Ábrahám Levente (szerk.): Válogatott tanulmányok VII. - Natura Somogyiensis 22. (Kaposvár, 2012)

Winkler D. - Erdő Á.: A comparative study of breeding bird communities in representative habitats of the Sárosfő Nature Reserve area

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Natura Somogyiensis

Table 2: Ecological structural characteristics of bird communities in the different habitats

S - species richness, De - total bird density (pairs/10 ha), H' - Shannon’s diversity index, J - Pielou’s cquitabil- ity index, CDI - community dominance index (%)

5

De

H'

J

CDI

reedbed

4

6.19

1.205

0.8691

76.92

meadow

4

5.94

1.330

0.9591

66.67

oak afforestation

15

37.50

2.518

0.9299

28.57

oak forest

13

43.62

2.376

0.9265

31.71

ash-alder forest

26

64.54

3.013

0.9249

19.78

pine forest

8

29.03

2.043

0.9826

33.33

The most important structural characteristics of breeding bird communities are presented in Table 2.

Species richness ranged between 4 and 26 in the habitats surveyed (Fig. 2a). Only 4-4 species have been recorded in the reedbeds and meadow, while the habitat with the highest number of species (26) appeared to be the riverine ash-alder woodland. Species richness was relatively high (15) also in the young pedunculate oak afforestation. Bird communities in this shrub stage of secondary forest succession often include species characteristic for open habitats, like the Grasshopper Warbler (Locustella naevia), the Common Stonechat (Saxicola torquata) and the Yellowhammer (Emberiza citrinella) while typical shrubland birds like the Blackcap (Sylvia atricapilla), the Common Blackbird (Turdus merüld) are also present, often in high densities (Winkler 2005). We encountered only 13 species in the turkey oak-pedunculate oak forest. This low value of species richness can presumably be explained by the age of the surveyed forest stand (Waliczky 1991). Generally, habitats like these low pole stands are no longer appropriate for species nesting in shrubs such as warblers (Sylviidae) and not yet suitable for the hole-nesting ones like woodpeckers (Picformes), flycatchers (Muscicapidae) or tits (Paridae). From the forest habitats sampled, species richness was the lowest (8) in the

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Fi

g. 2a-d: Species richness, Shannon diversity, density and community dominance index