Reproductive activity of anurans in a dominant agricultural landscape from central-eastern Argentina

Resumen

Agriculture can modify natural systems through habitat loss and fragmentation, as well as through the effect of agrochemicals on biological traits such as reproduction. We studied anuran diversity and reproduction of assemblages from 3 sites with different degrees of agricultural activities (an agroecosystem, a transitional area, and a natural forest) located in Entre Ríos province (Argentina). We conducted several field surveys during 2 soybeancropping periods from November 2006 to April 2008. A total of 23 anuran species were identified. Richness, evenness and diversity differed among sites. No range-abundance models were statistically adequate to describe the distribution of abundances within the agroecosystem, whereas the anuran species from the other 2 sites fitted the normal logarithmic model. The location and substrates used for nuptial calling in ponds, as well as the reproductive periods of anuran species varied among sites. These findings might respond to a combination of factors, such as anuran composition, species abundances, availability of reproductive microhabitats, and variation of microclimatic characteristics among sites, the agroecosystem being the most different anuran reproductive community. Finally, our results suggest that agricultural land use have adverse effects on the reproduction of anurans in central-eastern Argentina.