The current gaps in the archaeological record for early watercraft are a matter of long recognition (Piggott 1982, 7), particularly when compared to other European countries. Chronology is an issue - any surviving remains require to be dated in order to appreciate their significance and to integrate them within the broader context of their contemporary prehistoric society.
There is no recognisable concentration of early watercraft discoveries comparable to those seen in the Humber Basin or on the South Welsh coast. This must be considered surprising, given that Scotland is geographically distinguished by: relatively large size; deeply indented (and hence long) coastline; large areas of estuarine and coastal dunes; vast areas of peat bog (much of it along watercourses); and large numbers of inland lochs and (on occasion) lakes, both deep (glacial) and shallow (periglacial).
The historically-recorded pattern of maritime losses shows relatively few examples from Scottish waters. The RNLI map of published losses for 1876-7 (reproduced in Underwater Archaeology, the NAS Guide to Principles and Practice, 2008) shows their frequency distribution to follow an exponential decline away from the Straits of Dover (notably the Goodwin Sands); Scottish losses are infrequent, and mainly in the major estuaries of the east coast, while Orkney and Shetland are not mapped at all.