What is the Loch Ness Monster?

As far back as the 7th Century, people have reported seeing a Loch Ness monster in Scotland. Can science explain these mysterious sightings?

The Loch Ness is a lake in Scotland that holds the largest volume of freshwater in the United Kingdom. But rather than being known for its size, it is famous for the mysterious legend of the Loch Ness monster. For hundreds of years, people have reported catching a glimpse of a huge creature in the lake while others have shared photos they claim to have taken of this sea creature. The legend is so great that even scientists have been intrigued and many have conducted experiments and come up with theories to try and explain what people could be witnessing.

Credit: Heinrich Harder, 1916

 

Painting of plesiosaurs, creatures thought to be most similar to people's descriptions of the Loch Ness monster.

A real creature in Loch Ness?

It has been proposed that Nessie � as the Loch Ness monster is commonly called � could be a prehistoric creature called a plesiosaur, an animal that spanned up to ten meters in length and has long been considered to be extinct. Adrian Shine, the leader of a British team called the Loch Ness Project, has spent over 30 years trying to rationally explain the monster sightings by researching the ecology of the region. If in fact a large creature was living in the lake, there would have to be evidence of a food chain for it to survive. A creature like the Loch Ness monster would most likely eat fish, which in turn would live off large quantities of microscopic animals called zooplankton. There would have to be enough zooplankton in the lake to support populations of larger animals.

A way of estimating the amount of zooplankton in the lake is to examine the quantities of green algae � the bottom rung of the food chain - that zooplankton feed from. Green algae needs some light to thrive, and so by examining how deep down in the lake sunlight can penetrate, researchers can estimate the amount of green algae and following from this, the type of population that could be sustained.