Department of Ornithology Polish Academy of Sciences

Transcription

1 Department of Ornithology Polish Academy of Sciences Nadwiślańska 108, Gdańsk 40 tel. (0-58) , fax (0-58) Report on monitoring influence of wind farm in the vicinity of Gnieżdżewo (gmina of Puck, pomorskie voivodeship) on birds. Piotr Zieliński, Andrzej Marchlewski Gdańsk 2007

2 Introduction This report concerns monitoring influence of operating wind farm on birds. It has been prepared upon the order from the company DIPOL Spółka z ograniczoną odpowiedzialnością with seat in Warsaw, ul. Wiertnicza 169. Basic objective was investigating in what way the wind power plant near Gnieżdżewo influences migrating birds, and whether they collide with the turbines. Methods and materials During spring migration birds were counted in several hours periods of observations performed in various weather conditions (table 1). Fields work was performed in the period from to days were spent in field in March, 10 days in April and 5 days in May. At the peak of migration, which is in April, observations were performed once per 3 days. It started early in the morning and lasted for approximately 8 hours. Table 1. Weather conditions during bird watching above Gnieżdżewo in summer Date of Temp. Wind Cloud cover watching ( o C) Rain (km/h) Wind direction (mm/h) Point of observation S cloudless 1, W cloudless SW cloudless SE partly clouded E cloudless E cloudless 3, E cloudless SW overcast 1, W cloudless NW partly clouded 3, NW cloudless NW overcast 1, SE partly clouded W partly clouded W overcast 3, W cloudless E cloudless 1, E partly clouded 3, NW overcast NE cloudless N cloudless NW cloudless S cloudless 3,4 2

3 Quantity of migrating birds in large flocks was estimated by increasing units of measure. According to that method, first, 10 birds were precisely counted, and then the count was done by tens up to 50. The remaining part of the flock was then counted by 50s. Similar method was applied when estimating number of migrant birds, feeding birds and birds resting on fields. In order to check what species may be most exposed to risk of collision with wind turbines, flight altitude above ground level was determined in the following ranges: 1-50 m, m, m and above 150 m. Direction of flight was also noted. Information about weather conditions having significant effect upon the direction and level of flight was obtained from the internet ( The following meteorological data was used: direction and velocity of wind, cloud cover, temperature, precipitation. The data were supplemented by notes taken during field observations. On the basis of obtained maps of location of wind turbines, the whole area was divided into two zones with points of observation situated more or less in the middle of them. Because of the land profile - Płutnica valley necking, vicinity of a forest and predicted direction of migration, observations were mainly performed from one point. In addition to that, information was gathered concerning feeding ground and the method of flying of the Falconiformes that use updrafts to gain height. Type of crop was also noted on which birds fed. Species migrating at night were not counted. All larger migrant flocks and feeding flocks were mapped in the scale 1 : to show direction and intensity of flight, and use of the area as a feeding ground. The area of investigation and location of observation points were not changed comparing to Methods applied in spring 2006 were supplemented by observing behaviour of birds in relation to wind turbines which were performed from several points. The following data were noted, among others: change of flight direction in relation to the turbines from 0º (no change in flight direction) to 180º (maximum change of flight direction); change of flight level. Once or twice a week dead birds were looked for under each turbine. The inspected area had a radius of m. In the event that a dead bird was found, date, species, age and sex of it were noted, as well as distance from the mast, injury and approximate time of collision. To investigate how long dead birds lied under the wind turbines and whether they are removed by predators, the following birds were left under three turbines in the beginning of the field testing: a robin (Erithacus rubecula) that died after a collision with a vehicle, a skylark (Alauda arvensis) and a song thrush (Turdus philomelos). The birds were left on a stubble, ploughed stubble and on a meadow. The robin was most visible of them (the largest 3

4 of the species) and lied on the meadow with his belly facing up; the least visible was the skylark. During each visit, it was checked from a distance whether the left birds were still in the same place. No-one approached them not to leave a smell trace which could lead predatory mammals to the dead birds. Results In spring a total of 8011 birds were seen. Those were individuals observed when flying in a specific direction (migrant) as well as those who stopped by for feeding (feeding birds) of 59 species (table 2). The Lari gulls were most frequently observed. They used the subject area as a place of resting in sea storms and as their feeding ground. All in all, 2,822 gulls of 4 species were identified. The second largest group of birds were passerines (Passeriformes). The area of the farm was used by them for feeding and migrating. Total of 2,289 passerines of 23 species were observed. They flew above at various heights mainly in the east and south-east direction. Nearly 50% of small birds used the investigated area for resting and feeding. Grus grus cranes were also often observed - 1,070 were identified altogether. More than 44% of them fed near the farm, usually in the Płutnica valley, on freshly ploughed fields. No feeding cranes were seen on surface as such. Anseriformes, represented mostly by geese, were seen only while flying. 779 of them were observed altogether, and as far as Falconiformes birds are concerned, 569 were seen. 17% of birds from the last group used the area mostly as a feeding ground during migration. Adult white-tailed eagles (Haliaeetus albicilla) were frequently observed. They nested in the nearby forest and flied above the farm area to their feeding grounds situated at the Puck Bay. They usually flied at very high altitudes. A few eagles were seen flying among the turbines at levels not exceeding 150 m. The use of the wind farm area by birds for feeding purposes is showed on fig. 1. Main feeding grounds of the Falconiformes (of which a common buzzard is the most numerous) were located in the Płutnica valley, which is directly adjacent to the farm. However, cranes fed only in the Płutnica valley. Feeding grounds of other species, including in particular the passerines varied and depended on the degree in which the given areas were then used. 4

5 investigated area crane common buzzard kestrel starling redwing and fieldfare gull Fig. 1. Bird feeding grounds within the investigated area and in the areas adjacent in spring

6 Table 2. Birds identified during spring migration near Gnieżdżewo in Species Birds migrant feeding No. of birds No. of birds PELECANIFORMES PELICANS AND ALLIES Phalacrocorax carbo cormorant 202 CICONIIFORMES STORKS AND ALLIES Ardea cinerea grey heron 7 Ciconia ciconia white stork 31 1 Ciconia nigra black stork 6 ANSERIFORMES WATERFOWL Anser anser greylag goose 2 bean goose + greater whitefronted goose Anser fabalis + Anser albifrons 735 Cygnus olor mute swan 13 Cygnus cygnus whooper swan 20 Tadorna tadorna common shelduck 5 Anas platyrhynchos 4 FALCONIFORMES FALCONS, EAGLES, HAWKS AND ALLIES Accipiter gentilis goshawk 1 3 Accipiter nisus European sparrowhawk 26 2 Aquila pomarina lesser spotted eagle 2 Buteo buteo common buzzard Buteo lagopus rough-legged buzzard 5 1 Circus aeruginosus marsh harrier 12 Circus cyaneus hen harrier 1 1 Circus pygargus montagu s harrier 1 Falco tinnunculus common kestrel 2 7 Haliaeetus albicilla white-tailed eagle 18 Milvus migrans black kite 2 Milvus milvus red kite GRUIFORMES CRANES AND ALLIES Grus grus crane CHARADRIIFORMES GULLS, BUTTON-QUAILS, PLOVERS AND ALLIES Numenius arquata Eurasian curlew 1 1 Numenius phaeopus whimbrel 1 Pluvialis apricaria golden plover 11 Tringa ochropus green sandpiper 1 Vanellus vanellus northern lapwing 19 Gallinago gallinago common snipe 5 herring gull + common gull + Larus argentatus + L. canus + L. ridibundus black-headed gull Larus minutus little gull 15 COLUMBIFORMES DOVES AND PIGEONS 6

7 Birds Species migrant feeding No. of birds No. of birds Columba oenans stock pigeon 17 Columba palumbus wood pigeon 178 PASSERIFORMES PASSERINES Anthus pratensis meadow pipit 48 Bombycilla garrulus Bohemian waxwing 10 Carduelis cannabina linnet 9 40 Carduelis chloris greenfinch 3 Corvus monedula jackdaw 4 Carduelis spinus siskin 2 Emberiza citrinella yellowhammer 15 Emberiza schoeniclus reed bunting 2 Fringilla coelebs chaffinch 7 Lullula arborea woodlark 5 Motacilla alba white wagtail 6 Miliaria calandra corn bunting 2 12 Motacilla flava yellow wagtail 2 Sturnus vulgaris starling Turdus iliacus redwing Turdus philomelos song thrush 14 Turdus pilaris fieldfare Turdus vistivorus mistle thrush 1 Passeriformes sp. passerines unrecognized Corvus corax raven 41 Parus caeruleus blue tit 39 Hirundo rustica barn swallow 7 Parus major great tit 33 Riparia riparia sand martin 2 Total Spring migration of birds observed near Gnieżdżewo was more than 3 times smaller than in spring Weak migration was observed nearly in all species of birds. Migration of passerines was practically noteless; it was 14 times smaller than in the previous year. However, comparing to spring 2006, number of birds feeding and resting within the farm area and its direct vicinity increased. Twice as many feeding birds were observed (almost 45% increase) this year than last spring. Flight level Nearly half of migrant birds flew above the farm at high levels, thus bypassing the potential zone of collision with the turbines. More than 47% of high-flying birds were large species, such as for example, cranes, geese, falconiformes (fig. 2). Small passerines seem more exposed to collision; over 33% of them flew low above the ground, at the level of 50 m (fig. 2). However, falconiformes were observed at various heights. In spring 2006 the air space above the wind farm was used in a similar way by the birds. Large colliding species migrated 7

8 much higher, similar to what happened this year. Also the falconiformes were observed at various heights. Primary difference between the spring 2006 and 2007 was the intensity of flight of passerines. In spring 2006 their flight level was related to weather conditions, including in particular the cloud cover and weak rains. In bad weather (overcast sky, weak wind, showers), the birds flew at the lowest level. Such weather did not virtually occur in spring Long-term highs with cloudless sky prevailed. In such conditions birds migrate at great heights, which makes it impossible to count them. Passeriformes Passerines - wróblowe Grus grus - - żuraw crane Wysokość Height [m] [m] > Wysokość Height [m] [m] > Liczba Number osobników of birds Number Liczba osobników of birds Anseriformes - blaszkodziobe - waterfowl Falconiformes Falconiformes - falcons, eagles, - szponiaste hawks and allies Wysokość Height [m] [m] > Wysokość Height [m] [m] > Liczba Number osobników of birds Liczba Number osobników of birds Wszystkie All species gatunki Wysokość [m] > % 50% 100% Percent Procent of osobników birds Fig. 2. Estimate flight level of the most numerous birds in spring season. 8

9 Influence of wind on migration Basic migration took place in high wind velocity (fig. 3). Especially the larger birds took advantage of the stronger winds that prevailed during spring migration. The least numerous birds migrated during weak wind. In such conditions mainly migration of geese took place. Migration of small birds was most frequent at average wind velocities. Comparing to the migration in spring 2006, this year birds flew in stronger wind. Passeriformes Passerines - wróblowe Falconiformes Falconiformes - falcons, eagles, - szponiaste hawks and allies Number Liczba ptaków of birds >21 Prędkość Wind velocity wiatru (km/h) Number Liczba ptaków of birds >21 Prędkość Wind velocity wiatru (km/h) Grus grus - żuraw crane Wszystkie All species gatunki Number Liczba of ptaków birds >21 Number Liczba ptaków of birds >21 Prędkość Wind velocity wiatru (km/h) Prędkość Wind velocity wiatru (km/h) Fig. 3. Migration of passerines (Passeriformes), falcons, eagles, hawks and allies (Falconiformes), crane Grus grus and all species in relation to wind velocity. Migrant birds - flying in a specific direction at constant altitude were more than 43%. In spring, east, north and south-east migration directions prevailed (fig. 4). The birds flew most numerously in east direction against the wind blowing from that direction. Another direction of flight was towards west. The spring migration towards the west probably relates to local movements. It always occurs in wind blowing from the west or south-west. Also in spring 2006, large number of birds moved west which is in direction opposite to migration. In autumn birds migrated only towards the west and south. 9

10 NW N NE Fig. 4. Direction of flying of all birds above the investigated area in spring Total number of birds observed during migration: N 213, NE 254, E 1643, SE 215, S 384, SW 84, W 721, NW 5. W E SW SE S Behaviour of birds When performing the field work, behaviour of birds was observed and how it was affected by the presence of wind turbines on their route of migration. Various types of behaviour were observed, i.e. change of flight direction, change of flight level and change of formation of a flying flock in case of 165 birds. They constituted 2% of all the observed migrant birds and feeding birds within the investigated area. In majority of cases, change of flight direction was observed in case of medium-sized and large birds. Most frequently behaviour of birds in relation to the wind turbines was observed in the case of the cranes and the falconiformes. Change of flight direction in relation to the originally assumed direction by approximately 45º was observed in the case of 80 birds (48%). One bird changed direction of flight by approx. 90 and then 180. It was also observed that birds bypassed the turbines. Such a situation related to large species which have relatively low maneuverability, such as swans or cranes. Birds changed direction of flight both when they were between turbines and above them, even when they were out of reach of revolving rotors. Flight direction was least frequently changed in front of the turbines when birds were already at the edge of Płutnica valley. Change of flight altitude was observed in the case of 28 birds (33%). It most frequently occurred when birds were between the turbines or directly in front of them. It was also observed that birds flying high above the reach of rotors gained height rapidly. Change of formation of a flying flock was observed only in the case of one flock of cranes. The birds were flying at the height of approximately 150 m and when they flew over the farm 10

11 area, each of them rapidly changed method of flying into more energetic and nervous. Such a nervous behaviour was also observed in the case of one buzzard. Furthermore, it was several times observed that the falconiformes flied very close to operating turbines. They were both migrant and feeding birds. Such behaviour was observed in the case of red kite (Milvus milvus), buzzard, white-tailed eagle and hawk (Accipiter gentiles). Dead birds and bats When performing field work, 3 birds that died as a result of collision with turbines were found, represented by 2 species (table 3) and five bats (table 4). Two goldcrests (Regulus regulus) were found under turbines situated closer to the Płutnica valley, and a skylark (Alauda arvensis) towards the interior of the farm (fig. 5, attachment 1). Three of the five found dead bats were Nathusius' pipistrelles. Species of the other bats could not be identified due to decay resulting from the fact that they had been lying under the turbines for long. All the bats were found under wind turbines situated near the edge of the Płutnica valley, and as much as 3 dead bats were found under one of them (fig. 6). Greater number of collisions under that turbine may be due to the fact that there are some shrubs nearby as well as a small water reservoir at which this bat species willingly feeds. The bats were identified by a chiropterologist - Mateusz Ciechonowski, PhD, from Gdańsk University. On the basis of experiment conducted with dead birds laid under turbines, it may be stated that penetration of predators feeding on carcass under the turbines has little effect upon identifiability of birds that died as a result of collision. A skylark which was laid under turbine no. 6 lied there for 12 days, the song thrush (Turdus philomelos) under turbine no. 4 lied there for 5 days, and the robin (Erithacus rubecula) laid under turbine no. 3 lied there for 5 days. 11

12 Table. 3. Dead birds found under wind turbines near Gnieżdżewo in spring Species Number of birds Wind turbine number Distance from the mast (m) Date Alauda arvensis skylark Regulus regulus goldcrest Regulus regulus goldcrest Table. 4. Dead bats found under wind turbines near Gnieżdżewo in spring Species Numbe r of bats Wind turbine number Distance from the mast (m) Date Pipistrellus nathusii Nathusius' pipistrelle Pipistrellus nathusii Nathusius' pipistrelle Pipistrellus nathusii Nathusius' pipistrelle Bat unrecognized species Bat unrecognized species

13 investigated area wind turbines dead birds Fig. 5. Location of birds that died as a result of collision with wind turbines near Gnieżdżewo in spring Numbers - numbers of wind turbines assumed for the purposes of this report. 13

14 investigated area wind turbines dead bats Fig. 6. Location of bats that died as a result of collision with wind turbines near Gnieżdżewo in spring Numbers - numbers of wind turbines assumed for the purposes of this report. 14

15 Conclusions The following conclusions were drawn as a result of performed observations: 1. area of the farm in Gnieżdżewo is used by birds for transit flights, local flights, feeding and resting; 2. a total of 8,011 birds of 59 species were observed during spring pass-through migration; 3. migration that took place in spring 2007 was 3 times less numerous than the migration in spring 2006 and the pass-through of small passerines was 14 times less numerous; 4. The roam of large colliding species took place on high levels, above 150 m, and small passerines migrated mainly lower - up to 50 m; 5. Falconiformes migrated mainly at high levels. However, more than half of them migrated low, at altitudes up to 150 m. 6. Migrant birds - flying in a specific direction, at constant height - were 43% of the total number, and birds using the farm area for resting and feeding - almost 45%. 7. It was observed that 165 birds changed their flight direction, flight level and formation of flock when confronted with the wind turbines. They constituted 2% of all the observed migrant birds % of birds bypassed turbines by changing their direction of flight by approx. 45. In one case, change of direction by 180 was observed, and some large birds bypassed the farm on a large circle. 9. Change of flight level was observed in the case of 28 birds (33%). 10. It was observed that the falconiformes flied very close to the turbines. Such behaviour was observed in the case of red kite (Milvus milvus), buzzard, white-tailed eagle (Haliaeetus albicilla) and hawk (Accipiter gentiles). 15

16 11. 3 birds that died as a result of collision with wind turbines were found: a skylark (Alauda arvensis) and 2 goldcrests (Regulus regulus). The birds were found under turbines no. 3, 7 and bats that died as a result of collision with wind turbines were found. Three of them were Nathusius' Pipistrelles (Pipistrellus nathusii), and the other two were not recognized. The bats were found under turbines no. 1, 6 (3 individuals) and no. 8. References Åkesson S., Hedenström A., Wind selectivity of migratory flight departures in birds. Behav. Ecol. Sociobiol. 47: Drewitt A., L., Longston R., H., W Assessing the impacts of wind farms on birds. Ibis 148: Fox A., D., Desholm M., Kahlert J., Christensen T., K., etersen I., K Information needs to support environmental impact assessment of the effects of European marine offshore wind farms on birds. Ibis 148: Gromadzki M Analiza kolizyjności lokalizacji farmy wiatrowej w pobliżu wsi Wicko, gmina Wicko, w zakresie awifauny. Maszynopis. Zakład Ornitologii PAN. Gdańsk. Hüppop O., Dierschke J., Exo K-M., Fredrich E., Hill R Bird migration studies and potential collision risk with offshore wind turbines. Ibis 148: Janiszewski T. Włodarczyk R Wpływ planowanych inwestycji elektrowni wiatrowych na awifaunę w obrębie gminy Warta w okolicy zbiornika Jeziorsko. Maszynopis. Towarzystwo Przyrodników Ziemi Łódzkiej. Łódź. Klaassen M., Beekman J., H., Kontiokorpi J., Mulder R., J., W., Nolet B. A Migrating swans profit from favourable changes in wind conditions at low altitude. J. Ornithol. 145:

17 Larsen J., K., Madsen J Effects of wind turbines and other physical elements on field utilization by pink-footed geese (Anser brachyrhynchus): A landscape perspective. Landscape Ecology 15: de Lucas M., Janss G., F., E., Ferrer M The effects of a wind farm on birds in a migration point: the Strait of Gibraltar. Biodiversity and Conservation 13: de Lucas M., Janss G., F., E., Ferrer M A bird and small mammal BACI and IG design studies in a wind farm in Malpica (Spain). Biodiversity and Conservation 14: Madders M., Whitfield D., P Upland raptors and the assessment of wind farm impacts. Ibis 148: Percival S Birds and windfarms: what are the real issues? Brit. Birds 98: Sachanowicz K., Ciechanowski M Nietoperze Polski. MULTICO, Warszawa. Steinof K Birds and windfarms: what are the real issues? Brit. Birds 99: Sikora A., Gromadzki M., Półtorak W Awifauna Bielawskich Błot. Not. Orn. 45:

18 Attachment 1 Dead skylark (Alauda arvensis) found under turbine no

19 Zoomed image of the skylark (Alauda arvensis) found under turbine no