SavedAdd your journal

Journals / Marine and Life Sciences / 2025 / Cilt: 7 Sayı: 2

Three and a half decade analysis of fish biodiversity in İzmir Bay, western Aegean Sea: Insights into fishing methods and habitat changes

Batı Ege Denizi'ndeki İzmir Körfezi'nde balık biyolojik çeşitliliğinin otuz beş yıllık analizi: Balıkçılık yöntemleri ve habitat değişikliklerine ilişkin görüler

Şule Gürkan(EGE ÜNİVERSİTESİ)0000-0003-4365-4920
Bahar Bayhan(EGE ÜNİVERSİTESİ, SU ÜRÜNLERİ FAKÜLTESİ, SU ÜRÜNLERİ PR.)0000-0003-2807-7512
Ertan Taşkavak(EGE ÜNİVERSİTESİ)0000-0001-8949-1827
Pages
110–116
Publication Date
2025-12-30
🏛️Bibliographic metadata and full text access for this article are provided via DergiPark.
DergiPark Record ↗
✨

AI Summary & Key Takeaways

AI Insight
⚡ TL;DR(Too Long; Didn't Read)

These data offer significant recommendations for sustainable fishery and species diversity management in İzmir Bay.

📌 3 Key Takeaways

🎯
Objective & Hypothesis:This study evaluates the biodiversity of fish species caught using different fishing methods in relation to habitat distribution, based on 34 length-weight studies conducted in İzmir Bay between 1990-2024.
📊
Key Findings & Data:In the study, data from 170,466 fish specimens belonging to 139 species were analyzed using the Biodiversity Pro program.
💡
Conclusion & Impact:These data offer significant recommendations for sustainable fishery and species diversity management in İzmir Bay.
🔬Design:Araştırma Makalesi
📍Scope:2024 Verileri
⚙️Variables:Biyoçeşitlilik · Balık populasyonları · Avcılık metodu

Abstract

This study evaluates the biodiversity of fish species caught using different fishing methods in relation to habitat distribution, based on 34 length-weight studies conducted in İzmir Bay between 1990-2024. The obtained data has been analysed in terms of traditional and modern fishing methods' species distributions in coastal and offshore habitats and the state of the bay ecosystem. This study examines how fish species diversity in the bay fluctuates over time, analyzing the impact of habitat characteristics and fishing practices on these variations. In the study, data from 170,466 fish specimens belonging to 139 species were analyzed using the Biodiversity Pro program. According to Simpson’s Reciprocal Index analysis, trawling is the most dominant fishing method with 20.81% in terms of number of individuals, followed by trammel net with 13.12%. While trawling, the bay's most effective fishing gear, catches 97 species, trammel net catches 28 species. The fishing method capturing the least number of individuals is fishnet with 1%. According to life forms, demersal species constitute the dominant group (18.157%) in the bay, while bathypelagic species showed the lowest diversity (1%). According to the Margalef index, the highest species richness was observed in demersal species (M: 28.265), while the lowest was in bathydemersal species (M: 43.792). According to studies between 1990-2024, fish populations with a b value above 3 comprise 68.61% in İzmir Bay. The average b value of 3.078 indicates that fish populations in the bay consist of species prone to positive allometric growth. The findings provide important contributions to understanding the ecological preferences of fishing methods and fish species. These data offer significant recommendations for sustainable fishery and species diversity management in İzmir Bay.

Özet

Bu çalışma, 1990-2024 yılları arasında İzmir Körfezi'nde gerçekleştirilen 34 adet boy-ağırlık çalışmasına dayanarak, farklı balıkçılık yöntemleriyle avlanan balık türlerinin biyolojik çeşitliliğini habitat dağılımı ile ilişkili olarak değerlendirmektedir. Elde edilen veriler, geleneksel ve modern balıkçılık yöntemlerinin kıyı ve açık deniz habitatlarındaki tür dağılımları ve körfez ekosisteminin durumu açısından analiz edilmiştir. Bu çalışma, körfezdeki balık türlerinin çeşitliliğinin zaman içinde nasıl değiştiğini inceleyerek, habitat özelliklerinin ve balıkçılık uygulamalarının bu değişiklikler üzerindeki etkisini analiz etmektedir. Çalışmada, 139 türe ait 170.466 balık örneğinin verileri Biodiversity Pro programı kullanılarak analiz edilmiştir. Simpson'ın Karşılıklı Endeks analizine göre, trol balıkçılığı, birey sayısı açısından %20,81 ile en baskın balıkçılık yöntemidir ve onu %13,12 ile tramell ağ izlemektedir. Körfezin en etkili balıkçılık aracı olan trol balıkçılığı 97 tür yakalarken, tramell ağ 28 tür yakalamaktadır. En az birey yakalayan balıkçılık yöntemi ise %1 ile balık ağıdır. Yaşam formlarına göre, demersal türler körfezde baskın grubu oluştururken (%18,157), batipelajik türler en düşük çeşitliliği göstermiştir (%1 Margalef indeksine göre, en yüksek tür zenginliği demersal türlerde (M: 28,265) gözlemlenirken, en düşük tür zenginliği batidemersal türlerde (M: 43,792) gözlemlenmiştir. 1990-2024 yılları arasında yapılan çalışmalara göre, İzmir Körfezi'nde b değeri 3'ün üzerinde olan balık popülasyonları %68,61'i oluşturmaktadır. 3,078 olan ortalama b değeri, körfezdeki balık popülasyonlarının pozitif allometrik büyümeye eğilimli türlerden oluştuğunu göstermektedir. Bu bulgular, balıkçılık yöntemlerinin ve balık türlerinin ekolojik tercihlerini anlamaya önemli katkılar sağlamaktadır. Bu veriler, İzmir Körfezi'nde sürdürülebilir balıkçılık ve tür çeşitliliği yönetimi için önemli öneriler sunmaktadır.

🔖

Cite This Article

Gürkan, Ş., Bayhan, B., Taşkavak, E. (2025). Three and a half decade analysis of fish biodiversity in İzmir Bay, western Aegean Sea: Insights into fishing methods and habitat changes. Marine and Life Sciences, Cilt: 7 Sayı: 2, 110–116. https://doi.org/10.51756/marlife.1766212

📄 Full Text PDF Viewer

📄

PDF görüntüleyici hazırlanıyor...

References (32)

  1. Akyol, O. & Perçin, F. (2005). An investigation on fishes, which are marketing in Izmir fish market between 1993 and 2004. Ege Journal of Fisheries and Aquatic Sciences, 22(1-2), 125-128.
  2. Akyol, O., Çoker, T., & Perçin, F. (2011). The very rare and little-known fishes along the coasts of Izmir (Aegean Sea, Turkey) in the past 40 years (1969–2008), Journal of Applied Ichthyology, 27(6), 1337-1345. https://doi.org/10.1111/j.1439-0426.2011.01768.x
  3. Bilecenoğlu, M. (2024). Diversity of fishes along the coast of Türkiye. Turkish Journal of Zoology, 48(6), 589-616. https://doi.org/10.55730/1300-0179.3197
  4. Cihangir, B., Ünlüoğlu, A., & Tıraşın, E. M. (2004). Analysis of the catch and diversity of the demersal fishes from the bottom trawl catches in the Izmir bay between 1997 and 2003. Turkish Journal of Aquatic Life, 2, 85-93.
  5. Crowder, L. B., Hazen, E. L., Avissar, N., Bjorkland, R., Latanich, C., & Ogburn, M. B. (2008). The impacts of fisheries on marine ecosystems and the transition to ecosystem-based management. Annual Review of Ecology, Evolution, and Systematics, 39(1), 259-278. https://doi.org/10.1146/annurev.ecolsys.39.110707.173406
  6. Depestele, J., Courtens, W., Degraer, S., Haelters, J., Hostens, K., Houziaux, J. S., Merckx, B., Polet, H., Rabaut, M., Stienen, E. W. M., Vandendriessche, S., Verfaillie, E., & Vincx, M. (2012). An integrated impact assessment of trammel net and beam trawl fisheries "WAKO II" - Final Report. Brussels: Belgian Science Policy Office, 233p (Research Programme Science for a Sustainable Development).
  7. Dunn, D. C., Boustany, A. M., & Halpin, P.N. (2011). Spatio-temporal management of fisheries to reduce by-catch and increase fishing selectivity, Fish and Fisheries, 12 (1), 110-119. https://doi.org/10.1111/j.1467-2979.2010.00388.x
  8. Gamito, S. (2010). Caution is needed when applying Margalef diversity index, Ecological Indicators, 10(2), 550-551. https://doi.org/10.1016/j.ecolind.2009.07.006
  9. Gomes, I., Erzini, K., & McClanahan, T. R. (2014). Trap modification opens new gates to achieve sustainable coral reef fisheries. Aquatic Conservation, 24(5), 680-695. https://doi.org/10.1002/aqc.2389
  10. Gündoğdu, G., Baylan, M., & Çevik, C. (2016). Comparative study of the length-weight relationships of some fish species along the Turkish Coasts. Mediterranean Marine Science, 17(1), 80-108. https://doi.org/10.12681/mms.1280
  11. Güreşen, A., Okudan, E. Ş., Aktan, Y., Erduğan, H., Dural, B., & Aysel, V. (2015). An updated checklist of marine flora on the continental shelf of Gökçeada island (northern Aegean Sea, Turkey). Journal of Aquaculture Engineering and Fisheries Research, 3(4), 171-187. https://doi.org/10.3153/JAEFR17020
  12. Holmlund, C. M., & Hammer, M. (1999). Ecosystem services generated by fish populations. Ecological Economics, 29(2), 253-268. https://doi.org/10.1016/S0921-8009(99)00015-4
  13. Jennings, S. (2005) Indicators to support an ecosystem approach to fisheries, Fish and Fisheries, 6(3), 212-232. https://doi.org/10.1111/j.1467-2979.2005.00189.x
  14. Kara, A., & Sağlam, C. (2017). İzmir Balıkçılığı: Av araçları ve Yöntemler. In: Kınacıgil, T., Tosunoğlu, Z., Çaklı, Ş., & Öztürk, H. (eds) İzmir Balıkçılığı İBB Su Ürünleri Hali Şube Müdürlüğü, 303 s. İzmir
  15. King, K. B., Giacomini, H. C., Wehrly, K., López‐Fernández, H., Thomer, A. K., & Alofs, K. M. (2023). Using historical catch data to evaluate predicted changes in fish relative abundance in response to a warming climate. Ecography, 2023(8), e06798. https://doi.org/10.1111/ecog.06798
  16. Maravelias, C. D., & Papaconstantinou, C. (2006). Geographic, seasonal and bathymetric distribution of demersal fish species in the eastern Mediterranean. Journal of Applied Ichthyology, 22(1), 35-42. https://doi.org/10.1111/j.1439-0426.2006.00695.x
  17. Pankhurst, N. W., & Munday, P. L. (2011). Effects of climate change on fish reproduction and early life history stages. Marine and Freshwater Research, 62(9), 1015-1026. https://doi.org/10.1071/MF10269
  18. Petihakis, G., Tsiaras, K., Triantafyllou, G., Kalaroni, S., & Pollani, A. (2014). Sensitivity of the N. AEGEAN SEA ecosystem to Black Sea Water inputs. Mediterranean Marine Science, 15(4), 790-804. https://doi.org/10.12681/mms.955
  19. Pielou, E. C. (1975). Ecological diversity, John Wiley and Sons, New York 165 pp.
  20. Sadler, D. E., Watts, P. C., & Uusi-Heikkilä, S. (2023). The riddle of how fisheries influence genetic diversity. Fishes, 8(10), 510. https://doi.org/10.3390/fishes8100510
  21. Şenbahar, A. M., Güleç, Ö., & Tosunoğlu, Z. (2020). Species diversity and dominancy indexes in Izmir Bay (Aegean Sea) purse seine fishery. Ege Journal of Fisheries and Aquatic Sciences, 37(4), 353-356. https://doi.org/10.12714/egejfas.37.4.05
  22. Simpson, E. H. (1949). Measurement of diversity. Nature, 163(4148), 688. https://doi.org/10.1038/163688a0
  23. Talas, E., Duman, M., Eronat, A. H., & Küçüksezgin, F. (2023). Multi-index assessment of sea bottom sediments of the Izmir Gulf, Aegean Sea: A study of interrelation between anthropogenic and hydrodynamic effects. Marine Pollution Bulletin, 194, 115293. https://doi.org/10.1016/j.marpolbul.2023.115293
  24. Tesch, F. (1968). Age and growth. In: Ricker W. (Eds).Methods for assessment of fish production in fresh waters. (pp. 93-123) Blackwell Scientific Publications, Oxford.
  25. Tunca, S., Sánchez Lizaso, J. L., & Ünal, V. (2022). A stakeholder analysis of the artificial reefs in Edremit Bay, Turkey: Social, economics, and management aspects. In Ramos J. H. P. (Ed.), Impact of Artificial Reefs on the Environment and Communities (pp. 48-66). IGI Global.
  26. Ulman, A., Zengin, M., Demirel, N., & Pauly, D, (2020). The lost fish of Türkiye: a recent history of disappeared species and commercial fishery extinctions for the Turkish Marmara and Black Seas. Frontiers Marine Science, 7, 650. https://doi.org/10.3389/fmars.2020.00650
  27. van Overzee, H. M. J., & Rijnsdorp, A.D. (2015). Effects of fishing during the spawning period: Implications for sustainable management. Reviews in Fish Biology and Fisheries, 25(1), 65-83. https://doi.org/10.1007/s11160-014-9370-x
  28. Winemiller, K. O. (2005). Life history strategies, population regulation, and implications for fisheries management. Canadian Journal of Fisheries and Aquatic Sciences, 62(4), 872-885. https://doi.org/10.1139/f05-040
  29. Winemiller, K. O., & Rose, K. A. (1992). Patterns of life-history diversification in North American fishes: implications for population regulation. Canadian Journal of Fisheries and Aquatic Sciences, 49(10), 2196-2218. https://doi.org/10.1139/f92-242
  30. Wijermans, N., Boonstra, W. J., Orach, K., Hentati‐Sundberg, J., & Schlüter, M. (2020). Behavioural diversity in fishing-Towards a next generation of fishery models. Fish and Fisheries, 21(5), 872-890. https://doi.org/10.1111/faf.12466
  31. Wootton, R. J. (1990). Ecology of teleost fishes, Springer, 404 pp.
  32. Wright, P. J., & Trippel, E. A. (2009). Fishery‐induced demographic changes in the timing of spawning: consequences for reproductive success. Fish and Fisheries, 10(3), 283-304. https://doi.org/10.1111/j.1467-2979.2008.00322.x