Open Access BASE2008

Проблема «Птицы и ЛЭП»: есть и положительный аспект

Abstract

Birds are adapted for the environment conditions. However human began to change many nature conditions and change inhabitant places of many bird species. One of the most powerful factors, that provoked birds to occupy new inhabitant places, was the overhead power line system development. There are many publications about bird electrocution (Pererva, Blochin, 1981; Pererva, Grazhdankin, 1983; Lanovenko, Abdulnazarov, 1983; Saltykov, 1999; Karyakin et al., 2005; Karyakin, Barabashin, 2005; Karyakin, 2008; Medzhidov et al., 2005; Matsyna, 2005; 2006; Karyakin, Novikova, 2006) and this problem need the immediate solution. But in this paper I want to emphasize another side of the problem the positive impact of power lines to improve nesting conditions for many raptor species. Since the power line appearing birds began to use electric poles as perches during breeding season and migrations. However soon birds began to use electric poles and for nest building. The Raven (Corvus corax) began to inhabit power lines in forest-steppe of Russia on 10 years later than the Jackdaw (C. monedula) and the Rook (C. frugilegus) in 1980-s and has begun to spread in the steppe zone only since 1990-s. I had already found tens of raven nests on electric poles in steppes of the Middle Volga in 1995-98. The species only has begun to spread in Western Kazakhstan. There is the paper about the process of raven spreading through power lines in the Cis-Caucasus region: Belik V.P. et al., 2004. The first nest of ravens on an electric pole was found in that region in 2000. The Carrion and the Hooded Crows (Corvus cornix, C. corone)are the latest species of Corvidae who have begun to use electric poles for the nest building. Now 0.7% pairs of Hooded Crows, 4% pairs of Rooks, 30% pairs of Ravens and 55% pairs of Jackdaws build nests on electric poles in the steppe zone of the Volga-Ural region. After Corvidae birds of prey began to occupy electric poles in the forest and forest-steppe zones. The first raptors who began to nest on electric poles were little falcons the Kestrel (Falco tinnunculus) and the Red-footed Falcon (Falco vespertinus). Only pairs of Kestrels and Red-footed Falcons bred in the south of the Perm district in 1980-s. The number of Kestrel and Red-footed Falcon nests located on electric poles has increased to 22% and 5% accordingly in the Volga-Ural region till 2007. The first event of the Hobby (Falco subbuteo) nesting in the electric pole was registered in the Ulyanovsk district 29 July 2005. Only the Long-eared Owl (Asio otus) amongst all species of owls began to occupy nests of Corvidae (usually nests of Jackdaws) built on electric poles. There are known 5 such nests. Steppe Eagles began to use electric poles in desert and semi-desert regions in the south of Russia and Western Kazakhstan. The Steppe Eagle nesting on wooden electric poles had been already noted in Kalmykia at the end of 1970-s (Survillo et al., 1977), however the species nested almost only on the ground until 1950-s and began to nest on thatch ricks only in 1950-70-s and on electric poles in 1970-80-s (Bostanzhoglo, 1911; Kozlov, 1959; Savinetskiy, Shilova, 1986; 1996). Similar process was note in Western Kazakhstan. The Steppe Eagle nesting on concrete electric pole crossarms was found in the Pre-Ural region in 1982 (Pererva, Grazhdankin, 1983). The species had occupied to nest metal and concrete poles widely in the Ural and Emba river basins already to the end of 1990-s. Now 27.3% of the total number of known nests (n=286) is built on electric poles, 52,6% of which is located on concrete pole crossarms (Karyakin, Novikova, 2006). Now the Steppe Eagle has already begun to nest on metal electric poles (15-20 m height) of power lines with high voltage in Kalmykia, the Lower Volga region, Western and the south of Central Kazakhstan, unfortunately it is isolated cases (Belik, 2004; author's information). By the way the Steppe Eagle is not noted to nest on electric poles in the north of his own range in the Samara district (Karyakin, 2002), in the west of the Orenburg district, as well as in Eastern Kazakhstan (Smelyanskiy et al., 2006) and in Southern Siberia (Karyakin et al., 2006) that are inhabited the large breeding populations of the species. Now only western subspecies of the Steppe Eagle (A. nipalensis orientalis) uses electric pole for nesting, but the eastern subspecies (A. n. nipalensis) has not yet been registered to nest on electric poles. The power line infrastructure development is believed to impact on the Long-legged Buzzard spreading in Western Kazakhstan. M.N. Korelov (1962) supposed the species not to breed or breed rarely in the territory between The Volga and the Ural rivers, however the species was found near the Elton Lake and Janybek in 1964, and 39 nests located mostly in large willows in the territory of leaved villages and on wood electric poles had been already known till 1982 (Lindeman, 1983). V.I. Pererva and A.V. Grazhdankin noted 3 nests on electric poles in the Pre-Ural Mountains region (1983). The number of the Long-legged Buzzard had being increased in the Volga-Ural semideserts till 1990-s, as the result the species have inhabited all suitable territories in the region. (Lindeman et al., 2005). Now more than 80% of local breeding groups of the Long-legged Buzzard nest on electric poles in most regions of Western and the west of Central Kazakhstan. The Upland Buzzard inhabiting mountain steppes in Mongolia and Southern Siberia as well as the Long-legged Buzzard began to nest on electric poles but it seemed to be later mostly since the end of 1970-s. The Upland Buzzard was not noted to nest on electric poles in Northern Mongolia in 1960-s (Pichocki, 1968). However the species nesting on electric poles was common in Central Mongolia at the end of 1990-s (Potapov et al., 2001). Surveying the Upland Buzzard in Tuva А.А. Baranov (1991) found 27 nests of the species located only on cliffs and trees, but nothing on electric poles. However near 40-50% of the Upland Buzzard nests had been already registered on electric poles (by the way only on wood poles) in 1999.The species seemed to begin to nest on electric poles in Tuva since 1991 to 1999. The Upland Buzzard was found to nest on electric poles in Khakassia in 2000. A.V. Davygora (1999) was the first who found the Imperial Eagle nesting on the electric pole in the woodless valley of the Irgiz river. Also active nests of the Imperial Eagle on electric poles were found in the Ustyurt Plateau and the Aral Sea region in 2003 (Karyakin et al., 2004). We found 5 pairs of the Steppe Eagle and 3 pairs of the Imperial Eagle nesting on electric poles in the Aral Sea region in 2003, however only pair nested on the electric pole in 2006, but the number of Imperial Eagle pairs increased to 9. Almost all nests of Steppe Eagles besides one were occupied by Imperial Eagles. Besides Steppe Eagles Imperial Eagles also forced Saker Falcons (Falco cherrug) out and occupied 2 nests, where falcons bred earlier. As the result the density of breeding pairs of Imperial Eagles in the monitored fragment of power line increased from 2.01 to 6.03 pairs/100 km of power line while the density of Steppe Eagles decreased from 2.68 to 0.67 pairs/100 km of power line during 4 years (Karyakin, 2006). The Emperial Eagle breeding on electric poles was noted in the Emba river basin in the Kinderli-Kayasanskoe Plateau in 2004 (Levin, Karyakin, 2005), between the Turgay and Zhilanchik rivers in the south of the Kostanay district (Bragin, 2005) and in Eastern Betpak-Dala (Levin, Karpov, 2005). Also nests of Imperial Eagles on electric poles with the density 0,53 pairs/100 km of power line were surveyed in the lower reaches of the Syrdarya river to the east of the Aral Sea in 2005 (Karyakin et al., 2005), in steppes to the north of the Ulutau Mountains (Karyakin, Barabashin, 2006) and Western Betpak-Dala. Two living nests on electric poles were found in the Mugodzhary Mountains in 2006, and one of them was actually occupied by Steppe Eagles in 2004 (Pazhenkov et al., 2005); 1 in the Kalbinskiy Altai foothills (Smelyanskiy et al., 2006). We known 200 breeding pairs of the Imperial Eagles in Kazakhstan in 2006, 25 of which (12.5%) nested on electric poles, while 10 of them forced Steppe Eagles out in 2005-2006 (Karyakin, 2006). Visiting Western Betpak-Dala once again in 2007 we noted the number of nests on electric poles to increase at least in 2 times in contrast with 2005. All facts the Imperial Eagle expansion mentioned above were registered only in semidesert regions of Kazakhstan. The first active nest of the Imperia Eagle located on the concrete electric pole crossarm was found in the steppe in the territory of the Kostanay district of Kazakhstan on 24 May 2007, and the nest with 2 fledglings located on the metal electric pole was found in the forest-steppe in the north-east of the Samara district of Russia on 7 August 2007. The Black-eared Kite (M. m. lineatus) was the first subspecies of the Black Kite which began to nest on electric poles. The Black-eared Kite began actively to nest on metal electric poles along the Enisey river valley in the Tuva depression in 1999-2006. There were 12 nests near Kyzyl and Ak-Dovurak till 2006. The Black Kite breeding on the metal electric pole was registered in the Republic of Altai in 2000, later a breeding colony consisting of 11 active nests and located on metal electric poles was found in the Chuya steppe. The first nest of the Black Kite on the electric pole was found in the Minusinsk depression in 2006. The first living nest of the Osprey (Pandion haliaetus) built on the top on the metal electric pole was found in the Kerzhenets river valley in the N. Novgorod district in 2007. V.G. Kolbintsev (2004) noted the Short-toed Eagle (Circaetus gallicus) nesting on the electric pole in the desert near Kyzylkol Lake in the Maly Karatau Mountains foothills. Also A.V. Kovalenko (pers. com.) surveyed a nest of the Short-toed Eagle on the electric pole in the south-eastern Kazakhstan. The Golden Eagle (Aquila chrysaetos) nesting on electric poles was found in the Ustyurt Plateau: 2 nests located in metal electric poles were visited in 2003 (Karyakin et al., 2004). The Buzzard (Buteo buteo) only one of 1113 found nests in the Ural region located on the metal electric pole in deciduous forest was registered in the Chelyabinsk district (Karyakin, 1998). Following the Upland Buzzard and the Raven the Saker Falcon occupying their nests began to inhabit electric poles in Mongolia in 1970-s. The Saker pairs breeding on artificial structures (55.3%) were considered to outnumber the pairs on the natural substrates in the Central Mongolia at the end of 1990-s (Potapov et al., 2001). Sakers nesting on electric poles were registered in Tuva in 1990-s. Surveying Sakers in Tuva A.A. Baranov (1991) did not found any nests of falcons on electric poles. However Sakers were noted to occupy Upland Buzzard nests on wooden electric poles in the Ubsunur and Tuva depression in 1999. Local herders cut down poles with 9 nests of sakers in the left side of the Tes-Chem river since 1999 to 2003, 93.3%, of saker nests (n=13) were destroyed in the steppe region near Agar-Dag-Taiga Mountains during 7 years (Karyakin, 2005а; 2005б), the all 3 poles with saker nests were cut down near the Cheder and Chadyn Lakes in the Tuva depression. A pair of Sakers was noted to breed in the Raven nest on the wooden pole of only functioning power line in 2006. As the result of power line destroying by herders and poaching the number of Sakers decreased in Tuva and falcons has not begun to nest on metal electric poles. Sakers breeding on electric poles were not found in the all territory of the range in Western Siberia and Northern Kazakhstan. The first and last nest of the Saker made by Ravens on concrete electric pole were existing in the north-west of the Orenburg district in the European part of Russia during 2 years in 1998-99 (Karyakin et al., 2005). Sakers has not registered in the Volga and Pre-Ural regions since 2005. The largest density of the Saker was registered on following poles of power lines located in Eastern Betpak-Dala and the Balkhash Lake region (Kazakhstan): in fragments with metal double poles 10.6 pairs/100 km; in fragments with concrete poles 5.6 pairs/100 km, in fragments with single metal poles 7.9 pairs /100 km. The minimal density (3.9 pairs/100 km) was noted for the power line in the territory of military polygon (Levin, Karpov, 2005). Only nest of Sakers made by Imperial Eagles was found on the concrete pole in Western Betpak-Dala in 2005 (Karyakin, Barabashin, 2006). Also Sakers nesting on metal and concrete poles of the power line locating in the Sarysu river basin in south-west of the Kazakh Upland in 2007. Sakers breeds sufficiently sporadically in sands of the Aral Sea region. A.V. Kovalenko (pers. com.) found 2 pairs of Sakers breeding on concrete poles of power line along the Syr-Darya river in 2005. Four pairs were registered in nests made by eagles on concrete poles of the destroyed power line 183 km in length in the Bolshye Barsuki sands in 2003 (Karyakin et al., 2005). Now Sakers are not found to breed on electric poles to the west of the Bolshye Barsuki sands in Kazakhstan and Russia up to the Western Ukraine. Thus the power lines using by birds are distinguished in different regions and years. Appearing in bird inhabitant places power lines impact differently on different subpopulation of the species and it depends on different factors. The most distinguished differences of developing abilities to nest on electric poles development adaptation are revealed between the Steppe and Imperial Eagles. Escaping negative factors pairs of the Steppe Eagle western subspecies began to use electric pole for nesting in optimal breeding habitat, but the Imperial Eagle began to use electric pole as the result of moving from optimal to sub-optimal habitats. Our research confirms power lines to be very important for creating subpopulations of raptor species in untypical places for raptors and therefore and influence development of population structure of those species. From one hand their adaptation to nest on electric poles especially in human disturbed territories promotes their survival. But from another hand birds become to depend on the power engineering management. Now when extensive using of electric poles by raptors is noted, the special program need for collaboration between ornithologists and power engineering specialists for bird protection from electrocution. ; Birds are adapted for the environment conditions. However human began to change many nature conditions and change inhabitant places of many bird species. One of the most powerful factors, that provoked birds to occupy new inhabitant places, was the overhead power line system development. There are many publications about bird electrocution (Pererva, Blochin, 1981; Pererva, Grazhdankin, 1983; Lanovenko, Abdulnazarov, 1983; Saltykov, 1999; Karyakin et al., 2005; Karyakin, Barabashin, 2005; Karyakin, 2008; Medzhidov et al., 2005; Matsyna, 2005; 2006; Karyakin, Novikova, 2006) and this problem need the immediate solution. But in this paper I want to emphasize another side of the problem the positive impact of power lines to improve nesting conditions for many raptor species. Since the power line appearing birds began to use electric poles as perches during breeding season and migrations. However soon birds began to use electric poles and for nest building. The Raven (Corvus corax) began to inhabit power lines in forest-steppe of Russia on 10 years later than the Jackdaw (C. monedula) and the Rook (C. frugilegus) in 1980-s and has begun to spread in the steppe zone only since 1990-s. I had already found tens of raven nests on electric poles in steppes of the Middle Volga in 1995-98. The species only has begun to spread in Western Kazakhstan. There is the paper about the process of raven spreading through power lines in the Cis-Caucasus region: Belik V.P. et al., 2004. The first nest of ravens on an electric pole was found in that region in 2000. The Carrion and the Hooded Crows (Corvus cornix, C. corone)are the latest species of Corvidae who have begun to use electric poles for the nest building. Now 0.7% pairs of Hooded Crows, 4% pairs of Rooks, 30% pairs of Ravens and 55% pairs of Jackdaws build nests on electric poles in the steppe zone of the Volga-Ural region. After Corvidae birds of prey began to occupy electric poles in the forest and forest-steppe zones. The first raptors who began to nest on electric poles were little falcons the Kestrel (Falco tinnunculus) and the Red-footed Falcon (Falco vespertinus). Only pairs of Kestrels and Red-footed Falcons bred in the south of the Perm district in 1980-s. The number of Kestrel and Red-footed Falcon nests located on electric poles has increased to 22% and 5% accordingly in the Volga-Ural region till 2007. The first event of the Hobby (Falco subbuteo) nesting in the electric pole was registered in the Ulyanovsk district 29 July 2005. Only the Long-eared Owl (Asio otus) amongst all species of owls began to occupy nests of Corvidae (usually nests of Jackdaws) built on electric poles. There are known 5 such nests. Steppe Eagles began to use electric poles in desert and semi-desert regions in the south of Russia and Western Kazakhstan. The Steppe Eagle nesting on wooden electric poles had been already noted in Kalmykia at the end of 1970-s (Survillo et al., 1977), however the species nested almost only on the ground until 1950-s and began to nest on thatch ricks only in 1950-70-s and on electric poles in 1970-80-s (Bostanzhoglo, 1911; Kozlov, 1959; Savinetskiy, Shilova, 1986; 1996). Similar process was note in Western Kazakhstan. The Steppe Eagle nesting on concrete electric pole crossarms was found in the Pre-Ural region in 1982 (Pererva, Grazhdankin, 1983). The species had occupied to nest metal and concrete poles widely in the Ural and Emba river basins already to the end of 1990-s. Now 27.3% of the total number of known nests (n=286) is built on electric poles, 52,6% of which is located on concrete pole crossarms (Karyakin, Novikova, 2006). Now the Steppe Eagle has already begun to nest on metal electric poles (15-20 m height) of power lines with high voltage in Kalmykia, the Lower Volga region, Western and the south of Central Kazakhstan, unfortunately it is isolated cases (Belik, 2004; author's information). By the way the Steppe Eagle is not noted to nest on electric poles in the north of his own range in the Samara district (Karyakin, 2002), in the west of the Orenburg district, as well as in Eastern Kazakhstan (Smelyanskiy et al., 2006) and in Southern Siberia (Karyakin et al., 2006) that are inhabited the large breeding populations of the species. Now only western subspecies of the Steppe Eagle (A. nipalensis orientalis) uses electric pole for nesting, but the eastern subspecies (A. n. nipalensis) has not yet been registered to nest on electric poles. The power line infrastructure development is believed to impact on the Long-legged Buzzard spreading in Western Kazakhstan. M.N. Korelov (1962) supposed the species not to breed or breed rarely in the territory between The Volga and the Ural rivers, however the species was found near the Elton Lake and Janybek in 1964, and 39 nests located mostly in large willows in the territory of leaved villages and on wood electric poles had been already known till 1982 (Lindeman, 1983). V.I. Pererva and A.V. Grazhdankin noted 3 nests on electric poles in the Pre-Ural Mountains region (1983). The number of the Long-legged Buzzard had being increased in the Volga-Ural semideserts till 1990-s, as the result the species have inhabited all suitable territories in the region. (Lindeman et al., 2005). Now more than 80% of local breeding groups of the Long-legged Buzzard nest on electric poles in most regions of Western and the west of Central Kazakhstan. The Upland Buzzard inhabiting mountain steppes in Mongolia and Southern Siberia as well as the Long-legged Buzzard began to nest on electric poles but it seemed to be later mostly since the end of 1970-s. The Upland Buzzard was not noted to nest on electric poles in Northern Mongolia in 1960-s (Pichocki, 1968). However the species nesting on electric poles was common in Central Mongolia at the end of 1990-s (Potapov et al., 2001). Surveying the Upland Buzzard in Tuva А.А. Baranov (1991) found 27 nests of the species located only on cliffs and trees, but nothing on electric poles. However near 40-50% of the Upland Buzzard nests had been already registered on electric poles (by the way only on wood poles) in 1999.The species seemed to begin to nest on electric poles in Tuva since 1991 to 1999. The Upland Buzzard was found to nest on electric poles in Khakassia in 2000. A.V. Davygora (1999) was the first who found the Imperial Eagle nesting on the electric pole in the woodless valley of the Irgiz river. Also active nests of the Imperial Eagle on electric poles were found in the Ustyurt Plateau and the Aral Sea region in 2003 (Karyakin et al., 2004). We found 5 pairs of the Steppe Eagle and 3 pairs of the Imperial Eagle nesting on electric poles in the Aral Sea region in 2003, however only pair nested on the electric pole in 2006, but the number of Imperial Eagle pairs increased to 9. Almost all nests of Steppe Eagles besides one were occupied by Imperial Eagles. Besides Steppe Eagles Imperial Eagles also forced Saker Falcons (Falco cherrug) out and occupied 2 nests, where falcons bred earlier. As the result the density of breeding pairs of Imperial Eagles in the monitored fragment of power line increased from 2.01 to 6.03 pairs/100 km of power line while the density of Steppe Eagles decreased from 2.68 to 0.67 pairs/100 km of power line during 4 years (Karyakin, 2006). The Emperial Eagle breeding on electric poles was noted in the Emba river basin in the Kinderli-Kayasanskoe Plateau in 2004 (Levin, Karyakin, 2005), between the Turgay and Zhilanchik rivers in the south of the Kostanay district (Bragin, 2005) and in Eastern Betpak-Dala (Levin, Karpov, 2005). Also nests of Imperial Eagles on electric poles with the density 0,53 pairs/100 km of power line were surveyed in the lower reaches of the Syrdarya river to the east of the Aral Sea in 2005 (Karyakin et al., 2005), in steppes to the north of the Ulutau Mountains (Karyakin, Barabashin, 2006) and Western Betpak-Dala. Two living nests on electric poles were found in the Mugodzhary Mountains in 2006, and one of them was actually occupied by Steppe Eagles in 2004 (Pazhenkov et al., 2005); 1 in the Kalbinskiy Altai foothills (Smelyanskiy et al., 2006). We known 200 breeding pairs of the Imperial Eagles in Kazakhstan in 2006, 25 of which (12.5%) nested on electric poles, while 10 of them forced Steppe Eagles out in 2005-2006 (Karyakin, 2006). Visiting Western Betpak-Dala once again in 2007 we noted the number of nests on electric poles to increase at least in 2 times in contrast with 2005. All facts the Imperial Eagle expansion mentioned above were registered only in semidesert regions of Kazakhstan. The first active nest of the Imperia Eagle located on the concrete electric pole crossarm was found in the steppe in the territory of the Kostanay district of Kazakhstan on 24 May 2007, and the nest with 2 fledglings located on the metal electric pole was found in the forest-steppe in the north-east of the Samara district of Russia on 7 August 2007. The Black-eared Kite (M. m. lineatus) was the first subspecies of the Black Kite which began to nest on electric poles. The Black-eared Kite began actively to nest on metal electric poles along the Enisey river valley in the Tuva depression in 1999-2006. There were 12 nests near Kyzyl and Ak-Dovurak till 2006. The Black Kite breeding on the metal electric pole was registered in the Republic of Altai in 2000, later a breeding colony consisting of 11 active nests and located on metal electric poles was found in the Chuya steppe. The first nest of the Black Kite on the electric pole was found in the Minusinsk depression in 2006. The first living nest of the Osprey (Pandion haliaetus) built on the top on the metal electric pole was found in the Kerzhenets river valley in the N. Novgorod district in 2007. V.G. Kolbintsev (2004) noted the Short-toed Eagle (Circaetus gallicus) nesting on the electric pole in the desert near Kyzylkol Lake in the Maly Karatau Mountains foothills. Also A.V. Kovalenko (pers. com.) surveyed a nest of the Short-toed Eagle on the electric pole in the south-eastern Kazakhstan. The Golden Eagle (Aquila chrysaetos) nesting on electric poles was found in the Ustyurt Plateau: 2 nests located in metal electric poles were visited in 2003 (Karyakin et al., 2004). The Buzzard (Buteo buteo) only one of 1113 found nests in the Ural region located on the metal electric pole in deciduous forest was registered in the Chelyabinsk district (Karyakin, 1998). Following the Upland Buzzard and the Raven the Saker Falcon occupying their nests began to inhabit electric poles in Mongolia in 1970-s. The Saker pairs breeding on artificial structures (55.3%) were considered to outnumber the pairs on the natural substrates in the Central Mongolia at the end of 1990-s (Potapov et al., 2001). Sakers nesting on electric poles were registered in Tuva in 1990-s. Surveying Sakers in Tuva A.A. Baranov (1991) did not found any nests of falcons on electric poles. However Sakers were noted to occupy Upland Buzzard nests on wooden electric poles in the Ubsunur and Tuva depression in 1999. Local herders cut down poles with 9 nests of sakers in the left side of the Tes-Chem river since 1999 to 2003, 93.3%, of saker nests (n=13) were destroyed in the steppe region near Agar-Dag-Taiga Mountains during 7 years (Karyakin, 2005а; 2005б), the all 3 poles with saker nests were cut down near the Cheder and Chadyn Lakes in the Tuva depression. A pair of Sakers was noted to breed in the Raven nest on the wooden pole of only functioning power line in 2006. As the result of power line destroying by herders and poaching the number of Sakers decreased in Tuva and falcons has not begun to nest on metal electric poles. Sakers breeding on electric poles were not found in the all territory of the range in Western Siberia and Northern Kazakhstan. The first and last nest of the Saker made by Ravens on concrete electric pole were existing in the north-west of the Orenburg district in the European part of Russia during 2 years in 1998-99 (Karyakin et al., 2005). Sakers has not registered in the Volga and Pre-Ural regions since 2005. The largest density of the Saker was registered on following poles of power lines located in Eastern Betpak-Dala and the Balkhash Lake region (Kazakhstan): in fragments with metal double poles 10.6 pairs/100 km; in fragments with concrete poles 5.6 pairs/100 km, in fragments with single metal poles 7.9 pairs /100 km. The minimal density (3.9 pairs/100 km) was noted for the power line in the territory of military polygon (Levin, Karpov, 2005). Only nest of Sakers made by Imperial Eagles was found on the concrete pole in Western Betpak-Dala in 2005 (Karyakin, Barabashin, 2006). Also Sakers nesting on metal and concrete poles of the power line locating in the Sarysu river basin in south-west of the Kazakh Upland in 2007. Sakers breeds sufficiently sporadically in sands of the Aral Sea region. A.V. Kovalenko (pers. com.) found 2 pairs of Sakers breeding on concrete poles of power line along the Syr-Darya river in 2005. Four pairs were registered in nests made by eagles on concrete poles of the destroyed power line 183 km in length in the Bolshye Barsuki sands in 2003 (Karyakin et al., 2005). Now Sakers are not found to breed on electric poles to the west of the Bolshye Barsuki sands in Kazakhstan and Russia up to the Western Ukraine. Thus the power lines using by birds are distinguished in different regions and years. Appearing in bird inhabitant places power lines impact differently on different subpopulation of the species and it depends on different factors. The most distinguished differences of developing abilities to nest on electric poles development adaptation are revealed between the Steppe and Imperial Eagles. Escaping negative factors pairs of the Steppe Eagle western subspecies began to use electric pole for nesting in optimal breeding habitat, but the Imperial Eagle began to use electric pole as the result of moving from optimal to sub-optimal habitats. Our research confirms power lines to be very important for creating subpopulations of raptor species in untypical places for raptors and therefore and influence development of population structure of those species. From one hand their adaptation to nest on electric poles especially in human disturbed territories promotes their survival. But from another hand birds become to depend on the power engineering management. Now when extensive using of electric poles by raptors is noted, the special program need for collaboration between ornithologists and power engineering specialists for bird protection from electrocution.

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