Back when I used to holiday in Colonsay, some fifteen years ago, I had the 48-page booklet ‘The Birds of Colonsay and Oronsay’ as my birding companion. Now this new Atlas has been produced, complete with photos, detailed species accounts and 165 maps of breeding and winter distributions.
The first chapter describes the landscape of the islands, not only in terms of the key habitats they provide for birdlife, but also the geology that led to the formation of the varied terrain. There follows a detailed history of ornithology on the islands, which as well as describing the various surveys that have been conducted on the islands, also includes some fascinating archaeological records, providing insight into the birdlife that might have been present 6,000 years ago.
The species accounts are a detailed narrative (perhaps a little too much so in places), taking the reader through the history of the species on the island, and describing the ecology and any information on dispersal and migratory movements. Accompanying the text are population estimates and distribution and relative abundance maps based on fieldwork conducted as part of the national Bird Atlas 2007-2011, as well as population trends from the BTO/JNCC/RSPB Breeding Bird Survey and other surveys. The addition of distribution and status information at the Scottish and world levels is a nice touch, providing context for the Colonsay and Oronsay population assessments. The inclusion of species with only historical or archaeological records in the main section could be a distraction; I feel these would be better moved to the back, so that the reader can more easily determine which species are currently encountered on the islands.
I found this highly informative book and believe it to be a valuable addition for anyone familiar with the islands.