Övervakning av fåglarnas populationsutveckling. Årsrapport för 2010.

We present the results of the Swedish Bird Survey, run by the Department of Biology, Lund University, as a part of the National Monitoring Programme of the Swedish Environmental Protection Agency. The results for 2010 include data from 622 winter point count routes in 2009/2010 (35th winter), of which 281 were carried out during the Christmas/New Year count and 262 summer point count routes (36th year). A third programme is running since 1996 with 716 Fixed routes, systematically (semi-randomly) distributed over Sweden (combined line transect and point counts). In total 498 Fixed routes were completed in the summer of 2010 (third best year). Trends were analyzed using TRIM. A new programme for covering night-active birds started in 2010 (point counts along roads with one route per 25x25 km square of the country). 105 routes were covered at three occasions each (March, April and June) this year. In the Christmas/New Year count 2009/2010, about 300,000 individuals of 133 species were counted by 230 observers on 281 different routes (Fig. 1). Almost half of the birds were Bramblings. Moderate to strong increases in winter populations over the last decade are present in eleven species. Declines over the same period are prominent in four species (Fig. 10). On the point count routes in summer 2010, about 100 000 birds of 204 species were counted by 161 observers on 262 different routes (Fig. 1). From the Fixed routes 143,000 birds of 221 species were reported by 250 different persons. Trend graphs for a large number of species are presented in Fig. 11. More graphs and indices can be found on the homepage (address below). Over the last 10–12 years, 22 species have had moderate to strong positive trends, while 18 species show clear negative trends during the same period. Following the hard winter of 2009/2010, the summer population size of cold sensitive species like Grey Heron, Wren and Goldcrest dropped dramatically from the year before. The night routes yielded good data for five owl species and several other night-active birds. In the future we expect to be able to calculate trends for at least ten species that none of the other programmes have covered before. Larger mammals were also counted on the night routes, suggesting that it will be possible to calculate trends for about ten species. Bird indicators were calculated for Sweden based on summer point counts and the species selection and methods of the Pan-European Common Bird Monitoring Scheme (page 10). Farmland birds (“Vanliga jordbruksfåglar”, 11 species) show a more than 50% decline since 1975. Woodland birds (“Vanliga skogsfåglar”, 26 species) have declined with about 30%, whereas a group of other common birds (“Övriga vanliga fåglar”, 21 species) have declined with about 10%. We also present the corresponding indicators based on the new system with Fixed routes (indices since 1998). All but one of six indicators turned downwards during 2010. The birds in Sweden are doing relatively better according to the Fixed routes, but also among them, farmland birds are doing worst. Another set of indicators, official indicators of biodiversity within the national Environmental Objectives set by the Swedish Parliament based on data from the Fixed routes, are presented as well. Four indicators showed positive changes between 2009 and 2010 (farmland, mountain tundra, mountain birch forest and northern wetlands) while two indicators remained virtually unchanged between the years (forest and ‘a rich diversity of plant and animal life’). The indicators for birds in lakes and streams and for southern wetlands showed lower values 2010 compared to 2009.