Steve Feltham has spent 24 years searching for the Loch Ness Monster.

Steve Feltham, 52, has been searching for the elusive monster, also known to the locals as Nessie, for almost 25 years.

Though some hold to the existence of a plesiosaur-like creature in the lake, Feltham, who moved to Dores beach in 1991 to fulfill his childhood dream, told the Herald Scotland he now believes Nessie to be a very large catfish.

Catfish are native to central and eastern Europe but Feltham believes the Victorians might have introduced them to the deep freshwater lake so they could catch them for sport. “I just don’t think that Nessie is a prehistoric monster”, Feltham was quoted as saying.

Based on biological evidence Steve Feltham – an expert on the Loch Ness Monster, believes that Nessie is actually a catfish.

Instead, he claims Nessie is in fact a Wels catfish – a giant fish that can grow as long as 13ft and up to 62 stone.

The first written record of the monster relates to the Irish monk St Columba, who is fabled to have banished a “water beast” to the depths of the River Ness in the sixth century, long before the introduction of the catfish to the loch.

“I’m in my utopia living here on the shores of the loch”, he said. “We are looking for the last one or two now”.

It is a scaleless fresh and brackish water fish recognizable by its broad, flat head and wide mouth. After careful consideration, the Wels catfish theory seems to fit.

Their wide diet even includes other catfishes.

But it was the famous sighting in 1933, when George Spicer and his wife claimed they saw “a most extraordinary form of animal” which was 4ft high and 25ft long crossing the road near the loch, that started Nessie mania. It was revealed 60 years later to be a hoax that used a sea monster model attached to a toy submarine. They have also been observed lunging out of the water to grab pigeons on land.

Despite the lack of creditable sightings, the loch attracts thousands of tourists annually, and more than a few enthusiastic amateurs who have devoted their life to finding the creature.

“Have I ever regretted my decision?”