The State of Europe's Common Birds 2008 - European Bird Census ...

More documents

Recommendations

Info

The State of Europe’s Common Birds 2008Photo by D. Boucný (birdphoto.cz)Ortolan Bunting Emberiza hortulana is decreasing steeply across much of Europe.IntroductionThis is the third report in a series describing thehealth of common bird populations in Europe,brought together by the Pan-European CommonBird Monitoring Scheme (PECBMS). It presentsthe population trends of 135 bird species, as wellas multi-species indices (indicators), based ondata from 21 annually operated nationalbreeding bird surveys spanning the period from1980 to 2006. With more countries contributingtheir data, and improvements in data qualitycontrol, the results are now more representativeand more precise than before. In fact, thenumber of common terrestrial species that it ispossible to monitor using generic samplingsurveys in the breeding season is probablynearing its maximum. To expand further andproduce relevant European trends and indicesfor more species, PECBMS would need toextend its remit and collate data on rarer species,for example from species-specific surveys.Over the last few years, the indicatorsproduced by PECBMS have been usedincreasingly widely for policy purposes, both atEuropean and national levels, illustrating therelevance of the indicators. The aim is to helppolicy makers understand changes in theenvironment and then make more informeddecisions about the management of naturalresources. Furthermore, the underlyinginformation on individual species trends has itsown value. These data can be used inData | The data are derivedfrom annually operated breeding birdsurveys in 21 European countries,spanning different time periods(see www.ebcc.info/pecbm.html),coordinated through the PECBMS.assessments of species’ conservation status, toexplore the effects of driving forces at differentspatial and temporal scales, and to trigger moredetailed research into the reasons underlyingspecies’ population changes.This report not only presents the latest updateof the wild bird indicators, but also describes theuse of the indicators for policy purposes and forscientific research. It also summarises the stateof knowledge about common bird populationchanges, and indicates the direction of currentand future research.IndicatorsThe latest set of wild bird indicators shows whatis happening to many species that are consideredas common and widespread across Europe. Whilemany rare and localised bird species havebenefited from special protection under the EUBirds Directive and the Natura 2000 network(Donald et al. 2007), many common species havecontinued to decline. Overall, the numbers of allcommon birds declined by around 10% between1980 and 2006 (see Figure 1).4
The State of Europe’s Common Birds 2008Map 1 | Countriescontributing their datato PECBMS.The numbers in parenthesesshow the first year of data provided by eachnational survey: Austria (1998), Belgium (1990),Bulgaria (2004), Czech Republic (1982), Denmark(1976), Estonia (1983), Finland (1975), France(1989), Germany (1989), Hungary (1999),Ireland (1998), Italy (2000), Latvia (1995),Netherlands (1990), Norway (1995), Poland(2000), Portugal (2004), Spain (1996),Sweden (1975), Switzerland (1999),United Kingdom (1966). Data fromthe relatively new scheme inBulgaria, which started in 2004, areincluded for the first time. Moreover, thedata from Estonia now cover a longer timeperiod (1983–2006) and more speciescompared with the previous version (PECBMS2007). Data from Belgium comefrom two regional monitoringschemes in Wallonia andBrussels, covering the period1990–2005; data from thewhole of Belgium areexpected to becomeavailable in the near future.As well as increased geographical coverage,data quality control has been also improved.Data quality is controlled at two main levels:(1) species; and (2) multi-species indices (indicators).(1) To produce a European species index, datashould first be available from countries whichtogether host at least 50% of ‘PECBMS European’population of a species. ‘PECBMS Europe’ includesthose countries which already provide their data, aswell as those which are actively involved in theproject and expect to provide their data by 2010 (forthe full list of the countries, see http://www.ebcc.info/index.php?ID=362). Second, each nationalspecies trend is inspected to confirm whether itreliably reflects real population changes. Thisprocedure involves assessing statisticalcharacteristics, such as slope value and its standarderror, index value and its standard error, and theproportion of each species’ national populationcovered by the monitoring scheme. It alsoinvolves consulting with the coordinators of thenational monitoring schemes (for more details, seehttp://www.ebcc.info/index.php?ID=362).(2) Confidence limits and extent of fluctuations ina species’ index are used to assess whether a speciesshould be included in an indicator. Indices with lowprecision and large fluctuations are examined indetail (for more details, see http://www.ebcc.info/index.php?ID=362).Although stricter criteria have been applied, theresulting indicators are consistent with the previousversions published in 2007, thereby confirming therobustness of the indicators. For more details onmethods, data quality control and speciesclassification, see http://www.ebcc.info/index.php?ID=362 and http://www.ebcc.info/index.p?ID=301.5
Page 1 and 2: The State of Europe’s Common Bird
Page 3: The State of Europe’s Common Bird
Page 11: The State of Europe’s Common Bird

The State of Europe's Common Birds 2008 - European Bird Census ...

You also want an ePaper? Increase the reach of your titles

Delete template?

Save as template?