Spatial and temporal patterns of richness and abundance in the anuran assemblage of an artificial water reservoir from the semiarid central region of Argentina

Abstract

This constitutes the first study of anuran fauna composition of an artificial permanent water reservoir, in a semiarid ecosystem of San Luis. Species richness, relative abundance, spatial distribution and pattern of summer activity were estimated in the anuran community of the Embalse La Florida, an artificial water reservoir in the semiarid central region of the sierras of San Luis, Argentina. This reservoir represents one of the few sources of water available for reproduction and early development of amphibian species in the zone. We identified anurans using call surveys during two summers at fifteen sites, belonging to four zones around the shorelines of the reservoir. Eight amphibian species (Rhinella arenarum, Melanophryniscus stelzneri, Leptodactylus bufonius, Leptodactylus mystacinus, Odontophrynus americanus, Odontophrynus occidentalis, Pleurodema tucumanum and Hypsiboas cordobae) were recorded at the shores of the embalse. The highest species richness (seven) was detected in the preserve located on the north shore. Species richness analyzed by month or survey was not correlated with weather variables. The highest relative abundance of anurans was detected at the highly modified campsites area, which may provide stable food and refugia. Relative abundance of all anuran species was positively correlated with precipitation. This permanent water reservoir may act as an important site of amphibian fauna concentration, which is important to monitor and preserve.

Amphibian and reptile diversity in Mt. Kalatungan Range Natural Park, Philippines

“…The high relative abundance of anurans "provides food and indicate permanent reservoir from precipitation" (Jofre et al 2010) since these species prefer wet habitats. In addition, amphibians and reptiles are considered indicators of environmental health since they "exploit a wide range of microhabitat and occupies wide range of tropic niches, from small invertebrate feeders through large mammal predators" (Klemens, Thorbjarnarson 1995).…”

Lead and cadmium accumulation in anuran amphibians of a permanent water body in arid Midwestern Argentina

“…A variety of factors determines the accumulation of any contaminant into an organism, including diet, habitat use, duration of exposure, and individual physiological traits (Freda 1991;Sparling and Lowe 1996). R. arenarum has long reproductive cycles, in some regions breeding opportunistically almost year-round and has been registered vocalizing in La Florida for longer periods than L. mystacinus (Jofré et al 2010;Leynaud et al 2006;Vaira 2002). The first species, therefore, might be more exposed to metal contamination either from the water or food.…”

“…Some differences in metal concentrations between species, metals, and individuals collected on shores of the embalse with different impact of contamination, were detected. More studies, tending to answer the real effect of contaminants at a population level are needed in order to adequately protect amphibians in this ecosystem that is experiencing an accelerated urban growth and human impact and holds the highest richness of anuran amphibians detected in the semiarid region of San Luis (Jofré et al 2010).…”

“…Dry environments challenge amphibians and therefore natural or artificial water reservoirs in these regions are important to the ecology of these species (Jofré et al 2010). The Embalse La Florida is an artificial lake, built 60 years ago, situated within a mountain system that divides the San Luis province (Argentina) longitudinally into a dry region to the west, and more humid regions to the east (Fig.…”

“…1). This water reservoir is an important site for amphibians, because it is one of the few sources of permanent water available for reproduction and early development of eight anuran species described to date in this semi-desert area of the Argentinean Midwest (Jofré et al 2010). The majority of the anuran species from Embalse La Florida are categorized as not threatened and with stable population trends (Lavilla 2008).…”