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Can the capercaillie (Tetrao urogallus) reintroduction be successful?
Stelšovská, Lenka ; Křenová, Zdeňka (advisor) ; Reif, Jiří (referee)
The western capercaillie (Tetrao urogallus) used to be a common species in Europe but, during the last decades, the species declined rapidly in the western part of its range, i.e. in Central and Western Europe. Decreasing of the habitat quality, inappropriate forest management, climate changes, disturbing by humans (sport & tourisms) together with very only low adaptabity of this species were recognized to be the most important factors threatening Tetrao urogallus. Also predation is a very important stress factor. Numbers of reintroduction projects have been conducted in Europe to improve the situation. This study summarizes current knowledge about reintroduction projects and their effectivity. Most of the projects were not successful very much. Reintroduction projects were implemented also in the Czech Republic in 1998 - 2007 and capercaillies have been released in several regions (Šumava, Český les, Krkonoše, Jeseníky, Moravskoslezské Beskydy, and Brdy). No new populations were established. The reasons for the failure have been found in the insufficient quality of the biotopes, predation, the physiological and ethological deficiencies of the young birds and the ways of their rearing. It is possible to summarize, that the reintroduction projects seem to be low effective but they are not completely...
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Communities of xylophagous insects in floodplain forest: distribution and host specificity
VODKA, Štěpán
During the last century the forests of Central Europe changed from open woodlands to even-aged stands with closed-canopy. This change resulted in severe decline of forest biodiversity. This study examines how, and why such change affected xylophagous insects. I have studied microhabitat preferences, i.e. distribution of xylophagous insects in canopy and understorey of closed forests, forest edges and wooded meadows. I used method of rearing insect from timber baits exposed to ovipositing females of xylophagous insects in different situations in the forest at the beginning if vegetation season. After one season of exposition,the baits were collected enclosed in fly-wire cages, where emerging insects were collected for two seasons. This thesis consists of two parts: The first part is an unpublished manuscript dealing with effect of habitat insolation, vertical stratification, forest structure and amount of dead wood on community of long-horned beetles (Cerambycidae) and jewell beetles (Buprestidae) feeding on wood of pedunculate oak (Quercus robur). Baits were exposed in the canopy and the understorey of forest interior, the canopy and the understorey of forest edge and on solitary trees on wooded meadows. Most insect species do prefer insoled wood for their development, and were more common in the understorey than in the canopy. Insolation of bait was thus the prime factor affecting composition of reared insects. No relation was found between dead wood volume and species composition or abundance of reared insects This shows that insolation of the dead wood is crucial to conservation of most xylophagous insects. The second part of the thesis studies effect of vertical stratification and insolation on distribution of xylophages feeding reared from wood of 8 tree species (Alnus glutinosa, Populus alba, P. x canadensis, Salix alba, Carpinus betulus, Quercus robur, Tilia cordata, Ulmus laevis) and host specificity of xylophages. Results show that: (i) community composition of xylophages reflects evolutionary history of their host plants; (ii) communities reared from different trees exhibit different preferences for forest strata and insolation of the habitat, probably in connection to preferred growth conditions of the host plant, (iii) many xylophagous insect species exhibit strong preferences to insoled habitats, and are thus confined to forest edges in extensively managed forests as well as in unmanaged forest reserves.
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