A man who has spent nearly 25 years searching Scotland's Loch Ness for the legendary Loch Ness monster, referred to as "Nessie," believes that it might actually be a giant catfish.

Steve Feltham, 52, the Guiness World Record holder for the longest continuous Nessie vigil, believes that Nessie actually being a catfish is the most probable explanation for the monster's true identity, according to Yahoo! News.

"The current frontrunner is the Wels catfish. It's the most likely explanation," the he told AFP.

Wels catfish - which were introduced to the loch in the 19th century for sport fishing - can grow up to 13 feet long, weigh up to 880 pounds and survive for decades, according to Reuters.

"I have to be honest. I just don't think that Nessie is a prehistoric monster," Feltham told the Times of London. "What a lot of people have reported seeing would fit in with the description of the catfish with its long curved back."

"I'm not saying it's the final explanation. It ticks most of the boxes with sightings - but it doesn't tick them all."

The legend of the Loch Ness Monster dates back to sixth century A.D., when the Irish Monk St. Columba claimed to have banished a "water beast" to the depths of the River Ness, which flows from the northern end of the loch.

Since then there have been a plethora of Nessie "sightings," the most famous one being the black-and-white "Surgeon's Photo" captured in 1934, which later turned out to be hoax.