Changes in body size of living organisms can indicate changes in environmental quality. The family Carabidae is frequently used as an indicator of environmental status. We collected ground beetles in 9 Slovakian localities (in the Veporské vrchy Mts and the Juhoslovenská kotlina Basin) of various levels of disturbance, and evaluated the volume of individuals. The lowest average body volumes of individual were found for an intensively grazed pasture (locality 5) and a nitrophilous waterside vegetation (locality 6) (1,298 mm3–4,648 mm3) with predominantly macropterous species. We have confirmed the significantly higher average biovolume value of individual Carabidae in less disturbed habitats: a Picea abies plantation (locality 1), a Carpathian oak-hornbeam forest (locality 4) and a Carpathian turkey oak forest (locality 7) (from 9,837 mm3 to 13,038 mm3), where apterous and brachypterous species dominated.
The Carabidae family (Coleoptera) is used frequently for its bioindication potential to detect the environmental burden. In 2013 and 2014, we studied the correlation of Carabidae on the biotopes of six areas in the Veporské vrchy Mts and the Juhoslovenská kotlina basin by using pitfall traps, Möricke plates and Bambara beetle traps. Out of 432 recorded specimens of beetles (53 species, 15 families), the Carabidae family were the highest number of species and specimens represented, with which we confirmed higher anthropogenic interference and disturbance of ecosystems in the Juhoslovenská kotlina basin. This statistic confirms the presence of the following species typically found on arable land: Anchomenus dorsalis, Calathus fuscipes fuscipes, Harpalus affinis and Pseudoophonus rufipes. The ecosystems in the Veporské vrchy Mts region show less disturbance, and the anthropological impact is smaller, indicated by the presence of the Carabus problematicus species, an important indicator of the conservation of natural forest ecosystems.
The red-footed falcon and Eurasian falcon represent two syntopical falcon species. While the Eurasian falcon is considered a common and numerous species in Slovakia, the red-footed falcon population has undergone a considerable decline during the past few decades. Nowadays it nests in a single locality in Slovakia, the Sysľovské polia Special Protection Area, which forms the northern and fragmented border of the species distribution area in Europe. By analysing prey remains from 9 nests (from 1998, 2001, 2013, 2014 and 2016), we identified 433 prey items belonging to 35 taxa and 9 orders. Every year, invertebrates made up the major part of the diet spectrum, in which Calosoma auropunctatum, Tettigonia viridissima, Zabrus tenebrioides, Anisoplia aegetum and Rhizotrogus sp. were the most frequent species of prey. Of the vertebrates, Microtus arvalis was the most hunted prey species. By supplementary analysis of 21 photos, we extended our knowledge on the diet by other 6 taxa. The peak of the M. arvalis population growth in 2014 did not manifest itself in the red-footed falcon diet composition. In 1998, 2014 and 2016 we also studied the diet of a syntopical species, the Eurasian kestrel. By analysing prey remains in 22 nests, we identified 1,151 prey items belonging to 37 taxa and 7 orders. In 1998 and 2014 vertebrates predominated, especially the common vole, however in 2016 invertebrates prevailed. This fact could be a reaction to the M. arvalis population peak in 2014 and its decline in 2016. These results suggest that this variability in the foraging behaviour of the Eurasian kestrel, an opportunistic predator, during the hunting of invertebrates increases the diet similarity and overlapping of the food niche of both studied falcon species.
Ground beetles (Carabidae) were used to evaluate the bio indication environmental incidence. The ground beetle material (2,341 individuals, 30 species) was collected between 2015 and 2017 using pitfall traps in three types of forest habitats with different disturbance rates. The comparison of carabid’s sensitivity as bio indicators has been evaluated by using three methods: (i) community index of ground beetles (IKS), (ii) ellipsoid biovolume (EV) and (iii) flight ability of the carabids. Using the Monte Carlo permutation test, we did not record the statistically significant changes in IKS values, nor does a change in the representation of carabids in the bioindicative group A, E and R. On the contrary, we confirmed the statistically significant changes in the average values of ellipsoid biovolume in biotopes and between biotopes (the Friedman and Kruskal-Wallis test -ANOVA (p-value = 0.00)). A higher number of macropterous species were recorded in biotopes with high disturbance as compared to the biotopes with low disturbance.