Comparison of fish prey contribution in the diet of European hake by visual assessment of stomach contents and DNA metabarcoding

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Gül G., Keskin E., Demirel N.

Environmental Biology of Fishes, vol.106, no.4, pp.613-625, 2023 (SCI-Expanded) identifier

  • Publication Type: Article / Article
  • Volume: 106 Issue: 4
  • Publication Date: 2023
  • Doi Number: 10.1007/s10641-023-01398-x
  • Journal Name: Environmental Biology of Fishes
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus, PASCAL, Animal Behavior Abstracts, Aqualine, Aquatic Science & Fisheries Abstracts (ASFA), BIOSIS, CAB Abstracts, Environment Index, Geobase, Veterinary Science Database
  • Page Numbers: pp.613-625
  • Keywords: Fish prey, Merluccius merluccius, Next generation sequencing, Sea of Marmara, Seasonal shift
  • Istanbul University Affiliated: Yes


Diet studies are critical for ecosystem-level understanding of fish populations and a move toward ecosystem-based management of marine resources. European hake, Merluccius merluccius, a demersal mesopredator species, is one of the most important commercial fish in the Mediterranean, and as a predatory species it controls the food web. Here, we characterize the diet of M. merluccius with two different analytical methods, visual assessment of stomach contents and DNA metabarcoding. Seasonal and size-based differences in fish prey composition were investigated. Both methods produced complementary results with regard to fish prey contribution of European hake diet. The visual assessment approach showed significant differences between adult and juvenile hakes, while the metabarcoding approach indicated high seasonality in fish prey contribution and richness in its diet. An increase in fish prey diversity was found for both adult and juvenile hakes during the summer. Trachurus sp. was detected as the dominant fish prey in both methods. A broader range of fish prey species was detected by metabarcoding due to its ability to identify highly digested items from the stomach. Combining visual assessment with a novel metabarcoding approach has the potential to improve our understanding of trophic ecology, which can be useful for ecosystem-based management.