Discovering hidden biodiversity: The use of complementary monitoring of fish diet based on DNA barcoding in freshwater ecosystems

Research output: Working paperResearch

  • Hyunbin Jo, Korea, Republic of
  • Marc Ventura, Centre for Advanced Studies of Blanes (CEAB), Spain
  • Nicolas Vidal
  • ,
  • Jeong-Soo Gim, Korea, Republic of
  • Teresa Buchaca, Denmark
  • Leon Barmuta, School of Biological Sciences, University of Tasmania, Australia
  • Erik Jeppesen
  • Gea-Jae Joo, Department of Biological Sciences, Pusan National University, Korea, Republic of
Ecological monitoring contributes to the understanding of complex ecosystem functions. The diets of fish reflect the surrounding environment and habitats and may, therefore, act as useful integrating indicators of environmental status. It is, however, often difficult to visually identify items in gut contents to species level due to digestion of soft-bodied prey beyond visual recognition, but new tools rendering this possible are now becoming available. We used a molecular approach to determine the species identities of consumed diet items of an introduced generalist feeder, brown trout (Salmo trutta), in 10 Tasmanian lakes and compared the results with those obtained from visual inspection of stomach contents. We obtained 44 unique taxa (OTUs) belonging to 5 phyla, including 7 classes, using the barcode of life approach from cytochrome oxidase I (COI). Compared with visual inspection, DNA analysis showed greater accuracy, yielding a 1.4-fold higher number of OTUs. Rarefaction curve analysis showed saturation of visually inspected taxa, while the curves from the DNA barcode did not saturate. The OTUs with the highest proportions of haplotypes were the families of terrestrial insects Formicidae, Chrysomelidae and Torbidae and the freshwater Chironomidae. The haplotype occurrence per lake was negatively correlated with lake depth and transparency. Nearly all haplotypes were only found in one fish gut from a single lake. Our results indicate that DNA barcoding of fish diets is a useful and complementary method for discovering hidden biodiversity.
Original languageEnglish
Publication statusPublished - 2015

See relations at Aarhus University Citationformats

ID: 89981676