The presence of Polypedates cruciger tadpoles reduces the growth of Duttaphrynus melanostictus tadpoles under laboratory conditions

Abstract

Competition is one of the main types of interactions in ecological communities. Interspecific competition of many organisms including anuran tadpoles has been demonstrated in numerous previous studies. However, a few studies have also shown that interspecific competition is absent or insignificant in certain tadpole communities. In this study, we conducted experiments to assess whether the presence of one species of tadpole affects the growth of another species. We selected tadpoles of two commonly co-occurring species of anurans in Sri Lanka: Duttaphrynus melanostictus and Polypedates cruciger. The length and width of tadpoles were used as a measure of growth. The laboratory experiments revealed that the presence of P. cruciger tadpoles negatively impacted the growth of D. melanostictus tadpoles. Tadpoles of D. melanostictus that were raised with P. cruciger tadpoles (treatment) were significantly smaller than those raised with conspecifics (control). P. cruciger tadpoles that were raised with D. melanostictus tadpoles were significantly bigger than those raised with conspecifics. We believe that these effects are due to the superiority of P. cruciger tadpoles to D. melanostictus tadpoles in terms of competition.