Diversity, spatiotemporal distribution and calling daily time in anurans (Amphibia, Anura) of an ecotonal area in North-Eastern Argentina

ABSTRACT

Studies on diversity and natural history of anuran communities are basic to distinguish natural fluctuations from those due to human impacts (a key tool in conservation programs), to assess the role they play in ecosystems dynamics and to allow comparison of diversity gradients. With those objectives, this paper analyzes diversity, temporal and spatial distribution, and calling daily time of the anurans from three breeding sites at Esteros del Iberá, in northeastern Argentina. Samples were taken monthly, between July 2008 and June 2010. We recorded 26 species belonging to five families: Bufonidae (2), Hylidae (11), Leptodactylidae (11), Microhylidae (1) and Odontophrynidae (1). The study highlights variations in species richness per site, in the period, frequency and calling daily time and in the densities of calling males. The species richness is comparable to that of other similar wetlands, including the dominance of leptodactylids and hylid, a frequent pattern in Neotropical assemblages. The concentration of active species in the warmest and wettest months was associated with changes in temperature and rainfall, which were identified as important factors that initiate reproductive activity in seasonal environments.

KEYWORDS
Natural history; amphibians; advertisement calls; reproduction; Iberá