Ábrahám Levente: Biomonitoring a Dráva folyó magyarországi szakasza mentén 2000-2004 - Natura Somogyiensis 7. (Kaposvár, 2005)

Dombi, Imre: Bat monitoring along the Drava River (Mammalia: Chiroptera) - Denevér-monitoring a Dráva mentén (Mammalia: Chiroptera)

148 NATURA SOMOGYIENSIS detectors or by capturing the animals well represent the bat-fauna and also the stock-size. Although the forested area is bigger the chosen sampling spots are reliably characterise distinctive habitats. Methods applied: capture and sampling with detectors - line transect method. 3. Vízvár Reasons for the choice: Drava River enters Hungary above the village again, thus any impact present still in Croatia can be well indicated in the area. Forestation is very good in the region, meaning exclusively willow-poplar groves. Because of the closeness of the settlement, both building-dwelling and forest stock can be well observed on the sampling sites. General classification: The area is situated right next to Drava, thus its effect is obvious. We can find softwood gallery forest remained in their natural condition with a rich shrub level and undergrowth. The main species are white willow (Salix alba), and poplars (Populus sp.). The old forests offer the hole-dwelling bats great roosts. Distributaries and temporarily flooded areas supply the bats with very good foraging sites during the whole active period. The attics of buildings and the church in the settlement are the roost sites of the building-dwelling species, which does not usually make up big colonies, but lead a solitary life or live in colonies of only some individuals. These species feed on the floodplains, too. However, the lights in the streets should also be mentioned since they function as light-traps attracting insects that the bats willingly exploit. Methods applied: capture, sampling with detectors - line transect along the bank of Drava and in the settlement and point counting at the distributary of Drava. 4. Babócsa Reasons for the choice: The Mérus forest is a relict-like, old, hardwood forest that represents a very important habitat due to its island-like features. Because of the collecting effect, many sensitive species are found here in greater or smaller number. The current of the Drava, the changing groundwater level has a great impact on the health, the renewability of the forest that indirectly effects the bats, too. The backwater of Drava once a river-basin, now one backwater of the river, which is filling up steadily. The old willows in the surroundings offer great habitats for the Daubenton's bat (Myotis daubentoni) and the pond bat (Myotis dasycneme), as they are strongly related to water due to their life-style. General classification: Nature-like forest, where the main and additional species of trees are also present. It is at least 500 meters away from the water and takes up 80 ha (~200acres). It is surrounded by big meadows and turfs and offers excellent roost sites. Openings and the surrounding open flooded habitats are good foraging sites. The whole district is heterogene concerning both age-distribution and diversity. The backwater of the Drava is filling up, it is flooded during high-water, but by the end of the summer it almost dries out completely. The old willows (Salix sp.) in the bank-lane give great roost sites and the big open watersurface and the groves offer a good foraging site for the bats. Methods applied: capture in the oak forest, sampling with detectors - line transect in the oak forest and between the backwater of Drava and point count at the backwater of Drava.