Trophic ecology of two Pithecopus species (Anura: Phyllomedusidae) living in syntopy in southern Bahia, Brazil

ABSTRACT

To coexist, two species should use available resources in different ways. These differences may happen in three different dimensions: temporal, spatial and trophic. In frogs, differences in trophic dimensions are mainly due to different sizes and types of ingested prey. We studied the diet of two syntopic Pithecopus species, addressing prey selectivity and sharing of food resources. Fieldwork was undertaken at the Michelin Ecological Reserve, southern Bahia, between the years 2011 and 2012. Stomach contents were retrieved using a flushing procedure and data on prey availability was obtained. Of the 16 invertebrate categories found in the environment, 11 were consumed by P. rohdei and 12 by P. nordestinus, features that characterize a generalist diet. The most abundant category in the diet of P. nordestinus was Diptera while Hemiptera was the most consumed prey category for P. rohdei. Trophic niche overlap was high considering the size of ingested prey and lower for categories. The selectivity index showed that both species used the resources available in the environment in a slightly different way. The differences found concerning trophic ecology of these two species seem to be sufficient to allow coexistence in the studied area.

KEYWORDS:

• Prey selectivity
• diet
• feeding
• resource partitioning
• Amphibia

Acknowledgments

We thank Danilo Ruas, Caio Mendes, Yamid Mera, Paulo Ribeiro and Elis Bastos for help during fieldwork; Rofolfo Mariano, Andres Egea-Serrano, Wilian Vaz-Silva and Antônio Argôlo, Anne Zillikens and three anonymous reviewers for constructive critical comments on the manuscript.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

We are indebted to the Center for Biodiversity Studies of the Michelin Ecological Reserve for providing financial and logistic support for our research. RMO thanks CAPES for a scholarship and MS thanks CNPq for a research grant and Alexander von Humboldt Stiftung/CAPES for a scholarship.