The Millennium Atlas of Butterflies in Britain and Ireland


  • Johan Olausson

The Millennium Atlas of Butterflies in Britain and Ireland by Jim Asher, Martin Warren, Richard Fox, Paul Harding, Gail Jeffcoate & Stephen Jeffcoate . Oxford : Oxford University Press , 2001 . 456 pp . Hardback . ISBN-13 978 0198505655 .

This atlas presents the results of Butterflies for the New Millennium, the most comprehensive survey of butterflies ever made in Britain and Ireland. The study, carried out between 1995 and 1999, was organised by Butterfly Conservation, the Centre for Ecology and Hydrology and the Dublin Field Naturalists’ Club, and involved thousands of volunteers, making recordings all across the British Isles. This excellent reference book provides the latest development and trends of our butterflies, the habitat they live in, the threats they face, and the major changes that have occurred since the previous publication of such an atlas in 1984.

The book begins by giving a short background of butterfly conservation in Britain and Ireland, and summarizes important personalties and projects, which have led up to the Millennium Atlas. It then moves on to describing the various butterfly habitats, and also gives an account of the great variety of geology, soil and climate that occur in such a relatively small area as Britain and Ireland. The major habitats are shaped by these characteristics, and widely influences the distribution of butterflies. Furthermore, two chapters are dedicated to explain how data was recorded, and how it was then interpreted. The main results of the five year long survey make up the core of the atlas, which consists of distribution maps and detailed accounts of each butterfly species, accompanied by beautiful photographs. For over two hundred pages, the reader may engross in foodplants, life cycles and colony structures, flight periods, abundance, trends and outlooks for all of Britain’s and Ireland’s butterfly species; enough to make any lepidopterist, amateur or professional alike, more than satisfied. However, in spite of pictures and descriptions, the atlas is not designed to be a field guide, this is covered well by other books.

This wealth of background information puts the Butterflies for the New Millennium survey in context, explaining its methodology, as well as discussing the results and their implications. The overall distributions of butterflies in Britain and Ireland have undergone rapid changes during the last 200 years since the start of butterfly monitoring, with the overall picture being rather gloomy. While 15 species have increased their range expansion, another 29 (half the British total) is in decline, and five species completely extinct. Most constrained are, not surprisingly, many of the habitat specialists, as main causes of decline are habitat loss, changing habitat management, habitat fragmentation together with intensified agricultural practice, chemicals and pollution.

Overall, the book provides a fantastic work of reference to anyone with interest in the current trends and conservation of butterflies. Conserving butterflies is a large and difficult task, but as the book very nicely puts it, we have never been better equipped to face the daunting challenge.