BB June 2009 - edit pages 22/5/09 15:47 Page 296 Birds of Conservation Concern 3 The population status of birds in the United Kingdom, Channel Islands and Isle of Man Mark A. Eaton, Andy F. Brown, David G. Noble, Andy J. Musgrove, Richard D. Hearn, Nicholas J. Aebischer, David W. Gibbons, Andy Evans and Richard D. Gregory Arctic Skua Stercorarius parasiticus Alan Harris ABSTRACT This is the fourth major review of the status of birds occurring in the UK, Channel Islands and Isle of Man.We present Red, Amber and Green lists of conservation concern based on assessments using objective listing criteria and using the most recent data.The listing criteria assess global conservation status, historical population decline, recent population decline (numbers and geographical range), European conservation status, rarity, localised distribution, and international importance of populations. Some changes have been made to the criteria since the last assessment, and the effect of these changes is discussed. Of 246 species assessed, 52 (21.1%) have been placed on the Red list, 126 (51.2%) on the Amber list and 68 (27.6%) on the Green list. Eighteen species have moved onto the Red list since the last assessment in 2002, and six have moved from Red to Amber. 296 © British Birds 102 • June 2009 • 296–341 BB June 2009 - edit pages 22/5/09 15:47 Page 297 Birds of Conservation Concern 3 Introduction extinction. Globally, 1,226 of 9,856 (12%) bird This paper presents the third ‘Birds of species are considered to be at risk, whereas in Conservation Concern’ status assessment for Europe 24 of 526 (5%) regularly occurring birds in the UK. We have reviewed the status of species are Globally Threatened and in the UK each regularly occurring species against a set of just two of 246 (less than 1%) are so threatened quantitative criteria in order to place each (BirdLife International 2008a,b). The relative species on one of three lists: ‘Red’, ‘Amber’ or strength of both governmental and non-gov- ‘Green’. By using such a simple ‘traffic light’ ernmental conservation organisations in the system, we can provide a single, easily under- UK has ensured concerted action to prevent stood measure for each species which can be national extinctions in recent decades, and the used to convey concern and hence to help set fortunes of many rare breeding species have priorities for conservation action. been changed for the better. It is widely recognised that current pressures Thus, it is important to identify which upon the global environment are unprece- species are under threat of extinction within the dented, with widespread and severe threats to UK (and we should not be blasé – there are a habitats and the species within them; the great growing number), and which species we have a majority of well-studied species are declining in responsibility to conserve in the global battle distribution, abundance or both (UNEP 2007; against extinction. It is also important that any WWF 2008). The scale of the problems caused exercise designed to set species priorities for by the use of natural resources by humans (such conservation in the UK should consider a wider as climate change, pollution, land degradation range of parameters. The 58% decline in and over-exploitation) at present far exceeds our numbers of Sky Larks Alauda arvensis over the capacity to tackle these problems, although this last four decades equates to a loss of capacity is largely limited by the reluctance of approximately 4 million individuals. Although those with the power to act. Funds for the Sky Lark remains common and is not conservation action are limited, and often the threatened with national extinction, this is first to be lost in times of economic downturn. biodiversity loss on an enormous scale. As a Given an inability to conserve all of the species result, the setting of species priorities in the UK all of the time, prioritising which species should has evolved to recognise such loss. In addition, it receive conservation attention has become a takes accounts of instances where species have well-established part of conservation planning. been depleted owing to pressures in the past, the At a global scale, the IUCN Red Lists of Globally Threatened species highlight those considered most likely to become extinct, by considering measures such as decline in numbers and range (IUCN 2008). Although preventing extinction globally should of ) course be a high pri- ority for conservation programmes, it is important that biodi- rspb-images.com versity loss other than ( extinction is consid- ered. In the UK, and indeed the whole of Sue Tranter Europe, relatively few 157. BoCC2 highlighted the problem of population decline among the UK’s bird species are consid- woodland birds, with eight species on the Red list in 2002. BoCC3 has added four more woodland species to the Red list, among them the Wood Warbler ered to be at risk of Phylloscopus sibilatrix. British Birds 102 • June 2009 • 296–341 297 BB June 2009 - edit pages 22/5/09 15:47 Page 298 Birds of Conservation Concern 3 ) rspb-images.com ( Tom Marshall Tom 158. There is concern that many of the UK’s ‘mountain specialists’ may be adversely affected by warming climate during the coming decades, but, for now at least, the Ptarmigan Lagopus muta remains on the Green list. importance of preserving small and localised (e.g. Aebischer et al. 2000). The next review, populations, and our responsibility to preserve BoCC2, was published in 2002 (Gregory et al. populations that are important on an 2002); the dynamic nature of bird populations international scale. and the pressures and threats upon them means The first formal, quantitative assessment of that regular reviews are sensible, to ensure that the status of the UK’s birds, Batten et al.’s (1990) listings are based upon the latest data and reflect Red Data Book, listed 117 species as ‘demanding current concern. The Red list grew to 40 species care and attention’ in Britain. Although the (nine species moved onto the Red list, whereas criteria used were not identical to those adopted five moved from Red to Amber) and the Amber subsequently for the Birds of Conservation list to 121. This review saw the addition of a Concern (BoCC) assessments, they were similar number of woodland birds (e.g. Lesser Spotted enough that this list of 117 might be considered Woodpecker Dendrocopos minor, Marsh Tit analogous to the Red and Amber lists, and most Poecile palustris and Willow Tit P. montana) to of the 117 have been Red- or Amber-listed by the Red list amid growing concern for declining BoCC reviews subsequently. The first BoCC woodland birds, but recovery in a number of assessment (hereafter BoCC1), published in historically depleted species (e.g. Red Kite 1996 (Gibbons et al. 1996; JNCC 1996), Milvus milvus and Marsh Harrier Circus developed the approach from a single list of aeruginosus) resulted in them moving from the concern to Red, Amber and Green lists, allowing Red to Amber lists. finer distinctions to be drawn and identifying a Since BoCC2, there have been other, shorter, more usable list of species deserving the alternative, reviews of the status of birds in the greatest concern. UK, which has led to the potential for confusion BoCC1 Red-listed 36 species and Amber- between listings. Eaton et al. (2005) explored the listed a further 110. This review was pivotal in use of IUCN guidelines for regional Red-listing the recognition of a number of common and (Gärdenfors et al. 2001) in order to assess the widespread species, most notably those of extinction risk of birds within the UK. They farmland such as Sky Lark, Linnet Carduelis classified 64 species as being regionally cannabina and Corn Bunting Emberiza calandra, threatened, 12 of which were Critically as urgent conservation priorities following Endangered. This list had considerable overlap declines related to agricultural intensification with the Red and Amber lists from BoCC2, 298 British Birds 102 • June 2009 • 296–341 BB June 2009 - edit pages 22/5/09 15:47 Page 299 Birds of Conservation Concern 3 although it was notable that only six of the 12 In this paper, we introduce a new list, the Critically Endangered species were on the third since Batten et al. (1990) – BoCC3 – to BoCC2 Red list. However, the authors concluded replace BoCC2, which is now seven years old. that applying the guidelines of the global Red- This new list will reflect some rapid changes in listing process at a regional scale required a the status of the UK’s birds in the intervening considerable degree of subjectivity (although period. The same general approach has been progress has been made since to improve the used as in previous BoCC assessments, but with guidance, e.g. Miller et al. 2007). In addition, it some minor but important changes to the was felt that the assessment of extinction risk criteria, described below. In a new development, alone could result in a mismatch with likely we also present the results of a parallel conservation priorities in the UK, and stressed assessment at the race level, following the that the prevention of extinction at a regional pioneering work of the UKBAP review. scale does not have to be the sole driver behind conservation action if the future of those species Methods is safeguarded in other regions. Species list A review of birds on the priority list of the The species assessment covered all native species UK Biodiversity Action Plan (UKBAP, see on the British Ornithologists’ Union (BOU) list www.ukbap.org.uk) was conducted in 2005 (Dudley et al.