Coastguards on the Firth of Clyde were monitoring an unusual visitor to their waters yesterday - a minke whale.

The whale was spotted by a surprised coastguard officer off the north of the Isle of Bute around 1pm. A rare visitor to the Scottish estuary, it was accompanied by a number of dolphins.

Coastguard officers are now monitoring coastal waters to see where the sea mammal heads next.

The whale was first spotted by a group of American children birdwatching near Millport, on Great Cumbrae, accompanied by local coastguard Phil Longsdale.

''There was a big black hump out in the water, which we could see was a minke whale,'' said Mr Longsdale.

The 35ft to 40ft whale was feeding on plankton in the channel between Great Cumbrae and the Isle of Bute.

Sightings of minkes on the Clyde happen at most twice a year, said Mr Longsdale.

Mr Longsdale said: ''The children all had binoculars with them so it was great for them.''