Vergleichende Untersuchungen zu zwei Laichpopulationen der Erdkröte (Bufo bufo Linneaus, 1758) im Raum Halle (Saale)

Abstract

Karl, S.; Grosse, W.-R.: Comparison of two common toad (Bufo bufo Linneaus, 1758) breedingpopulations in ponds of the Halle (Saale) region (Saxony-Anhalt). – Hercynia N. F. 43 (2010): 319 –336.Mobile guiding fences were used to study the migratory behaviour of two populations of the commontoad and to examine morphometric parameters and population age structures. The first study site (‘KreuzerTeich’) lies in a city park, the second one (with two spawning waters) in the surroundings of thetown Halle (‘Zaschwitz’). Both sites were studied in spring 2009. The spawning waters in Zaschwitzare separated by a country road (L 156). The pond Kreuzer Teich borders, however, on two more pondswhich are all interconnected.In total, 478 migrating toads (Kreuzer Teich) versus 464 individuals (Zaschwitz) were caught. Fromthis set, individual ages of 126 (Kreuzer Teich) vs. 128 (Zaschwitz) toads were determined by using theskeletochronology method.Populations differed only slightly in morphometric parameters, but the (spring) migration period inZaschwitz was delayed in time (two days) and prolonged (ten versus six days). This might be an effect oflower air temperatures in the agricultural landscape (Zaschwitz) or, vice versa, higher city temperatures(Kreuzer Teich).Data regarding the age structure suggest that the Kreuzer Teich offers the better habitat conditions. Butthe high condition indexes show that both populations are well adapted to their living conditions.Key words: Amphibia, spring migration, morphometry, population age structure, skeletochronologymethod , habitat conditions