Rare pouched lampreys spotted migrating up Margaret River

Their description reads like a monster from a horror movie: boneless, bloodsucking, flesh-eating and up to 70 centimetres long.

But seeing a pouched lamprey in the wild is a rare and exciting experience for many people in southern Western Australia.

The ancient eel-like creatures have been seen migrating through waterways in WA's South West, delighting residents who have not seen the fish for years.

Tour guide Sean Blocksidge captured footage at the weekend of pouched lampreys swimming against the current of the Margaret River, about 270 kilometres south of Perth, on a mission to lay eggs upstream.

He said lampreys were once a common sight in the region's rivers.

"If you ever speak to a really old-time local, they will tell you these things came up the river in the thousands," Mr Bloc