Results of the first analysis of tadpoles’ diet and determination of microplastics presence of Rana, Bufo and Bufotes species from different localities in Serbia

Abstract

Nutrition is one of the main processes in living beings because it provides energy. Amphibians are an essential link in food chains, but they have not been sufficiently studied. It is believed that most anuran larvae and tadpoles are omnivorous, but the trophic status of many tadpoles has not been precisely determined. Microplastics (MPs) are one of the major threats to aquatic ecosystems and can be ingested by various groups of aquatic organisms, such as plankton, shellfish, fish, and amphibians, but current knowledge of MPs occurrence in these aquatic organisms is still scarce. In this research, the intestinal contents of tadpoles of four anuran species were analyzed to assess nutrition and the presence of microplastics. The results show that the largest percentage of tadpoles’ diet consists of diatoms from the genera Achnanthidium and Navicula, and detritus. The remains of some invertebrates were also present in the material. Microplastic analysis proved the presence of MPs in all investigated samples. The data obtained in this research represent the first concrete results due to which it is necessary to continue extensive research at several levels.

Ishrana je jedan od ključnih procesa živih bića jer predstavlja glavni izvor energije. Vodozemci su važna karika u lancima ishrane, ali nisu dovoljno proučavani. Veruje se da je većina larvi bezrepih vodozemaca, odnosno punoglavaca, omnivorna, ali trofički status mnogih punoglavaca nije precizno utvrđen. Mikroplastika (MP) je jedan od glavnih zagađivača u vodenim ekosistemima pa je različite grupe vodenih organizama, kao što su plankton, školjke, ribe i vodozemci mogu uneti u organizam, ali trenutno znanje o prisustvu MP u ovim vodenim organizmima je još uvek nedovoljno. U ovom istraživanju analiziran je sadržaj creva punoglavaca četiri vrste bezrepih vodozemaca kako bi se procenila ishrana i prisustvo mikroplastike. Rezultati pokazuju da najveći procenat ishrane punoglavaca čine silikatne alge iz rodova Achnanthidium i Navicula, kao i detritus. Takođe, u sadržaju creva bili su prisutni i ostaci nekih beskičmenjaka. Analize mikroplastike dokazale su da su čestice MP prisutne u svim ispitivanim uzorcima. Podaci dobijeni u ovom istraživanju predstavljaju prve konkretne rezultate zbog kojih je neophodno nastaviti dodatna istraživanja na više nivoa