particularly from the early 1930s.

He said elephants may have been allowed to swim in the loch while the travelling carnivals stopped to give the animals a rest.

Another theory is that large fallen branches floating in the loch are the cause of monster sightings,