Birds in southern Öresund in relation to the wind farm at ... - Vattenfall

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Table. 4. Overall Jacob’s indices for the wind farm area and the adjacent buffer zone (up to 2 km from the wind farm, excluding the wind farm area (see Fig. 7) for the five regularly occurring species for aerial and boat surveys respectively. Negative indices indicate avoidance of the area in question, positive ones preference. Indices close to zero shows that the area is used roughly in proportion to the size of the area (see methods for more details about the Jacob’s index). Genomsnittliga Jacobs index (D) för själva Lillgrund och intilliggande områden (en zon på 2 km från de yttre turbinerna, se Fig. 7) för de fem talrikaste arterna baserat på flyg- och båtinventeringar före och efter etablering av vindkraftparken på Lillgrund. Negativa indexvärden visar på undvikande av området i fråga. Positiva indexvärden på preferens för området i fråga. Värden nära noll visar på att området utnyttjas i proportion till hur stort det är (se metoder för mer detaljer om Jacobs index). Species Sub-area Aerial surveys Boat surveys PrePostPrePostconstructionconstructionconstructionconstruction Cormorant Wind farm - 0.49 -0.84 -0.79 -0.69 2 km Buffer zone -0.52 0.82 - 0.71 0.14 Long-tailed Wind farm -0.23 -0.85 0.48 -0.14 Duck 2 km Buffer zone 0.06 -0.41 0.78 0.77 Eider Wind farm 0.06 0.08 0.80 -0.09 2 km Buffer zone 0.79 0.62 0.68 0.11 Red-breasted Wind farm -0.26 -0.42 0.41 -0.27 Merganser 2 km Buffer zone 0.22 0.07 0.47 0.03 Herring Gull Wind farm -0.36 0.03 -0.11 -0.71 2 km Buffer zone 0.06 -0.27 -0.20 0.46
Cormorant Phalacrocorax carbo As is apparent from Fig. 8, the number of Cormorants counted during the aerial surveys varies markedly between different surveys. Large flocks fish in the southern part of Öresund, using Pepparholm and Saltholm for roosting, the total number of birds amounting to several thousand at occasions (Bengtsson 1999, 2000). We have not seen these large flocks at the aerial surveys in southern Öresund but large flocks have been seen (in a distance and outside survey lines) during earlier boat counts (Green & Nilsson 2006, Nilsson & Green 2009). Before the construction of the wind farm Cormorants in smaller groups were regularly found on Lillgrund. Cormorants were still observed there in the post-construction period but numbers in the wind farm were smaller than before (Fig. 11). Densities of Cormorants in the three different zones around the windfarm are shown in Fig. 12. During the three surveys pre-construction, the mean densities were very similar in all three zones, whereas Cormorants were hardly observed during the aerial surveys postconstruction. Two values in Fig.12 deviate markedly from the others, both in the buffer zones, being related to observations of flocks. In general density calculations for the Cormorant are much dependent on the occurrence of larger flocks. The occurrence of fish shoals will lead to large concentrations of Cormorants on some occasions ( see above) but this did not occur at the aerial surveys. The number of birds counted during the surveys in the different zones is seen in Table A10 in the appendix. During the surveys in 2006 (before) a mean total of three cormorants was found at the surveys within the coming windfarm area, whereas the only Cormorants noted within the windfarm after establishment were found in 2009, when a total of four individuals were counted during the four surveys undertaken that winter. Mean totals for the buffer zone varied between 0 and 62, whereas the mean counts for the outer zone varied between 8 and 108 (Table A10). Too few observations were obtained during spring for a meaningful calculation of densities. 29
Page 1 and 2: Birds in southern Öresund in relat
Page 3 and 4: Contents Summary 4 Svensk sammanfat
Page 5 and 6: the birds and/or the flocks, the be
Page 7 and 8: Metoder Inventeringarna av rastande
Page 9 and 10: Alfågel (Fig. 14-19) Alfågeln öv
Page 11 and 12: Liksom vid andra inventeringar av r
Page 13 and 14: Introduction Southern Öresund is a
Page 15 and 16: Lillgrund is situated in the southe
Page 17 and 18: had to be made with only one observ
Page 19 and 20: Fig. 5. Map of the southern part of
Page 21 and 22: Fig. 6 . Map over the wind farm at
Page 23 and 24: transect was divided into 10 km lon
Page 25 and 26: Results Staging and wintering birds
Page 27: Table.3 Percentage of the total num
Page 31 and 32: Fig. 10. Summary distribution maps
Page 33 and 34: Overall Jacob’s index (D) for the
Page 35 and 36: Long-tailed Duck Clangula hyemalis
Page 37 and 38: ehind the large variation is that f
Page 41 and 42: Common Eider Somateria mollissima T
Page 47 and 48: Jacobs Index Jacobs Index 1 0,5 0 -
Page 49 and 50: 2500 2000 1500 1000 500 0 MIN MEAN
Page 51 and 52: Fig. 30. Details of Fig. 29 to show
Page 53 and 54: large-scale changes in abundance ar
Page 55 and 56: 600 500 400 300 200 100 0 MIN MEAN
Page 59 and 60: Jacobs Index Jacobs Index 1 0,5 0 -
Page 61 and 62: Lillgrund and the wind farm are sit
Page 63 and 64: The spring migration season, and he
Page 65 and 66: % of all echoes (flocks) 45 40 35 3
Page 71 and 72: irds given the assumptions used abo
Page 73 and 74: % of all echoes (flocks) % of all e
Page 75 and 76: % av alla ekon (flockar) 20 15 10 5
Page 77 and 78: species, some species being better
Page 79 and 80:
area and from a Dutch farm show tha
Page 81 and 82:
distance from the farm, although mo
Page 83 and 84:
Literature Alerstam, T. 1972. Noctu
Page 85:
Petersen, I. K. & Fox A. D. 2007. C
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Birds in southern Öresund in relation to the wind farm at ... - Vattenfall

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