Page 30 - NZDPM 33/2017

Nesting habitats of Black Stork (Ciconia nigra L.) in Ukrainian forest zone … 29

Table 3

Distribution (%) of Black Stork nests in the forests of different productivity classes
in relation to general frequency distribution of those classes in the region

Forest In 500m In buffers around In the entire
productivity Nests locations buffers random points study area
classes (n=108)
(bonitet) n % % % % ha
1 40 40,8 33,7 32,4 35,9 140720
1A 11 11,2 8,6 10,8 10,2 39971
1B 0 0,0 0,7 1,0 0,8 3015
1V 0 0,0 0,0 0,3 0,1 239
1G 0 0,0 0,1 0,1 0,1 246
2 30 30,6 37,1 35,9 33,9 132850
3 12 12,2 12,3 12,9 11,4 44573
4 2 2,0 5,1 3,3 4,3 17002
5 2 2,0 1,5 1,8 1,9 7605
5A 1 1,0 0,8 1,4 1,3 4962
5B 0 0,0 0,3 - 0,1 560
Total 98 100 391742

Nesting trees
The majority of studied nests in Ukrainian Polissya are located on oaks (table 4). Other
important tree species for storks is pine. All other tree species comprise less than 17% of all
the cases. Such proportion is typical for all the studied sub-regions of Polissya and is similar
to the findings of other researchers in Ukraine [5, 16, 17, 20] and in some regions of Europe
[3, 8, 19]. The proportion of nests on various trees may differ from study to study [6, 8, 15]
and might be strongly dependent on the availability of different tree species in the studied
areas. At the same time, oak seems to be one of the most preferable trees in all the cases when
it is available. Nesting trees were usually very old – older than the surrounding forest stand.
Unfortunately, we do not possess any data on the exact tree age to compare it with the
published studies, but the same tendency was observed in all the works cited above.

Table 4

Numbers of Black Stork nests located on different tree species
in the Ukrainian Forest zone (Polissya)

Regions
Tree species Total %
Volyn Rivne Zhytomyr Kyiv Chernihiv Sumy
Oak 27 69 60 21 16 7 200 53,3
Pine 29 35 20 7 15 7 112 29,9
Alder 14 9 2 - 2 1 28 7,5
Silver birch 4 3 5 - 1 - 13 3,5
Common aspen 2 7 7 - - - 16 4,3
Ash 1 - - - - - 1 0,2
Willow - - - - 3 2 5 1,3
Total 77 123 94 28 37 17 375 100