Scotland in the Early Middle Ages to be adopted for house building, often combining layers of stone with turf. Place-name evidence, particularly the use of the prefix "pit", meaning land or a field, suggests that the heaviest areas of Pictish settlement were in modern Fife, Perthshire, Angus, Aberdeen and around the Moray Firth, although later Gaelic migration may have erased some Pictish names from the record. Early Gaelic settlement appears to have been in the regions of the western mainland of Scotland between Cowal and Ardnamurchan, and the adjacent islands, later extending up the West coast in the 8th century. There is place name and archaeological
Firth of Clyde Common and grey seals abound in the firth. Harbour porpoises are also common and while dolphins are much less so, they have been spotted in the upper reaches of the firth in the summer of 2005. Whales do not favour the Clyde and although there have been instances of larger whales beaching themselves or becoming stranded in the upper firth, only smaller pilot or minke whales seem to visit with any kind of regularity. In 2005 the firth was listed as having the 2nd highest incidence of basking shark sightings in Scotland (after The Minch). In particular these huge sharks