Preferencje help
Widoczny [Schowaj] Abstrakt
Liczba wyników

Znaleziono wyników: 21

Liczba wyników na stronie
Pierwsza strona wyników Pięć stron wyników wstecz Poprzednia strona wyników Strona / 2 Następna strona wyników Pięć stron wyników wprzód Ostatnia strona wyników

Wyniki wyszukiwania

help Sortuj według:

help Ogranicz wyniki do:
Pierwsza strona wyników Pięć stron wyników wstecz Poprzednia strona wyników Strona / 2 Następna strona wyników Pięć stron wyników wprzód Ostatnia strona wyników
5
100%
The article overviews the role of bats in the forest ecosystem (especially the European forest), the impact of environmental pollution on the forest and bats, and the issue of bats indication of the forest environment condition. Existing data on the transfer of pollutants to the environment and between the aquatic and terrestrial environment are reviewed. The water environment is an important receiver of industrial pollution, which then transfer to the terrestrial environment i.a. through insect larvae. Bats as predators hunting for the insects, which undergo part of their life cycle in water (including Diptera: Chironomidae), play an important in this cycle. Another source of bats intoxication are terrestrial insects feeding on plants that transfer toxins that settle on the leaves surface further in the food chain. Bats as predators of the first or even second level store in such a case substances like heavy metals in their bodies. Air pollutants also have a direct impact on forest stands, causing (in zones of strong industrial pollution) the inhibition of tree growth. The result is, among other things, a smaller number of hollows, which in turn is manifested indirectly through weaker settlement by bats (and birds) of these stands. Bats communities inhabiting the forest depend on such factors as the availability of roosting places, the age structure and spatial structure of the stands. All these features (as well as others related to them) are subject to modification through economic forestry, which causes changes in the bat communities. Ecological research of forest bats shows variability of settling of managed stands, as well as diversified species composition, especially smaller presence of typically forest bats connected ecologically with forests (e.g. western barbastelle Barbastella barbastellus or lesser noctule Nyctalus leisleri), in favor of bats preferring open spaces and built−up areas (serotine bat Eptesicus serotinus). This is probably the result of changes in the age and spatial structure of the stand. On the basis of the collected information, it was concluded that bats are a valuable indicator of the condition of the forest environment.
The echolocation calls of the noctule bat Nyctalus noctula {Schreber, 1774) were recorded at night, from June to August 1991, using a QMC S20Q bat detector, in 5 habitats (river, forest-meadow eeotone, village, coniferous forest, deciduous forest) of the Białowieża Primeval Forest (eastern Poland). Two main kinds of signals were identified: search calls and feeding buzzes. Acoustic activity was high over the rivers, in the forest-meadow eeotone and in small woodland villages. It was negligible inside the coniferous and deciduous forests. The differences among habiLats were especially evident in the case of feeding buzzes; no feeding was recorded inside deep deciduous forests. Two peaks in overnight activity were found, with maxima after sunset and before sunrise. Intraseasonal changes of activity were recorded; the highest activity was in July.
The paper presents the project of a crevice box designed especially for Western barbastelle Barbastelle barbastellus bats. Barbastelle is endangered species of bat protected throughout the Europe and included in Annex II of the EU Habitats Directive. In many forest areas of Natura 2000 Barbastelle is official subject to protection, which imposes certain obligations on the area’s administrator or landowner. Western Barbastelle in forests uses atypical roosts (comparing to most other bats), which are cracks of trunks and crevices under the bark of trees, especially deciduous trees. For this reason, it is most often found in old deciduous forests abounding in such potential shelters. As an endangered species, it often requires active protection, and bat−boxes used so far are not settled by Barbastelles because they do not correspond to their ecological preferences. For this reason, it was necessary to develop a project of boxes that would correspond to the preferences of this species and will be settled by these bats. Typical bat−boxes are the equivalent of tree hollows carved by woodpeckers, while crevice boxes to a greater extent than previous solutions imitate natural cracks in tree trunks. Similar boxes were successfully introduced in the United Kingdom by Greenaway and Hill [2004], and then tested on a larger scale in forests in Poland by Rachwald i in. [2018]. Boxes were successfully occupied by individual bats and by breeding colonies, which does not happen in bat boxes with a traditional construction. The paper contains a concise description of the obtained so−far results of colonization bat−boxes by Barbastelle and a sketch of the newly redesigned box with detailed dimensions (fig. 2). Based on the positive results of experiments with the colonization of this type of boxes, it is proposed to use these boxes as an at least temporary solution for the active protection of Barbastelles in forests wherever there is a shortage of natural shelters.
Bats were netted at two sites over the forest rivers Narewka and Hwoźna in Białowieża Primeval Forest (E Poland), during the summer of 1994 and 1995. A total of 452 bats of 11 species were captured. The number of bats netted each night was positively correlated with the minimum air temperature. The rate at which the three commonest species - Nyctalus noctula, Myotis daubentonii and Nyctalus leisleri - were caught varied significantly through the night, with a major peak after sunset. For N. noctula air temperature was apparently positively related to the size of the morning peak.
Pierwsza strona wyników Pięć stron wyników wstecz Poprzednia strona wyników Strona / 2 Następna strona wyników Pięć stron wyników wprzód Ostatnia strona wyników
JavaScript jest wyłączony w Twojej przeglądarce internetowej. Włącz go, a następnie odśwież stronę, aby móc w pełni z niej korzystać.