Crayfish found at Ballachulish Quarry in Lochaber
North American signal crayfish have been found in a pond at Ballachulish - the most northerly recording of the invasive species in the west Highlands.
A Highland Council ranger made the find at a quarry.
The crayfish have been blamed for feasting on native insects, frogs and small fish in the River Clyde and in lochs in Dumfries and Galloway.
The most northerly recordings of the species were made in the River Nairn in the Highlands.
Highland Council, Scottish Natural Heritage and the Lochaber Fisheries Trust are discussing what action to take to control the crayfish.