What does Nessie like to eat?

Existence has not yet been proven, so we don't know.

People fishing for Nessie, the famous monster of Loch Ness, often bait their hooks with (store bought) haggis. This is done to imitate the critter's natural food, the Great Highland free-roaming haggis. Nessie captures and eats these rare creatures when they slip off the sloped banks of the Loch. When they enter the water, as they have evolved with the legs on the left or right side of their body longer than the other side to assist them in walking on mountain sides, they can only swim in circles. They rapidly tire becoming easy prey for the monster.

A rarely known fact about Nessie's eating habits is that she is unable to fully digest the skin or fur of the haggis. But, she has adapted, and now will regurgitate these waste products soon after eating one, to avoid the constipation and flatus that occurs if the hide is allowed to travel further down her digestive tract, which causes the haggtose intolerance. Locals of the area regularly scour the vicinity around the lake to find the hairy haggis hides hidden on the banks by the monster. Once these hides are tanned by one of the ancient Highland techniques, they can be used as a cost-effective imitation of the more popular, and more expensive, hide from the famous Nauga, from Naugatuck, Connecticut (Naugahyde), sometimes in upholstery work. But, owing to the hide's size and shape, it is used more often to create the bladder for the beloved Great Highland Bagpipe.

An aside note: There have been reports over the centuries of the sound of distant bagpipes coming from the lake. Some people attribute these musical notes to Nessie's haggtose intolerance-induced flatus, but no one has been able to verify that as the source of the sounds as yet. The bagpipe itself, with the use of the haggis hide, may
have been developed to imitate those sounds of Nessie echoing over the Loch.

We do off course , at Scottish Myths and Legends Limited [ S.M.A.L.L] receive tripe like this daily. The truth is that Nessie eats tourists proved by the fact that so few people are around to say they have seen her. Locals do not fall into her clutches as her feeding times are the same as the pub opening hours, why do you think they were set as they are? Have you ever seen a Scotsman on the lochside with a camera during opening hours. I rest my case.