| A.P. Kuchin, N.A. Zubakina "Saker Falcon in Altay and adjoining plains" |
1 Gorno-Altaisk State University, Gorno-Altaisk,Russia,
2 WWF-Altay, Choros-Gurkina-46, Gorno-Altaisk, Altay Republic, Russia, e-mail: inform@mail.gorny.ru
This paper is written on the basis of the field work carried out in the Altay Mountains and adjoining plains in 1963-1997. The field work usually started in mid-March. When the roads were unpassable due to snow melt we used horses. During this period we identified breeding territories, determined the dates of arrival of the birds and the onset of the breeding period. Then, after small break we revisited the nest sites and look at the breeding parameters. At this time we usually used a car or a motorbike. A breeding territory was thus visited up to 8-10 times during the breeding period. One nest found in 1963 we revisited 42 times, sometimes even visited the nest (including climbing the tree). Besides we also used help of students during the field work.
ResultsLight morph Sakers of the plains.
Now lets look at the observations on the Sakers in the plains of the Altay. In 1993 we were observing a nest close to Biysk town. At the nest we obtained one young and one adult male and two chicks in down of 2 and 4 days old (probably were blown away from the nest by a storm).
The adult male weigh 800 g had wings 37 cm, tail 23 cm, and tarsi 6 cm. Young weigh 830 g (a day before fledging), wing 23 cm, tail 20 cm, tarsi 6 cm. The chicks in down weigh 40.5 g. The nest was located on a tree close to the clearcut-line 2 km from the edge of the forest, and3 km from the town. There was a nest of Crested Honey Buzzard in 300 m from the Saker nest. The Saker nest was originally built by a Black Kite and had paper, cloth and a copper wire 1 m long inside. There were no soft stems inside the nest, but large particles of soil. The nest diameter was 60x40 cm.
The chicks were hatching 8-11 May. During a strong storm (side-wind 26 m/s) on 14 May two young chicks were blown away from the nest. Two remaining chicks were male and female. The male hatched first and was heavier during first period of growth. In the first 10 days the male gained weight at 38 g per day, next 7 days - 50 g per days. At the age of 1 month its weight was 830 g. When the first contour feathers appear the weight dropped - at the age of 1 months after fledging (the chick was kept in captivity) its weight was 735 g.
The hatched chicks were in white down. On the 10 th day it was replace by grey down. On the 15 th the rectrices and primaries coverts appear in pins. They voice also changes at this age. On 20 th day the difference between male and female started to show up; the chicks started to freeze up if an observer appear. On 25 th day the tail coverts and head feathers appear. However on the cheeks, back, and belly the feathers are only in pins. The tarsi grow at the rate 2 mm per day in female and 1.6 mm per day in male. The tarsi stop to grow at the age of 25 days. The chicks left the nest on the third week of July. The male was at the age of 42 days, female on 41 day. The wings and tails of the chicks were still growing. The male was kept in captivity for a month and its wing grow for 8 cm and reached the length of 37 cm, while the tail grew 3 cm and reached 23 cm.
During the breeding period the behaviour of young male is different from that of female. The male is more movable and more noisy, the female is quiet and does not call if the humans are around. Behaviour of the parents is also different. After few days after hatching the female is brooding very tight: it did not leave the nest when we hit the base of the nesting tree with an axe; it flew away only if we climbed the tree. Once (on 18 May) we managed to grab the bird by hand. During cold days the female incubates, in hot days it stands on its feet and shades the broods.
Only male does the hunting. At the end of the first half of the months after hatching the female meets the male in the air, takes the prey and returns back to the nest. From 25 May the female started to hunt herself.
When the nest was visited by humans, the Sakers did not show any alarming behaviour. After few circle flights they land on the tree not far away and observed the visit from a distance. However they have different reaction if there is another bird of prey around. In 1963 we saw Sakers chasing away birds of prey approaching the nest. In 1965 we observed the opposite behaviour: there no aggressive actions to the birds of prey, however there were nests of Goshawk and Buzzard (Kuchin 1968).
Another nest of Saker was found at the Shubenka river, on the Biya-Chumish highlands, in 1965. The nest was found on a distance of 100 m from the edge of the forest patch of 25b ha. There was a nest of goshawk on a distance of 300 m on one side and a nest of a Buzzard in 300 m on another side. The Saker nest was built on a pine tree branch on the height of 8 m, and had 60 x 60 cm external dimensions. On 4 June there were 5 chicks in the nest (4 females and 1 male) with the age of 15-20 days. On 14 June females weigh 1000, 1100, 1250 and 1300 g, and male 970 g, they were supplied with the rings D-510979, D-510983, D-510989, D510990, D-510992.
In 1963 we found a disintegrated nest and the chicks were sitting on the branches of the tree. Part of the food items were fallen to the ground: there were many corpses of Sousliks underneath. The same picture we say in 1965 described above. First time after fledging the broods stick together close to the nest, however the distance increases from day to day. In the both nests the chicks fledged in approximately one calendar time - 18-20 June. In the same forest patch along the Shubenka river close to the Veselogo village we find a nest of Saker on 12 may 1966. In 1965 the nest was occupied by the Imperial Eagle. The nest was located at the edge of the forest and was built at the top of the pine tree on the height of 25 m. The nest contained 5 eggs of the dimensions 54.0-53.5 x 43.0-41.0 mm and weigh 48.6-44.0 g. The female was incubating. All eggs were removed and donated to the collection of the Zoological Institute, Leningrad (via R.I.Mayshevskiy). Four eggs contained embryos, the fifth one was infertile. The eggs were light brown coloured with rusty-brown large and small spots.
On 25 May 1967 we found an occupied nest of Saker Falcon in a pine forest between the Biya and Katun rivers. The was in fact an old nest of the Black Kite and was located on a clearing line, on the same place where the Sakers were breeding in 1963. It is possible that they were the same birds. The nest contained 5 chicks of 3-8 days old in down. The estimated hatching date was 17-22 May. In this year the spring was late, so we consider this was a late breeding. The female was brooding very tight, the male was seen close by. There were plenty of food remains around the nest.
On 29 May 1971 we found an old nest of the Imperial Eagle which was occupied by Sakers. The nest was located on a pine tree in a forest patch along the Shubenka River on the Biya-Chumish highlands. The nest contained 4 chicks in down of approximately 10 days of age. Three largest chicks were of the same dimensions, but the fourth one was significantly smaller. The weather was cold with snowfall and heavy winds, so the female was brooding all the time. The male was also close by. In the same place, on 6 May 1972 at the Shubenka river we found an old nest of a bird of prey occupied by Sakers. Due to difficult access to the nest we did not manage to see inside the nest. In the same forest on the Biya-Chumish highlands close to the Veselaya village in an old nest of the Imperial Eagle we found a Saker. On 10 May 1980 in the nest we found a female brooding clutch of 5. While examining the nest we squashed 2 eggs. Three remaining eggs had dimensions 50 x 39 mm, weight 51.5 g, 50 x 40, weight 53 g, 50 x 38 weight 49.5 g. The nest was revisited on 31 May and contained 3 chicks: one weigh 367 g and was covered with grey down and had primaries in pins, another weigh 168 g and was covered with grey down, and the third one weigh 130 g. On the revisit of the nest on 6 June the first chick weigh 900 g (after measurements and weighing the chick instantly died), second chick weigh 600 g and was ringed with the ring number C-277711, the third chick weigh 500 g was ringed with the ring number C-277713. On 1 July there were 2 fully fledged chick in the nest. One of them flew away and landed some 100-150 away.
One Saker nest was found in 1982 in Biya-Chumish highlands at the Chemirovka river, close to the Lozhkino village. The nest was known as a Buzzard nest in 1981. On 14 June we found 5 chicks in the nest. The chicks dimensions are given below.
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On 16 july the chicks had the following dimensions:
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The nest was revisited on 18 July and had only 4 chicks. The fifth chick was lying dead under the nest, presumably blown away by the wind. The chicks were ringed with the rings A-100611, A-100612, A-100613, A-100614. On 3 July there were only three chicks in the nest, the fourth chick already fledged and was seen away from the nest. The nest was partially disintegrated, some of the nest material was on the ground under the tree.
An old Imperial Eagle nest found on a birch tree along the Shubenka river was occupied by Saker in 1983. On 13 May the female was brooding the clutch of 5 eggs, on 12 June there were 5 chicks in the nest. Their dimensions are given below.
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In the same nest the Saker were breeding again in 1985. On 24 May there were 4 small chicks in the nest (weight 83.5, 65.9, 60 and 38.5 g) and one piped egg (44 g). On 29 May the chicks body weight was 260, 200, 198, 94 and 40 g. On 16 June there were only 4 chicks in the nest, they were marked with rings C734102, C734103, C734104 and C734105.
A nest of Saker built on a birch tree was found on the Kulunda and Suetka watershed close to the Melnikova village in 1985. In mid-July there were 4 chicks in the nest. In the following year the nest was not occupied.
Dark morph Sakers of the mountains.
The populations of the north-eastern part of the Saker range have several colour morphs. The light colour morph is considered to be a nominative, however there is a black (melanistic) morphs. The plains around the Altay Mountains are inhabited by the light (nominative) morphs. The dark morph is living in the mountain parts of the Altay, however the quantitative proportion of the dark morph is not established (Stepanyan 1990). The sightings of the dark morph of Saker in Altay is given in figure 1. In the Ursil Steppe, Central Altay, close to the Elo village we found a nest in the niche of a cliff with two chicks or dark morph on 25 June 1968. Another two chicks lied dead under the nest cliff. In the Ursil Steppe, close to the settlement Tenga we say a black morph adult on 14 June 1974. Pair of dark morph Sakers was seen in the Kansk Steppe between Yabogan and Ust-Kan on 7-8 September 1974, on 13 September 1987, and on the Tenga Lake 6-9 September 1980. E.A.Ireev obtained two specimens of the dark morph females on the Ukok plateau, one at the lake Chembak-Kul on 16 June 1964, and another at the sources of Ak-Koli river on 27 August 1965, and two males: one at the lake Chembak-Kul on 19 August 1964, and in the middle part of the Kolguta river on 28 August 1965.
The Saker Falcon population in the plains of the Altay breeds exclusively in trees, whereas the mountain population breeds on cliffs. The nest of the Saker found in the Ursul steppe at the Elo village was located in the niche of a cliff faced south-east. On the 15 June 1968 the nest contained 2 fledglings with not fully grown primaries. There were 3 long-tailed sousliks in the nest, as well as 3 fresh pellets containing fur and bones of souslicks, many fresh feathers of Rock Doves. The niche also contained a thick layer of old faeces of the birds as well as fur bones of sousliks, birds and feathers. It looked that the Sakers were breeding here for several years. E.A. Orlova and V.R. Ilyashenko (1978) found 4 nests of Sakers in South-Chuya Mountain Range. One of the nests was a massive one built of dry branches on the ledge of a cliff along the river Kushonur. The second was located on a clay cliff at the Kushonur river mouth. On 20 June it contained one chick in down. On 24 June they found a nest in cliffs along the Kushkunur river with one chick in down and one un-hatched egg. The second nest contained on a cliff ledge in the side of Chagan-Uzun valley. The nest visited on 28 June contained 4 chicks in down. On 25 July the first chick fledged, on 30 July all chicks were seen at the cliff close to the nest.
The remains of Altay Snowcock, 5 Ptarmigan, snow finch, 2 coughs, 1 Yellow-billed Chough, 2 Long-tailed Souslicks, one marmot and Northern Pika. Twelve pellets contained remains of 3 Ptarmigan, and Yellow-Billed Chough. Besides at the nest there were many feathers of young Altay Snowcocks, Coughs, and Horned Skylarks. On 1 July 1986 a Saker nest was found in 4 km south of Dzhulu-Kul lake. The nest was located on the cliff rock surrounded by stony slope on the altitude 2500 m. The nest contained 3 chicks in down at the stage of opening tips of rectrices and primaries. The nest also contained remains of Red-billed and Yellow-Billed Chough. Another pair of Sakers was found nesting in 11 km from the pair above, and was located in the eastern slope of the Maktay mountain, at the altitude of 2600 m. On 27 June 1986 there were chicks in the nest (it was possible to hear their calls) and also alarmed adults (Maleshin 1987). On 5 June 1986 another nest of Sakers were found in the Ulandryk river valley (South-Eastern Altay). The nest contained 5 chicks of age about a week. The nest was built on a ledge of a 121 m high cliff on altitude 2300-2900 m (Malkov 1987).
The population of Sakers in the mountains has obvious differences to the plain population in ecology, morphology and biology. High-mountain birds start breeding later and have shorter breeding period. Shortening of the breeding period on the high altitutes is explained by severe climatic conditions. Birds living in the highlands are known to have lower breeding rate due to constrains in food (Lack 1957).
Breeding successEggs and chicks mortality of Sakers at the plains is not high. Only one egg in 12 known nests was infertile. Two chicks were found dead after being blown away from the nest, another chick was also found dead under the nest. Presumably it was blown away by wind too, or was pushed away by another broods. A total of 46 chicks were produced by 11 nests in the plain part of Altay, or 4.2 per nest. Out of 8 nests the mountain part of the Altay a total of 20 chicks fledged, which makes 2.5 chicks per pair. The average breeding rate in the mountain part of the Altay is smaller perhaps of the abrupt changes in daily temperature in the mountains.
DietThe diet of the Sakers changes in the seasons of the year. In 1963 in the Biysk environs we collected 20 pellets, all of which contained fur of small rodents. The composition of the pellets suggests that during the first half of the months, when the chicks were fed by the male, the diet consisted of small rodents. In the second half of their development, when the female started to hunt, the diet was dominated by red-cheeked souslicks.
The switch of the diet from the small rodents to souslicks is explained not only by the fact that the females do catch large prey, but also that the young souslicks start to appear on the surface (Kuchin 1968). For the whole period of the same year during 42 visits to the nest we collected 18 red-cheeked souslicks, 20 pellets of the fur and bones of the souslicks, one hamster, 3 grey voles, 26 pellets of fur and bones of voles, 4 quail, snipe, Turtur Dove, and 2 young starlings. (Kuchin 1976). In 1965 on the Biya-Chumish highlands in the sources of the Shubenka river the diet of the Sakers was a bit different. During the first ten days of June the Sakers feed exclusively on the Fieldfares. The specialisation on Fieldfares was explained by a massive dispersal of young fieldfares in this regions. In the second ten-days period the Sakers started to hunt souslicks, all hunts were made within 1 km from the nest. The Sakers managed to raise all 5 chicks successfully. In the four nests of Sakers in this region in 1960, 967, 1983 and 1985 we collected feathers of fieldfares and skylark, 2 red-cheek souslicks, starling, teal, 41 pellets of fur and bones of red-cheeked souslicks. All data suggest that the diet of the Sakers dominated by the red-cheeked souslicks and small rodents (Kuchin 1969).
Winter movements.The departure of the Sakers in the plain steppes, forest-steppes and foothills start from the end of August to the mid-September. Normally the dates of the departure of the Sakers from the steppes coincide with the onset of hibernation of the red-cheeked souslicks (Kuchin 1969). The last sightings of the Sakers were recorded at the Ob river at the Klepikovo village on 7 September 1986, in the mouth of the Katun river 13 September 1979, in the Charish river valley at the Korgon settlement on 19 September 1964. However at these dates the Sakers are common in the mountain valleys of the Central Altay where the long-tailed sousliks are not yet hibernated. In the Kansk and Ursul steppes we saw the Sakers on 2-4 September 1988, 7-8 September 1984, 11-13 September 1987.
Some part of the population winters in the Altay mountains. In the Ursul steppe one could see them at the wintering places of livestock where the Sakers hunt for Rock Doves. On the slopes of the Terektinskiy Range in the proximity of the Kulady villages we saw Sakers on 7 October 1982, 14 November 1981. Another bird was recorded in the Tuekta river mouth on 14 November 1981. We saw in November-December 1981 at the shepherds camps at the sources of the Malaya Ilgumen rivers. The sakers were noted here in January-February 1982 while they were hunted Rock Doves (Kuchin 1983). The Sakers also winters in the South-Eastern Altay, on the Saylugem ridge, in the Chuya steppe (Derevshikov 1974). E.A.Irisov saw Sakers in the first half of February 1983 at three locations in the Chuya steppe (pers. comm.).
In 1960-70s the range and the density of the red-cheeked sousliks in the plain steppes and forest steppes of the Altay was on increase. In some parts of the range there was an advance of the range into un-touched steppe was 10-15 km. In the Biya-Chumish highlands between the rivers Chemrovka and Shubenka in May 1967 we captured 12 souslicks into 20 gin-traps set on the area 0.5 ha during the period of 2 hours. (Kuchin 1995). The density of common hamster was also high: on 5-6 km of arable land we found 15-20 occupied burrows. In the middle May we used to catch 15-18 hamsters in 20 traps per night. High concentrations of sousliks and other rodents attracted several species of birds of prey. In the forest patches along the rivers of Chemrovka and Shubenka there were nests of Imperial Eagle, Great Spotted Eagle, Black Kite, Buzzard, Goshawk, Sparrowhawk, Eurasian Kestrel as well as Saker. In the mid 1980s the numbers of Red-cheeked Souslicks started to decline. Because of the depression of the red-cheeked sousliks and other rodents birds of prey stopped breeding. The last Saker breeding was observed in 1986. In South-Eastern Altay at the Chuya depression (1750-1900), surrounded by the mountains has features of the Mongolian semi-desert with scarce vegetation, acute continental climate and little precipitation, severe winters late and cold spring and cool and dry summer. Saker is one of the characteristic birds of the Chuya steppe. In 1987-1997 we have had 139 routes scheduled in the dispersal time of the young Sakers. Normally we counted 60 Sakers in one year. In the past 20 years the numbers of Sakers declined due to decline of the sousliks and pressure from humans.
In the end of 1970s beginning of 90s the Sakers were common birds in the Chuya steppe (Derevshikov 1974).
Species decline is very obvious from the result of the counts in the past 10 years. In the period of 1986-1990 we registered 44 Sakers during 5 years. In five years from 1991-97 there were only 16 birds counted. Similar tendency of the decline was observed in the subsequent years. In the 5 days of field work in the Chuya steppe (31 August 4 September 1999 we say only one Saker. At the moment there are some administrative measures imposed to prevent illegal trapping and export of Sakers.
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Kuchin, A.P. 1968. Observations on the Siberian Saker in the Upper Ob river. Ornitologia 9: 103-107.
Kuchin, A.P. 1969. Diet of birds of prey and owls in Altay. Proc. All-Union Ornithol. Conf, Ashabad, 2: 330-333. (In Russian).
Kuchin, A.P. 1976. Birds of Altay. Non-Passeriformes. Barnaul. 230 pp.
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Kuchin A.P. 1995. Dynamics and structure of biogeocenosus of the Biya-Chumish highlands in 20 century. In: Proc. 2 International scientific conference Ecology and conservation. Part 1. Perm: 59-61. (In Russian).
Lack, D. 1957. Numbers of animals and their regulation in the nature. Russian Edition, Moscow. 403 pp.
Maleshin, N.A. 1987. New data on the rare birds of the Altay Nature reserve and adjoining territories. In: Extinct, rare and little-studied plants and animals of the Altay region and problems of their conservation. Proceedings of the conference, Barnaul : 87-88. (In Russian).
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Orlova, E.A. and Ilyashenko, V.Yu. 1978. Materials on the diet of some diurnal birds of prey and owls of South-Eastern Altay. Proc. Zool. Institute, 76: 94-100. (In Russian).
Stepanyan, L.S. 1990. Conspectus of the ornithological fauna of the USSR. Moscow, Nauka publishers. 726 pp.
Proceedings of the II International Conference on the Saker Falcon and Houbara Bustard, Mongolia, 1-4 July 2000. - P. 44-54.
