Differential use of trophic resources between an exotic and a coexisting native snail

ALTIERI PAULA; PAZ LAURA ESTEFANIA; FERREIRA ANA CLARA; COLPO, KARINE D.; RODRIGUES CAPITULO, ALBERTO; JENSEN ROBERTO; COSTA VLADMIR E; OCON CAROLINA

LIMNOLOGY

SPRINGER TOKYO

Lugar: Tokyo; Año: 2021 p. 1 - 8

1439-8621

Knowing the interactions between exotic and native species is essential to establishpossible threats to the local fauna. In this study, we assessed the use of foodresources and diet overlap between a recently introduced snail, Sinotaia quadrata,and a native species, Pomacea canaliculata. We analyzed the gut content and stableisotope of snails and resources in a lowland stream where both species coexist. BothSchoener´s and isotope dietary overlap indexes supported dietary overlap. Conversely,gut content analysis showed differences in consumption: S. quadrata consumed moredetritus and diatoms than P. canaliculata, whose diet was characterized by detritusand macrophyte remains. Macrophytes were the resource that most contributed to thediet of both species, as shown by stable isotope mixing models. The combination ofboth techniques, gut content and stable isotope analysis, indicated that S. quadrataconsumed macrophyte detritus while P. canaliculata ate fresh macrophytes. Thisdifference indicates differential use of food resources between the studied speciescoexisting in a lowland stream. Although no negative trophic interaction was found, wehighlight the importance of continuing to monitor interactions for other resources andstudying possible risks to the local fauna