In Search For The Loch Ness Monster | The Really Wild Show Series 15 | BBC Playback

There have been reports of weird creatures living in Loch Ness for over a thousand years. This seemingly thin loch is actually deceptively big because it's very long and very, very deep. In fact, it holds more water than all the lakes of England and Wales put together. Plenty of places for a monster to hide in. It's a mystery which draws thousands of people here every year. And of course, no mystery would be complete without a fine range of novelty gifts, souvenirs and things to do. I thought I'd do some serious reporting and ask a few folk if they'd actually seen our mysterious monster from the deep. Have you seen the Loch Ness monster? No. No? Has anybody seen the Loch Ness monster? Excuse me, I don't suppose there's any chance you've seen the Loch Ness monster? Yeah, we have. You have seen it? Well, tell me what you saw. Coming down the hill about two years ago in June. Long, dark things in the water. Shapes and shadows and snake-like creatures are pretty popular descriptions. They may sound far-fetched, but this girl is very convinced she saw a long, dark thing in the water. She's not the first to have reported strange movements and shadows. Just under a hundred years ago, the monster sightings began to flow thick and fast after a couple sighted what they described as a long-necked prehistoric creature. This dinosaur monster bore a strong resemblance to a real dinosaur called the plesiosaur, which lived several million years ago. The plesiosaur theory was born. Plesiosaurs were marine reptiles. The classic one that most people know about had a very, very long neck with a fairly small head and fairly slender, quite delicate teeth. It had a barrel-shaped body with four very large flippers and a fairly short pointy tail. It is possible that they went into fresh water to have their babies. They could have been doing that to give birth to live young or they could have been going there like turtles and crocodiles to lay eggs. That is a possibility. So could plesiosaurs have survived all this time? It doesn't look likely. This area was in an ice age only 10,000 years ago and no animal survived that. So any animal living here has to be more recent. On top of that, the plesiosaur was an air-breathing animal. For a large population to a viable population to have been there, you would have been seeing plesiosaurs at the surface breathing every few minutes. Sadly, the Loch Ness phenomenon is not a plesiosaur. But if all these people really believe they've seen something, there really must be some truth there. So what could our Nessie be? Well, there are several very reasonable explanations. The thing about Loch Ness is that it can play some tricks on the old eyes. From the shore, the waves caused by passing boats can look like humps in the water. And if seen in the right light, your monster may be nothing more than the trail of an enthusiastic speedboat driver. That's not all. There are real animals here that can make you think you've seen a monster. For example, the loch and its surrounding shore is prime habitat for otters. And otters may be bigger than you think. Up to one and a quarter metres long, in fact. And when swimming at full speed, they could easily be mistaken for something much larger. As could a seal. Seals from the coast have been known to find their way into the loch. There's an entrance from the sea on the River Ness and salmon and other animals can get in. Seals can stay underwater for minutes at a time and have a habit of sticking their heads up, monster style. Occasionally, a sturgeon can come into the lake looking for a mate. They can grow up to seven metres, swim close to the surface and look like reptiles. They create a large wake and it's easy to see how they might be mistaken for Nessie. The idea of a loch Ness monster is pretty appealing. But at the end of the day, it doesn't seem awfully likely. To give the last word to the scientists, they say there just isn't enough food in the loch to support a monster. There's only about 20 tonnes of fish, which for a large dinosaur-like creature would be like you or me trying to live on a packet of crisps a week. Impossible. So it looks as if Nessie might be all talk and no monster.