Skip to main content
SpringerLink
Log in

Diet Composition and Reproductive Properties of European Conger, Conger conger (Congridae) in the Turkish Aegean Sea

  • Published:
Journal of Ichthyology Aims and scope Submit manuscript

Abstract

The diet composition and reproductive properties of European conger, Conger conger (Linnaeus, 1758) were investigated from the Aegean Sea of Türkiye to compare our data with those from other regions of the Mediterranean Sea and throughout all four seasons. A total of 100 individuals were examined. Totally 19 prey taxa belonging to three large taxon (cephalopods, crustaceans, and fishes) were identified in the stomachs of European conger. According to the relative significance index the crustaceans were dominant food in diet of individuals smaller than 50 cm, while fish prevailed in diet of fish with length between 75 and 100 cm. Histological analysis of 80 gonads showed that all individuals were immature (20%) and maturuing females (80%). Maturing females were with oocytes in the previtellogenic (16% of all fishes) and early vitellogenic phases (64%). The oocyte diameters were 80–476 μm at previtellogenic (diameter range 80–240 μm) and 245–476 μm at early vitellogenic individuals. Immature females had the gonads with the oocyte diameter < 30 μm.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Log in via an institution

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Institutional subscriptions

Fig. 1.
Fig. 2.
Fig. 3.

Similar content being viewed by others

REFERENCES

  1. Abi-Ayad, S.M.E.A., Kerfouf, S.A., Mehidi Saddikioui, S., and Talet, A.B.T., Donnees Preliminaires Sur la Composition du Régime Alimentaire du Congre (Conger conger Linanaeus, 1758) de la Côte Occidentale Algérienne, Eur. J. Sci. Res., 2011, vol. 64, no. 2, pp. 314−324. https://doi.org/10.12681/mms.479

    Article  Google Scholar 

  2. Amundsen, P.A, Sánchez-Hernández, J., Feeding studies take guts—critical review and recommendations of methods for stomach contents analysis in fish, J. Fish. Biol., 2019, vol. 95, pp. 1364–1373. https://doi.org/10.1111/jfb.14151

    Article  PubMed  Google Scholar 

  3. Anastasopoulou, A., Mytilineou, C.H., Lefkaditou, E., et al., The diet and feeding ecology of Conger conger (L. 1758) in the deep waters of the Eastern Ionian Sea, Mediterr. Mar. Sci., 2013, vol. 14, no.2, pp. 365−368. https://doi.org/10.12681/mms.479

    Article  Google Scholar 

  4. Bagenal, T.B., and Tesch, F.W., Age and growth, in Methods for Assessment of Fish Production in Fresh Waters, Oxford: Blackwell Sci. Publ., 1978, pp. 101−136.

    Google Scholar 

  5. Bauchot, M.L., and Saldanha, L., Congridae, in Fishes of the North-Western Atlantic and the Mediterranean, P.J.P. Whitehead, Eds., Paris: UNESCO, 1986, vol. 2, pp. 567–574.

    Google Scholar 

  6. Bell, J.D., and Harmelin-Vivien, M.L., Fish fauna of French Mediterranean Posidonia oceanica seagrass meadows, 2. Feeding Habits, Tethys, 1983, vol. 11, no. 1, pp. 1–14.

    Google Scholar 

  7. Berg, J., Discussion of methods of investigating the food of fishes, with reference to a preliminary study of the food of Gobiusculus flavescens (Gobiidae), Mar Biol., 1979, vol. 50, pp. 263−273.

    Article  Google Scholar 

  8. Bilecenoğlu, M., Kaya, M., Cihangir, B., and Çiçek, E., An updated checklist of the marine fishes of Turkey, Turk. J. Zool., 2014, vol. 38, pp. 901−929. https://doi.org/10.3906/zoo-1405-60

    Article  Google Scholar 

  9. Cau, A., and Manconi, P., Relationship of feeding, reproductive cycle and bathymetric distribution in Conger conger, Mar. Biol., 1984, vol. 81, no. 2, pp. 147−151.

    Article  Google Scholar 

  10. Correia, A.T., Mansoa, S., and Coimbraa, J., Age, growth and reproductive biology of the European conger eel (Conger conger) from the Atlantic Iberian waters, Fish. Res., 2009, no. 99, pp. 196–202. https://doi.org/10.1016/j.fishres.2009.06.002

  11. Fannon, E., Fahy, E., and O’reilly, R., Maturation in female conger eel, Conger conger (L.), J. Fish Biol., 1990, vol. 36, no. 2, pp. 275−276.

    Article  Google Scholar 

  12. Froese, R., and Pauly, D., Fish Base, Version 07/2022. http://www.fishbase.org.

  13. Gomes, T.M., Sola, E., Gros, M.P., et al., Trophic relationships and feeding habits of demersal fishes from the Azores: Importance to multispecies assessment, J. Mar. Res., 1998, vol. 35, pp. 7–21.

    Google Scholar 

  14. Grandcourt, E.M., Al Abdessalam, T.Z., Francis, F., et al., Reproductive biology and implications for management of the orange-spotted grouper Epinephelus coioides in the southern Arabian Gulf, J. Fish Biol., 2009, vol. 74, pp. 820–841. https://doi.org/10.1111/j.1095-8649.2008.02163.x

    Article  CAS  PubMed  Google Scholar 

  15. Holden, M.J., and Raitt, D.F.S., Manual of Fisheries Science, Part 2: Methods of Resource İnvestigation and Their Application, Rome: FAO, 1974.

  16. Hyslop, E.J., Stomach contents analysis—a review of methods and their application, J. Fish Biol., 1980, vol. 17, pp. 411−429.

    Article  Google Scholar 

  17. Karachle, P.K., Diet composition and overlap for 43 fishes in the North Aegean Sea, Greece, Acta Adriat., 2017, vol. 58, no. 1, pp. 125− 136. https://doi.org/10.32582/aa.58.1.10

    Article  Google Scholar 

  18. Karachle, P.K., Stergiou, K.I., Trophic levels of North Aegean sea fishes, Fishes in Databases and Ecosystems, vol. 14, no. 4, Fish. Centre Res. Rep., 2006, pp. 22−26.

  19. Karataş, A., Filiz, H., Erciyas-Yavuz, K., et al., The Vertebrate Biodiversity of Turkey, in Biodiversity, Conservation and Sustainability in Asia, M. Öztürk et al., Eds., Springer, 2021, vol. 10, pp. 175−274. https://doi.org/10.1007/978-3-030-59928-7_10

  20. Macpherson, E., Resource partitioning in a Mediterranean demersal fish community, Mar. Ecol. Prog. Ser., 1981, vol. 4, pp. 183−193.

    Article  Google Scholar 

  21. Maigret, J., and Ly, B., Les poissons de mer de Mauritanie, Compiègne: Sci. Nat., 1986.

    Google Scholar 

  22. Matić-Skoko, S., Ferri, F.J., Tutman, P., et al., The age, growth and feeding habits of the European conger eel, Conger conger (L.) in the Adriatic Sea, Mar. Biol. Res., 2012, vol. 8, no. 10, pp. 1012−1018. https://doi.org/10.1080/17451000.2012.706307

    Article  Google Scholar 

  23. Mazouz, M., and Abi-Ayad, S.M.E.A., Contribution to the study of reproduction parameters of the European Conger eel (Conger conger; Linnaeus, 1758) from the western Algerian Coasts, Oran Bay (Algeria), Int. J. Sci. Technol. Res., 2015, vol. 4, no. 9, pp. 209−214.

    Google Scholar 

  24. Mazouz, M., Seddikoui, L., Bensahla Talet, A., and Abi-Ayad, S.M.E.A., Some aspects of the reproductive cycle of the European conger eel, Conger conger (Linnaeus, 1758) (Osteichthyes, Anguilliformes, Congridae) captured from Western Algerian coasts: a histological description of oogenesis, Sylwan, 2014, vol. 158, no. 7, pp. 2−13.

    Google Scholar 

  25. Morato, T.M., Sola, E., Gros, M.P., et al., Trophic relationships and feeding habits of demersal fishes from the Azores: Importance to multispecies assessment, International Council for the Exploration of the Sea, ICES CM 1998/O 7, 1998.

  26. Morato, T., Solà, E., Gros, M.P., and Menezes, G., Diets of forkbeard (Phycis phycis) and conger eel (Conger conger) of the Azores during spring of 1996 and 1997, Life Mar. Sci., 1999, vol. 17, no. pp. 51−64.

  27. Mytilineou, C., Politou, C.Y., Papaconstantinou, C., et al., Deep-water fish fauna in the Eastern Ionian Sea, Belg. J. Zool., 2005, vol. 135, pp. 229−233.

    Google Scholar 

  28. Olaso, I., and Rodrigues-Marin, E., Alimentatión de veinte especies de peces demersales pertenecientes a la división VIIIc del ICES. Otoño 1991, Informes Técnicos Instituto Español de Oceanografia, 1995, vol. 157.

    Google Scholar 

  29. O’Sullivan, S., Moriarty, C., Fitzgerald, R.D., et al., Age, growth and reproductive status of the European conger eel, Conger conger (L.) in Irish coastal waters, Fish. Res., 2003, vol. 64, pp. 55–69. https://doi.org/10.1016/S0165-7836(03)00100-0

    Article  Google Scholar 

  30. O’Sullivan, S., Moriarty, C., and Davenport, J., Analysis of the stomach contents of the European conger eel Conger conger in Irish waters, J. Mar. Biol. Assoc. UK, 2004, vol. 84, pp. 823−826. https://doi.org/10.1017/S0025315404010008h

    Article  Google Scholar 

  31. Robinet, T., Sbaihi, M., Guyet, S., et al., Advanced sexual maturation before marine migration of Anguilla bicolour and Anguilla marmorata at Reunion Island, J. Fish. Biol., 2003, vol. 63, pp. 538− 542. https://doi.org/10.1046/j.1095?8649.2003.00165.x

    Article  Google Scholar 

  32. Sallami, S.A., Majoka, M.A., Saha, S.et al., Efficacy of dietary antioxidants on broiler oxidative stress, performance and meat quality: Science and market, Avian Biol. Res., 2015, vol. 8, pp. 65–78. https://doi.org/10.3184/175815515X14291701859483

    Article  Google Scholar 

  33. Sbaihi, M., Fouchereau-Peron, M., Meunier, F., et al., Reproductive biology of conger eel from the south coast of Brittany, France and comparison with the European eel, J. Fish. Biol., 2001, vol. 59, pp. 302−318. https://doi.org/10.1111/j.1095?8649.2001.tb00131.x

    Article  CAS  Google Scholar 

  34. Stergiou, K.I., and Karpouzoi, V., Feeding habits and trophic levels of Mediterranean fish, Rev. Fish Biol. Fisheries, 2002, vol. 11, pp. 217–254. https://doi.org/10.1023/A:1020556722822

    Article  Google Scholar 

  35. Tosunoglu, Z., Trawl codend design (44 mm diamond PE mesh) and the effect on selectivity for Pagellus erythrinus and Pagellus acarne, two species with different morphometrics, J. Appl. Ichthyol., 2007, vol. 23, pp. 578–582.

    Article  Google Scholar 

  36. Vallisneri, M., Scapolatempo, M., Manfredi, C., and Tommasini, S., Osservazioni sulla distribuzione e biologia del grongo (Conger conger L.) in Alto-Medio Adriatico, Biol. Mar. Mediterr., 2007, vol. 13, no. 1, pp. 920−923.

    Google Scholar 

  37. Xavier, J.C., Cherel, Y., Assis, C.A., et al., Feeding ecology of conger eels (Conger conger) in north-east Atlantic waters, J. Mar. Biol. Assoc. UK, 2010, vol. 90, no. 3, pp. 493−501. https://doi.org/10.1017/S0025315409990555

    Article  Google Scholar 

Download references

ACKNOWLEDGMENTS

The authors would like to thank the project staff for their help in field studies. The authors also thank the two anonymous referees for their valuable comments and suggestions.

Funding

The study was carried out with the financial support of the Ege University Scientific Research Project (2015/SUF/002), İzmir, Türkiye.

Author information

Authors and Affiliations

  1. Ege University Faculty of Fisheries Department of Hydrobiology, İzmir, Türkiye

    B. Bayhan & B. Taylan

Authors
  1. B. Bayhan
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. B. Taylan
    View author publications

    You can also search for this author in PubMed Google Scholar

Corresponding author

Correspondence to B. Taylan.

Ethics declarations

Conflict of interests. The author declares that he has no conflicts of interest.

Statement on the welfare of humans or animals. All applicable international, national, and/or institutional guidelines for the care and use of animals were followed.

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Bayhan, B., Taylan, B. Diet Composition and Reproductive Properties of European Conger, Conger conger (Congridae) in the Turkish Aegean Sea. J. Ichthyol. 63, 524–533 (2023). https://doi.org/10.1134/S0032945223030025

Download citation

  • Received:

  • Revised:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1134/S0032945223030025

Keywords:

Search

Navigation