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TABLE 3. OCCURENCE OF THE NESTS OF CINEREOUS VULTURE AT GREAT CAUCASUS ACCORDING TO THE SLOPE EXPOSURE
(N =116)
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Slope location |
Number of nests |
|
No |
% |
|
North |
6 |
5,17 |
|
North-East |
9 |
7,76 |
|
East |
17 |
14,65 |
|
South-East |
33 |
28,49 |
|
South |
26 |
22,41 |
| South-West |
12 |
10,34 |
|
West |
9 |
7,76 |
| North-West |
4 |
3,49 |
|
Total: |
116 |
100,00 |
TABLE 4. OCCURENCE OF THE NESTS OF CINEREOUS VULTURE AT GREAT CAUCASUS ACCORDING TO THE EDGE HABITATS
(N = 116)
|
Habitats |
Number of nests |
Comments |
|
No |
% |
|
Solitary tree |
4 |
3,49 |
All in eastern and central areas of Azerbaijan |
|
Scattered trees |
15 |
12,93 |
11 in Azerbaijan and 4 in SE Georgia |
|
Open forest |
24 |
20,69 |
All in W Azerbaijan and SE Georgia |
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Semi-open forest |
66 |
56,90 |
Everywhere |
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Closed forest |
7 |
6,03 |
6 in North Caucasus and 1 in Georgia |
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Total: |
116 |
100,00 |
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NESTS
Caucasian Cinereous Vultures nest exclusiveli in trees, most often are used old Junipers Juniperus ssp. - in 91 cases out of recorded 116.
The Foedit Juniper Juniperus foetidissima Willd. is the most preferred nest tree in the Central Transcaucasus (n=69). Nesting in Greek Juniper Juniperus polycarpos was observed rarely, only twenty-one nest was found during our study. Besides that, nests were found in Pistachio-trees Pistacia mutica (n=7) and Eldar Pine-trees
Pinus eldarica (n=6). The nesting in other tree species was recorded only four times and may be classified as occasional (Table 5).
All known five nests of the Cinereous Vulture in the North Caucasus were placed in pine trees, always in tops.
Nest sizes of Caucasian Cinereous Vultures (116 nests in Central Transcaucasus and 8 nests in other regions) were the following:
D=120-215 cm, d=40-85 cm, H=40-120 cm and h=15-40 cm.
TABLE 5. NEST-TREE SELECTION BY CINEREOUS VULTURE AT GREAT CAUCASUS (N = 116)
|
Species of nest -tree |
No |
Height of nest above ground (m) |
|
|
-2 |
2-4 |
4-6 |
6-8 |
8-10 |
10-12 |
12-15 |
15+ |
|
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|
Foedit juniper Juniperus foetidissima |
69 |
1 |
10 |
23 |
26 |
7 |
2 |
- |
- |
|
|
Greek juniper
Juniperus polycarpos |
21 |
- |
2 |
10 |
8 |
1 |
- |
- |
- |
|
|
Juniperus rufescens |
1 |
- |
- |
1 |
- |
- |
- |
- |
- |
|
|
Pistachio tree
Pistacia mutica |
7 |
- |
- |
1 |
5 |
1 |
- |
- |
- |
|
|
Eldar Pine-tree
Pinus eldarica |
6 |
- |
- |
1 |
3 |
1 |
1 |
- |
- |
|
|
Other pine species
Pinus spp. |
9 |
- |
- |
- |
1 |
1 |
4 |
2 |
1 |
|
|
Other tree species |
3 |
- |
- |
- |
1 |
|
1 |
1 |
- |
|
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Total: |
116 |
1 |
12 |
36 |
44 |
11 |
8 |
3 |
1 |
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COPULATION
Copulation of Cinereous Vultures in Central Transcaucasus was observed between
27 February and 16 March.
52 cases of copulations observed being divided into three groups:
a). successful copulations - copulations with cloacal contact;
b). unsuccessful copilations - copulations without cloacal contact;
c). undetermined copulations - all those cases of copulations, could not be classified as either of the a or b groups.
At least 36 or about 3/4 of all the copulations observed were classified. In 29 cases copulations were successful.
25 copulations takes place on the nest or not far from them (three observations) and one in 120 m from nest 1-4 times per day.
Duration of the observed copulations was from 10 to 30 seconds.
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CLUTCH Egg-lying. Single egg is laying at the end of February-beginning of March. Case of egg-replacing by new one instead of the lost one was recorded only 2 times. The complete normal clutch of Cinereous Vulture consists of 1 egg that is recorded in 502 cases for the Central Caucasus and in 9 cases for the other regions.
Only in one case in the Vashlovani Nature Reserve in SE Georgia, clutch of two eggs was discovered (see photo). Probably it was the joint clutch of 2 females in 1 nest.
Sizes of eggs (n=61) of the birds from Central Transcaucasus were the following: length -84,0-96,3 mm, width 64,5-72,5 mm, weight (n=34) 225,7-236,3 g. One egg was considerably larger 98,3 x 73,0 mm, 247 g and three eggs were considerably lesser: 78,5 x 62,5 mm, 218,2 g; 80,0 x 65,0 mm, 222,1 and 81,5 x 65,0 mm, 221 g.
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INCUBATION Duration of incubation was recorded for 25 clutches. Incubation, that begins after laying of egg, lasting 53 (n=2), 54 (n=16), 55 (n=6) or 56 (n=1) days and the both parents take part in it. Incubating bird sits in nest always by back towards sun.
Chick hatching is going in April (11.04 - 30.04).
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