L. Forró szerk.: Miscellanea Zoologica Hungarica 13. 2000 (Budapest, 2000)

Horváth, Gy.; Pintér, V.: Small mammal fauna of two abandoned field habitats, and a spatio-temporal analysis of four rodent populations

MISCELLANEA Tomus 13. ZOOLOGICA HUNGARICA 2000 p. 105-121 Small mammal fauna of two abandoned field habitats, and a spatio-temporal analysis of four rodent populations by Gy. Horváth and V. Pintér (Received July 15, 1999) Abstract: In the present study the authors investigate the small mammal fauna of two abandoned field habitats with different vegetation in the Dráva Lowlands, and the spatio-temporal changes of four rodent species found there, based on live-capture data from 1997-1998. The sampling areas are situated in the plain area of the rivulet Fekete-víz: one near the village Páprád, in a swampy area, which was not cultivated for four years, and the other near the village Nagycsány, in an area, which had been abandoned for one year. Based on their small mammal diversities, the two areas did not differ. Four species were captured in great numbers in both of the habitats: M. arvalis, A. agrárius, A. sylvaticus and A. flavicollis. For the characterisation of their dynamics, we applied minimum number alive (MNA) values, and for describing the spatial distribution of the individuals within the population, Lloyd's patchiness was used. Keywords: live trapping, diversity, population dynamics, spatial distribution, Apodemus, M icrot us Introduction Drawbacks from habitat fragmentation, and the formation of island characteristics appear nowadays as important factors from the point of view of the survival of communities (Soulé 1986, Harrison 1994). From the 1980s the metapopulation concept has gained strength also in small mammal ecology (Krohne 1897). As a result of human activities, natural and nearnatural areas suffer fragmentation, and habitats composed of patches of various size are created that small mammals can utilise with characteristic spatial and temporal dynamics (Kozakiewicz 1995). From a metapopulation aspect, it is mainly the seasonal dynamics of Clethrionomys glareolus (Schreber 1780) that has been studied in patchy agrocenoses (Kozakiewicz & Gortat 1994), and also its space use in such patchy environments was analysed (Kozakiewicz et al. 1993). Lonan (1991a), too, investigated the small mammal communities of such fragmented habitats, with special attention to the dispersal dynamics of Apodemus sylvaticus (Linnaeus, 1758) in patches. The small mammal fauna of a habitat complex similar to the areas subject to our studies were analysed by Pelikán & Nesvadbová (1979). The paper by AdamczewskaAndrzejewska et al. (1981) focuses on the relationship between three rodent populations (Microtus arvalis [Pallas 1779], Apodemus agrárius [Pallas 1771] and Apodemus flavicollis [Melchior 1834]) in cultivated lands; these species play a dominant role also in our sample community. The spatial organisation of the same communities was analysed by Adamczewska-Andrzejewska et al. (1979) and Mackin-Rogalska (1981). Hannsson (1968) conducted long-term population dynamical surveys in open habitats in Sweden, and he analysed separately the small mammal runways in abandoned areas (Hannsson 1987). Among the general ist, rather forest-dwelling species, it is A. sylvaticus the populations of which have been studied in open habitats (Jamon 1986, Loman 1991b, Fernandez 1996).