Feeding overlap in two sympatric species of Rhinella (Anura: Bufonidae) of the Atlantic Rain Forest

Abstract

A clear understanding of the relationships between overlapping, similarity, and competition is necessary to understand many of the questions about the structure and operation of a community. Rhinella icterica (Spix, 1824) and Rhinella crucifer (Wied Neuwied, 1821) are sympatric species of toads occurring in the National Park of Serra dos Órgãos in southeastern Brazil. The aim of the present study was to assess the dietary overlap of these two species. Ninety-four stomachs were analyzed, and 2245 prey items were found. Common prey were Hymenoptera, Coleoptera, Diptera, Lepidoptera larvae, Blattaria, Orthoptera, Hemiptera, Opiliones, and Aranaea. Ants were the most important prey in both diets, followed by beetles and cockroaches. The niche breadth of R. icterica was 1.76 and of R. crucifer was 1.28. The dietary overlap between the species was 98.62%. A positive correlation was observed between jaw width and prey size consumed by R. icterica.

Diet of the toad Rhinella icterica (Anura: Bufonidae) from Atlantic Forest Highlands of southeastern Brazil

“…Also, in one stomach (5.9%) we found parts of skin of R. icterica. The occurrence of own skin in the stomachs of R. icterica has been also found in other studies regarding Rhinella species (Evans & Lampo 1996, Teixeira et al 1999, Sabagh & Carvalho-e-Silva 2008 and it seems to constitutes a common habit among amphibians, which recycle their skin during molting (Weldon et al 1993). Remains of plant material were found in 10 stomachs (58.8%).…”

“…However, most studies concentrated in the Atlantic Rain Forest (e.g. Siqueira et al 2006, Santana & Juncá 2007, Sabagh & Carvalho-e-Silva 2008, Ferreira & Teixeira 2009) involved species and populations living in lowland areas (e.g. Boquimpani-Freitas et al 2002, Siqueira et al 2006, Almeida-Gomes et al 2007, Ferreira & Teixeira 2009, Martins et al 2010, Almeida-Santos et al 2011, especially in the ombrophilous forest, with a marked lack of information on anurans feeding habits from highlands.…”

“…Some studies have investigated the relationship and influence of the size of the frog and the size of prey ingested (e.g. Sabagh & Carvalho-e-Silva 2008, Duré et al 2009, Quiroga et al 2009, Batista et al 2011, Maragno & Souza 2011 as an ontogenetic diet shift.…”

“…We used the individual-based rarefaction method (Gotelli & Colwell 2001) to validate the comparison between the richness of prey (orders) of two R. icetrica populations from PNI (data from present study) and Serra dos Órgãos National park -PARNASO (data from Sabagh & Carvalho-e-Silva 2008) even with samples being distinct sizes (Bonansea & Vaira 2007). The rarefaction curves (with standard deviation) and the Jacknife 1 richness estimator were done performing 1,000 randomizations without replacement using the software EstimateS 8.2 (Colwell 2009).…”

Lesser Grison (Galictis cuja Molina, 1782) as host of Dioctophyme renale Goeze, 1782

“…According to local studies, there is a prevalence of 5.17% of D. renale larves in Chaunus ictericus (PEDRASSANI et al, 2009), an amphibian with a wide geographic distribution. C. ictericus has an easy adaptability to modified environments and it is commonly found near human habitations (SABAGH; CARVALHO-E-SILVA, 2008).…”