Mike Lock & Peter Reay, Editors, April 2008

Editorial – extracts

As most of you will already know, 2008 is the first full year of the BTO’s 2007–2011 Bird Atlas project. This is the latest in a series of atlases – The Atlas of Breeding Birds in Britain and Ireland (Sharrock 1976); The Atlas of Wintering Birds in Britain and Ireland (Lack 1986); and The New Atlas of Breeding Birds in Britain and Ireland: 1988–1991 (Gibbons et al., 1993), that have mapped the distribution of the birds of the British Isles by 10-km squares. All these atlases, and those covering many other plant and animal groups, took as their model the Atlas of the British Flora (Perring & Walters 1962). The authors of that ground-breaking book do, however, give a detailed history of ‘dot-mapping’, which had been in existence for almost a hundred years before their work, and was itself innovative in that it attempted to provide country-wide maps of all the organisms within a group.

A most crucial aspect of all such surveys, of course, is that the organisms being mapped should be correctly identified. As an example; hopefully Mark Darlaston’s paper in this issue will help surveyors with the tricky problems of Goshawk identification.

The conclusions that can be drawn from a single mapping exercise are many. In particular, correlations with climatic factors such as mean temperature, and summer maximum temperature can be made and, in the case of plants, with geological and soil factors such as the presence of limestone. The paper in this issue by Helen Booker and Peter Slader shows elegant correlations between three moorland birds and different features of the Dartmoor habitat. Although on a much finer scale than Atlas data, once correlations such as these have been established, it then becomes possible to see how changes to the key factors, such as grazing intensity, can affect bird populations. Once a base line has been established, later surveys can allow us to see and (possibly, sometimes) understand changes in distribution.

Of course, some conspicuous individual species had been counted long before Atlas mapping began, and on a more continuous basis. David Rogers summarises the heronry censuses that have been running in Devon (and nationwide) for almost eighty years and which show intriguing variations in numbers — not always easily explicable.Another long-term study is Peter Goodfellow’s review of the Pied Flycatcher in Devon. This also brings in the importance of ringing to understanding bird ecology, a theme taken up by Vic Tucker’s report on warbler ringing activities at South Milton Ley and Judith Read’s report on the SW Ringers’ Conference. But not even ringing can supply the detailed behavioural observations that come from studying birds at close quarters such as Elaine Hurrell’sWoodpigeon and Peter Ellicott’s Spotted Flycatchers (which also includes a fascinating insight into both birds and young birdwatchers in Devon over 50 years ago).

The 1988–1991 Atlas includes a ‘Change’ map for each species, showing the differences between the 1968–1972 and the 1988–1991 surveys. Sometimes these changes are dramatic — Corncrakes declined by 72% between the two surveys, and Ospreys increased by 580%! Sometimes they are more subtle, and perhaps show the beginning of a greater decline — Skylarks declined by only 3% between the two surveys, and Lapwings by only 13%. We suspect that the new survey will show these last trends maintained and probably accelerated. The distributions of both these species in East Devon are already rather different from those mapped by Sitters (1988).

Other papers in this issue are more general, and we have included a batch of ‘Short Notes’ which give an opportunity to record thoughts and observations. And what do groups in other parts of Devon see on their days out? It’s all here.

We thank Tony John and Nik Ward for acting as independent referees, and Jeremy Hatch for [other] suggestions. This is the first issue produced by Tim Davis and printed by Short Run Press [in Exeter], based on the design framework set up by Ian Farrell and Tim in 2007. Thanks to these, and all contributors including Mike Langman as Art Editor, for a continued high standard of design and production and for helping us to meet our deadlines.

Contents

• Editorial
• The story of Pied Flycatchers breeding in Devon Peter Goodfellow
• The Heronries Census in Devon: 1928–2007 David Rogers
• “Just William” Elaine Hurrell
• That tricky accipiter Mark Darlaston
• The status and distribution of three Dartmoor birds, following a major survey in 2006 Helen Booker & Peter Slader
• The Canary Islands’ special birds Peter Goodfellow
• Aspects of warbler migration and ringing at South Milton Ley Vic Tucker
• The Norfolk Blackbird that winters in Devon – Part 2 Robin & Anne Woods
• My flycatchers Peter Ellicott
• Little Owls Ann Wells
• My best birds Robert Kempster
• South West Ringers’ Conference Judith Read
• Taw & Torridge Branch field meetings July–December 2007 Andy Cudmore
• Book reviews Nick Dymond & Roger Smaldon

Devon Birds
Journal of the Devon Bird Watching & Preservation Society
Volume 61 No. 1 April 2008
ISSN 1753-951X
This issue will be available from 18 April, 2008. £1.95 plus p&p.

• Editors – Mike Lock & Peter Reay
• Art editor – Mike Langman
• Designed by – Tim Davis & Ian Farrell
• Typesetting & production by – Tim Davis
• Printed by – Short Run Press, Exeter
• Published by – Devon Bird Watching & Preservation Society, PO Box 71 Okehampton EX20 1WF
  © DBWPS – Registered Charity 228966