Vol. 27: 193–206, 2015 ENDANGERED SPECIES RESEARCH Published online April 29 doi: 10.3354/esr00656 Endang Species Res OPENPEN ACCESSCCESS Is research effort associated with the conservation status of European bird species? H. J. Murray1, E. J. Green1, D. R. Williams1, I. J. Burfield2, M. de L. Brooke1,* 1Department of Zoology, Downing Street, Cambridge CB2 3EJ, UK 2BirdLife International, Wellbrook Court, Girton Road, Cambridge CB3 0NA, UK ABSTRACT: Research effort is critical to the success of interventions which aim to reduce de - clines in biodiversity and so can be considered as a conservation resource. European bird spe- cies are among the best studied and most popular groups of animals, yet 1 in 10 are currently globally threatened or near threatened, and many have been prioritised by various multilateral environmental agreements. To investigate how research effort is directed towards European bird species, and in particular whether conservation listing prompts additional research, the number of outputs from a Web of Science search related to conservation was used to develop an index of research effort for each species. This index was then analysed against a set of popula- tion, morphological, ecological and socioeconomic parameters collated from the literature, plus measures of threat level. A series of generalised linear models revealed that the most important factors in explaining the distribution of research effort amongst European bird species included ‘European population size’, ‘potential research investment’ and ‘habitat type’, which were linked to ease of study. Also important were the species’ generation length, 1990−2000 European pop- ulation trend and migration status. Research effort was not well targeted with respect to either European or global threat status, and there was little support for the suggestion that inclusion of species in legislative instruments such as Annex I of the EU Birds Directive might stimulate research. Research effort must become better prioritised to achieve the greatest net conservation benefit. KEY WORDS: EU Birds Directive · IUCN Red List · Threatened birds · Web of Science INTRODUCTION are currently listed as globally threatened or near threatened (IUCN 2012). Across the world, biodiversity is in decline and the The most effective conservation strategies vary ecological impact of humanity is increasing (WWF between species due to ecological, physiological and 2012). In response, governments and other organisa- socioeconomic differences. This means research in tions are taking conservation action to prevent spe- this field cannot necessarily be transferred between cies extinction. This is particularly true of birds, one species and that species-specific studies may be of the best studied and most popular groups of ani- needed, especially since the success of conservation mals; nonetheless, many species are still undergoing actions is maximised when they are based upon sci- serious declines (BirdLife International 2013). Glob- entific evidence (Sutherland et al. 2004, Williams et ally, avian extinction rates are expected to reach 1.5 al. 2012). species per 1000 species per year by the end of the Unfortunately, there are insufficient resources to century (Pimm et al. 2006), and in Europe 44 species carry out all the work necessary to halt declines in © The authors 2015. Open Access under Creative Commons by *Corresponding author: [email protected] Attribution Licence. Use, distribution and reproduction are un - restricted. Authors and original publication must be credited. Publisher: Inter-Research · www.int-res.com 194 Endang Species Res 27: 193–206, 2015 biodiversity, and conservation action must be di - METHODS rected to where it can have the greatest impact (e.g. Wilson et al. 2006, Marris 2007). Often the most Data sources of candidate variables. For each spe- threatened species are prioritised (Rodrigues et al. cies, information on a number of parameters was col- 2006), and improving monitoring and research is one lated from the literature alongside details of threat measure, among several types of intervention, which status and inclusion in multilateral environmental can be taken to help reduce species’ risk of extinc- agreements (MEAs). Much of the information is tion. We would therefore expect research effort to be taken from the publication Birds in Europe 2 (BiE2) correlated with threat status of species. (BirdLife International 2004), the most up-to-date Knowledge gap analysis of research effort is a rel- authoritative source on European bird populations. atively new area of conservation science, but, since Field data for this publication were originally col- 2005, several papers have assessed whether research lected in each country by a range of experts, monitor- effort is associated with species’ threat status. Two ing organisations and other regional contributors in papers focussing on bird species concluded that approximately the year 2000. Therefore, where pos- threat status was either significantly associated with sible, data from 2000 were used for candidate vari- research effort (Brooks et al. 2008) or showed a clear ables from other sources. For the present purposes, trend (de Lima et al. 2011). Both analyses found that Europe extends from Greenland, Iceland and Ireland species classed in more globally threatened IUCN in the west across continental Europe and western Red List categories received greater research effort Russia as far east as the Urals and south-east to than those in less threatened groups. In contrast, Cyprus, Turkey, Armenia and Azerbaijan. work on other taxonomic groups, such as Felidae European population size (breeding pairs). The (Brodie 2009) and coral reefs (Fisher et al. 2011), did geometric mean of minimum and maximum Euro- not show a relationship between research effort and pean population size estimates from BiE2 was calcu- threat status. lated for each species; values ranged from 3 (brown Our study first investigates relationships between a fish owl Ketupa zeylonensis) to 176 635 217 (common series of candidate variables, each potentially relevant chaffinch Fringilla coelebs) breeding pairs. to the conservation of European bird species, and re- Percentage of global population in Europe. Taken search effort. The analysis is then extended by run- from BiE2, these data are expressed categorically. ning a set of models to determine which candidate The categories were <5% of global population breed- variables explain most variation in research effort. ing in Europe (e.g. shikra Accipiter badius), 5−24, Candidate variables included population, morpholog- 25−49, 50−74, 75−94, >95 and 100% (e.g. Zino’s ical, ecological and socioeconomic parameters chosen petrel Pterodroma madeira). to reflect different potential influences upon the dis- 1990−2000 European population trend. In BiE2, tribution of research effort across species. Some vari- species were classed as showing 1 of 8 population ables, such as European threat status, were expected trends: stable, fluctuating, small decline, moderate to have an impact because they identify those species decline, large decline, small increase, moderate in - most in need of conservation action, whereas others, crease and large increase. For clarity and ease of such as body mass, were hypothesised to be important analysis in our study they were grouped together into simply because they influence the ease with which categories of: stable, fluctuating, declining and studies can be carried out. This study advances the increasing. field by including some candidate variables that have Potential research investment. For each species not been analysed by previous authors; for example, this index was calculated based on the percentage of different measures of threat were considered along- the European population in each of the n countries of side global IUCN Red List status. Uniquely, it also Europe (BirdLife unpubl. data) and the per capita uses an index of research effort which takes into ac- gross domestic product (GDP) of these countries count the impact each paper may have upon the sci- (World Bank 2012): entific community by considering the year of publica- tion and the impact factor of the journal. Thus, our Potential research investment = n focus is on factors, especially conservation status, that % of European wintering population in country 0.5 k may influence research effort, a contrast to previous ∑ × per capita GDP of countryk + k (1) studies (e.g. Restani & Marzluff 2002, Male & Bean n 2005) which have investigated how conservation 0.5 % of European breeding population in country k ∑ × per capita GDP of country k funds are distributed among threatened species. k Murray et al.: Research effort on European bird species 195 For this index, based on the anticipation that spe- European birds. Species in Annex I of the Directive cies with a high proportion of their populations in are those in danger of extinction, those which are wealthier countries may be more heavily re searched, rare, vulnerable to specific changes in habitat, or some caveats must be entered: the index assumes which require particular attention due to the specific that 50% of time is spent in breeding areas and 50% nature of their habitat. Member States are obliged to in wintering areas; the data available for the percent- maintain or improve the conservation status of these age of the European population in each country are species by protecting their habitat. For 15 species more accurate for breeding than wintering popula-