Dynamics of Anuran Assemblage in a Wetland from the Southern Section of Parana river, Argentina

• Published in: Interciencia Vol. 32; no. 7; pp. 463 - 470
• Main Authors: Sanchez, L C, Peltzer, P M, Manzano, A S, Lajmanovich, R C
• Format: Journal Article
• Language: Spanish
• Published: 01.07.2007
• Subjects: Anura; Argentina, Buenos Aires, Parana R
• ISSN: 0378-1844

Diversity, composition, and size structure of anuran assemblages from the Pre-Delta National Park (PNPD) are described during one annual period. Pit fall traps were placed from Dec 2004 until Dec 2005. The relationship between richness and temperature, relative humidity, number of days with rain, precipitation, and water level of the river were analyzed through simple and partial correlation. A contingency analysis was performed for investigating the phenology of the most abundant species, contrasting for each species the monthly frequencies with the half frequency of capture throughout the year. Also, each species' frequency was compared with the cumulative frequencies of the remaining ones. Snout-vent lengths (LHC) of each anuran were analyzed each month. A total of 16 species belonging to 5 families were collected. Simple correlation coefficients showed that richness was related to temperature and water level, while partial correlation coefficients did not lead to the same results. The highest activity was observed from Jan-Apr and Nov-Dec 2005. There were significant differences in the phenology of each species. In the warm months LHC decreases were observed. It is suggested that the annual cycles in size structure could be related to recruitment times of juveniles. Finally, it is concluded that the activity patterns of the different anurans and their reproductive cycles influence the temporary structure of the studied anuran assemblage.