Bird of the Year 2000 - Black Stork  

The Black Stork (Ciconia nigra) is rare summer migratory breeder and passage visitor to Georgia.
In Georgia species survives practically only in eastern part of country - in the flood-lands of Kura (Mtkvari) River (3-4 pairs), Alazani River (5-6), Iori River(2-3) and Khrami River(1-2);
- about 5 pairs are breeding on rocks and precipices in low and middle mountain belts of some ridges of Great Caucasus;
- 2-3 pairs probably still breed in old forests along banks of Rioni River;
- 3-4 pairs inhabit slopes of Trialethi Ridge in central part.
During last decade the total number of known breeding pairs ranged between 12 and 17.

Some phenological data for Black Storks in Georgia:
Spring transit migration February 3April 1
Arrival to nesting habitats March 3April 2
Clutching (first egg) April 28
Hatching May 6; May 11
Fledging beginningmiddle of July
Autumn migration August 2October 3

This bird in Georgia nests in two types of biotopes:
1. Riverine forests 120300 m a.s.l., primarily in the Kura River catchment area in the valleys of rivers such as the Kura (Mtkvari), Alazani, Iori, Ktsia (Khrami) rivers. This biotope is characterized by stratified forests (poplar {Populus alba}, asp {Populus tremula}, willows {Salix arbusticola, Salix vinimalis, Salix caprea}, blackberry {Rubus caesius, Rubus dolichocarpus}, sea buckthorn {Hippophae rhamnoides}, granate {Punica granatum}, lianes {Hedera spp., Smilax spp.} and other trees and bushes typical for Central Transcaucasia). Brushwood and reed patches are often found along the river banks; marshy areas and small freshwater lakes are found in these areas. The rivers often form fluvial systems with little islands that are favoured nesting sites for Black storks.
2. Old-growth forest tracts in the lower and middle mountain belts, 7001000 m a.s.l., this biotope consists of precipices, rocks, cliffs or rocky slopes and meadows and large glades. An essential feature of nest sites in this biotope is presence of river valley or floodland areas not more than 0.51.0 km from the nest.
Arrival at the nesting habitats in Georgia usually takes place in mid-March, with the extreme dates covering a wider range (March 3April 2). The birds start to repair or construct nests soon after their arrival in the nesting habitats.
It is interesting to notice that birds nesting in the riverine forest nest only in trees. The nests are most frequently constructed in 1018 m height on poplars. Birds nesting in the second type of biotope always nest on rocks. An interesting behaviourial difference has been observed between Black storks nesting in the two different biotopes: those nesting in trees on floodlands are very circumspect, while on the contrary, the mountain population does not react so much to the disturbance by man. According to data, collected in 1970''s-1990''s (A.Abuladze, B.Eligulashvili and G.Rostiashvili - The Black Stork in Transcaucasia, in press.), the average clutch size in Black Stork nests was 3.58. Of all eggs laid 16.8% remained unhatched. The average number of youngs fledged from successful nest was 2.7, while 28% of nests were not successful. The average size and weight of Black Stork eggs were 67.9 x 47.7 mm (n=17) and 80.8 g (n=10).
The main factor presently limiting number and distribution of Black Stork in Georgia is undoubtedly the destruction of nesting habitats, primarily through a reduction in floodland forest. Most of the forest removal occurs in the areas still inhabited by Black storks the valleys of large rivers. Although lowland forest removal is prohibited by Georgian nature conservation laws, the devastation still occurs illegally. Another serious threats to the local population of Black storks are the creation of reservoirs, illegal shooting and some other factors including changes in forms of agriculture, human disturbance, recreational pressure in nesting habitats, heavy grazing, and probably pesticides. Two accidental causes of mortality (collision with aerial electric conductors and electrocution) have also been registered.

Conservation status:
The Black Stork has been protected in Georgia since the early 1970''s and it has been included in the Red Data Book of Georgia (Red Data Book of Georgian SSR, 1982). Protection strategy of Black Stork in Georgia should be based on the traditional scheme of protection of rare birds:
a) survey and register all nesting sites;
b) actively protect all known nests, prohibiting tree-felling near sites and restricting human activities during the breeding season, i.e. reduce the level of disturbance;
c) strictly control illegal shooting;
d) intensively use mass media to promote ideas about protection among the local people;
e) develop long-term program for research, monitoring and protection of species in Georgia.


References:
Abuladze, A. 1984. Part Birds. In Fauna of typical biocenosies of Kolkhida Lowland. Academy of Sciences publishing house Tbilisi: pp. 127144. (in Georgian).
Abuladze, A. 1993. Seasonal migrations of the Black Stork in East Pontica. Abstracts of the 1st International Black Stork Conservation and Ecology Symposium (Latvia, Jurmala, 19-24 April 1993): p. 21.
Abuladze, A. 1993. The Black Stork in West and Central Transcaucasus. Abstracts of the 1st International Black Stork Conservation and Ecology Symposium (Latvia, Jurmala, 19-24 April 1993): p. 22.
Abuladze, A. 1993. The Black Stork in East Georgia in the 20th Century. Abstracts of the 1st International Black Stork Conservation and Ecology Symposium (Latvia, Jurmala, 19-24 April 1993): p. 23.
Abuladze, A. 1996. The Black Stork in the Caucasian countries: distribution, status and population changes. Abstracts of the 2nd International Conference on the Black Stork (Trujillo, Extremadura, Spain; 21-24.03.1996): p. 20 (in English & in Spain).
Abuladze, A., Kandaurov, A, Eligulashvili, V., Edisherashvili, G. 1986. Sostoyanie aistovykh ptits Gruzii [Status of the Storks in Georgia]. In: Izuchenie ptits SSSR, ih okhrana i ratsionalnoe ispolzovanie [Status of the Storks in Georgia. Study of Birds of the USSR. 1st Cong. of the Ornithological Society of the USSR and 9th All-Union Ornithological Conference]. Vol. 1, pp. 1920. (in Russian).
Abuladze, A.V., Shergalin, J.E. 1996. Migration of the Black Stork in Black Sea basin: results of 20 years studies. Abstracts of the 2nd International Conference on the Black Stork (Trujillo, Extremadura, Spain; 21-24 March 1996): p. 92 (in English & in Spanish).
Kutubidze, M. 1985. saqarthvelos phrinvelebis sarkvevi [The Guide to the Birds of Georgia]. Published by the Tbilisi State Univ.: 648 pp. (in Georgian).
Red Data Book of Georgian SSR (1982) Edited by N.Ketskhovely and B.Kurashvili. Tbilisi, "sabchota saqarthvelo" Publ. house: 255p. (in Georgian).
Zhordania, R.G. 1962. Ornitofauna Malogo Kavkaza (v granitsakh Gruzinskoi SSR)[Bird fauna of the Lesser Caucasus (within the limits of Georgian SSR]. Tbilisi. Academy of Sciences publishing house: 288 pp. (in Russian).
Abuladze, A., Rostiashvili, G., Eligulashvili, B. The Black Stork in Transcaucasia, 11 pages (in press.)


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