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

More documents

Recommendations

Info

% of all echoes (flocks) 20 15 10 5 0 2002 2005 2008 Year 2009 2010 Fig. 50. The proportion of bird echoes (flocks) passing Lillgrund, 3x3 km covering the wind farm area and its close surroundings, with southerly flight directions in spring during preconstruction (2002 and 2005, filled bars) and post construction (2008, 2009 and 2010, open bars). Andelen fågelekon (flockar) som passerade Lillgrund, 3x3 km innehållande vindkraftparken och dess närmaste omgivningar, under det sydriktade vårsträcket av sjöfåglar åren 2002 och 2005 (före Lillgrundsparken byggdes, grå staplar) och 2008, 2009 och 2010 (efter att parken tagits i bruk, vita staplar). Autumn General The autumn bird migration over southern Öresund passes along a main axis from Northeast towards southwest (Fig. 51). All sorts of birds are involved in the migratory movements in autumn and it is harder to pin-point groups that are more likely to travel at low altitude through the area, than it is in spring. Generally speaking, low-altitude migration is more prevalent in head wind conditions. Depending on general weather conditions and especially wind direction and strength, there are marked differences between different days in where the corridor passes during that specific day. A general concentration effect to the Falsterbo peninsula in the far southwest is usually apparent, as many land birds hesitate to the passage of open water and tries to fly over land for as long as possible. The concentration to Falsterbo is stronger in winds from the western sector and less pronounced in winds from north and east. The overall migration volume in autumn is of course higher than in spring, as all the offspring of the breeding season are migrating at this time of the year in addition to all the adult birds. This means that many millions of individual birds are passing over the southern Öresund area in autumn. Annual totals of registered radar echoes (bird flocks) during analysed days in autumn 2001, 2008 and 2009 varied between just under 9000 to 15 000 (Table A13 in appendix). This probably corresponds to somewhere between 450 000 and 750 000 individual 70
irds given the assumptions used above. Since the number of analysed days in autumn was lower than in spring, the overall migration rate (flocks passing per hour) was about twice as high in autumn compared to spring. Fig. 51. General migration patterns over the southern Öresund in autumn according to radar data from 2001, 2008 and 2009 (yellow arrows show generalised migration directions). Lillgrund with the wind farm is shown by the red square. The transect along which radar echoes (bird flocks) were counted (A-E) is also shown. Generellt flyttningsmönster hos majoriteten av alla fåglar över södra Öresund enligt radarstudier höstarna 2001, 2008 och 2009 (gula pilar anger generella flygriktningar). Lillgrund är markerat med en röd kvadrat. Transekten som användes vid eko (fågelflock) räkning (A-E) visas också. The distribution of autumn migration over southern Öresund during pre- (2001) and post- (2008, 2009) construction of the wind farm at Lillgrund is shown in Fig. 52. As in spring there is variation between years but the concentration to the southern part of the transect (sectors D and E, in contact with the Falsterbo peninsula) is obvious in all years. Sector C with Lillgrund and the wind farm area is passed by a rather modest proportion of the overall migration volume in autumn (13-16 %). A small decrease in the proportion of passing flocks from pre- to post construction years (- 9 %) should be regarded as within the normal variation (Fig. 52). 71 A B C D E
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 and 28: Table.3 Percentage of the total num
Page 29 and 30: Cormorant Phalacrocorax carbo As is
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 67 and 68: % of all echoes (flocks) 20 15 10 5
Page 69: % of all echoes (flocks) 70 60 50 4
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
show all

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

Create successful ePaper yourself

Delete template?

Save as template?