Ábrahám Levente (szerk.): Válogatott tanulmányok IX. - Natura Somogyiensis 24. (Kaposvár, 2014)

Szűcs D. - Kitti Horváth K. - Horváth Gy. F.: Comparing small mammal faunas based on barn owl (Tyto alba) pellets collected in two different lowland landscapes

Szűcs, D., Horváth, K. & Horváth, Gy. F.: Small mammal faunas

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Table 3: Results of ANOVA tests, based on relative frequencies of small mammal taxa with significant abundance

Faj/taxon

Kruskal-Wallis (H)

one-way ANOVA (F)

P

S. araneus

14.20

<0.01

C. suaveolens

17.09

<0.01

M. agrestis

13.79

<0.01

M. oeconomus

23.24

<0.05

A. amphibius

13.31

<0.01

A. agrárius

5.87

<0.001

Apodemus genus

3.29

<0.05

Neomys genus

14.48

<0.01

Soricidae

2.90

<0.05

between FVS and DS (RS = 0.96; P < 0.001), while we reported the lowest value in the case of two sample pairs (NHS vs. CS and NHS vs. KS: RS = 0.48 - 0.49, P < 0.05). However, the high values of homogeneity test also showed that the distribution of species frequencies was inhomogeneous in the comparison of the microregions (x2 = 160.07 - 2437.31, P < 0.001). Based on the frequency distribution of small mammals, the percentage overlap was higher between landscapes which were in the same geographical region than in the comparison of two investigated mesoregions (Table 3). This result confirmed that the percentage overlap values between small mammal assemblages of landscapes increased as the spatial scale was refined.

Data analysis of local scale, based on niche parameters

The statistical evaluation of niche parameters on the local spatial scale showed that the niche breadth of the bam owl did not differ (t = 0.35, n.s.) in the comparison of the Drava plain and the Győr basin. The box plot diagram also illustrated the lack of statistical difference of the average niche breadth caused by the great overlap of the confidence interval (Fig. 7). Thus, there is high similarity in the food composition in both landscapes. Considering the faunistic data this is a realistic result, because the prey list of the two investigated landscapes deviated from only one species (root vole). Based on this result we did not reject the null-hypothesis for niche-breadth.

The value of niche overlap (0//t) was significant between the three data groups (ANOVA: F = 11.29, P < 0.01) (Fig. 8). Due to the overlap of food composition between the breeding pairs of settlements in the regions, the value of niche overlap was significantly higher within the two mesoregions than between them (post hoc LSD-test: DS vs. DS-GYM: P = 0.00064, GYM vs. DS-GYM: P = 0.00214), so we rejected the third null hypothesis for niche overlap.