MSc Student
Advisor: Christian Schulze

Division of Tropical Ecology and Animal Biodiversity
Department of Botany and Biodiversity Research, University of Vienna

Abstract

Tropical forests have undergone severe changes in the past century.  Many old-growth forests were cleared and supplanted with plantations and pastures, leaving behind a much-fragmented matrix of human-dominated landscapes. Loss and fragmentation of forest habitats have been shown to be major forces behind the decrease of biodiversity worldwide. Much emphasis has been placed on the importance of primary forests, while human-altered forests have often been labeled as degraded - despite their ability to self-regenerate. 19 transect sites in primary forest, secondary forest, gallery forest and pastures were selected to study the composition of amphibian communities around La Gamba in SW Costa Rica. In total, 26 species of frogs from six families (Hylidae, Craugastoridae, Leptodactylidae, Dendrobatidae, Centrolenidae and Bufonidae) and one species of salamander from the family Plethodontidae were documented. Species richness was highest in primary forest but was almost equal to secondary forest and gallery forest, while only pasture sites showed considerably diminished diversity. Species composition differed between habitat types but was most pronounced at pasture sites, where four species of frogs were documented that prefer human-altered habitats to forest. Five species of anurans were found in all habitat types. Successional forests can function as a stronghold for amphibians and ultimately increase the effective size of forest corridors such as the COBIGA biological corridor.

Keywords: amphibians, biodiversity, secondary forest, Costa Rica, rainforest, biological corridor