In 2017, we investigated the population dynamics and flying activity of the south-east European endemic dragonfly species Cordulegaster heros Theischinger, 1979. This research was conducted in the southern part of Central Slovakia in the Revúcka vrchovina Upland at a submountainous stream called Drienok. The mark-release-recapture method was applied to study the population. Cordulegaster heros was observed 775 times during the midsummer season. We found out that the species has bimodal diurnal activity pattern with a highest peak from 17:00 until 19:00 hours, but the species had a short peak before noon as well. The differences between sexes in the sense of entering new individuals to the population were low during the main flying period. Estimated population size for males surpassed the population size of females. Probability of capture decreased by the end of the flying season without differences in sexes. This article is the first on the flying activity and population dynamics of Cordulegaster heros.

189 specimens of 75 species of sawflies were collected at Cerová vrchovina Upland (South Slovakia).

During the second year of the investigation, 281 specimen of 75 species of sawflies were collected at Cerová vrchovina (South Slovakia) (Figs. 1 and 2). Rare species are:

Cordulegaster heros is included in the EN category on the IUCN Red List for the territory of the Czech Republic, where it inhabits an area of approximately 100 km2. All of the localities are located in the forest complex in Chřiby hills, and all of the forests fall into the category of management forests. Most of the forest stands have a high and very high degree of naturalness; they are natural forest stands. The predominant management units are Nutrient sites in middle elevations (78.2 % of the area) and Oligotrophic sites in middle elevations (2.1 % of the area), with stand types of Fagus sylvatica representing 92.5 % of the area, and forest stand types of Quercus sp. representing 5.7 % of the area. The wider alluvia in forest streams are classified as being in management unit alder and ash sites on waterlogged and floodplain soils (1.1 %), with the forest stand type of Alnus glutinosa. The forest stands are restored by regeneration under shelterwood (97.8 % of the area). The waterlogged alluvia, if a separate management unit is established for them, are restored by a regeneration by strip method. Realistically, seven factors were recorded in C. heros habitats, but they mostly have only point effects. Within forestry management, the factors of logging directly in the habitats and the subsequent transport of harvested timber in the habitat were recorded. The most intrusive effects were found on tractor logging roads, where fine soil washes into the stream and causes prolonged turbidity. Of the water management structures in the study area, logging roads with bridges and culverts are constructed, stream banks are reinforced with longitudinal walls at points, and stone steps in the channels are constructed only sporadically. The current forest management system can be described as a nature-friendly system, and therefore, it fully ensures the conditions for the survival of the C. heros population in the Czech Republic.

No abstract