Comprehensive Biometric Study on the Invasive Seaweed, Caulerpa mexicana, in the Aegean Sea

Year 2025, Volume: 8 Issue: 1, 46 - 63, 14.07.2025

Erhan Mutlu , Yaşar Özvarol , Barış Akçalı , Berivan Elif Aslan , Zeynep Narlı , Zeynep Zabun

https://doi.org/10.46384/jmsf.1639055

Abstract

The present study investigates the occurrence and biometry of the invasive seaweed Caulerpa mexicana in the Gulf of İzmir, Aegean Sea, thereby highlighting its ecological implications in a region increasingly affected by biological invasions. The Mediterranean basin, especially the eastern and Aegean parts, is becoming a hotspot for non-native species, and the region may be a place of interest with the occurrence of the C. mexicana species. This research represents the first detailed assessment of its biometric characteristics in the Levant-Aegean Basin. The study's sampling was conducted from May to August 2024 at 321 stations along the Aegean coast, and C. mexicana was identified at only two specific sites. The species was found in shallow coastal waters at depths of 10 m and 15 m with densities of 630 shoots/m² and 469 shoots/m², respectively. Morphometric analysis revealed frond lengths ranging from 10 to 12.5 centimeters and widths from 7 to 9 millimeters, with a significant correlation between frond length and number of pinnae. Environmental parameters such as temperature, salinity, and dissolved oxygen were measured, providing a context for the species' habitat preferences. The findings underscore the invasive potential of C. mexicana and its capacity to perturb local marine ecosystems, highlighting the necessity for persistent monitoring and management strategies to mitigate its deleterious effects.

Keywords

Caulerpa mexicana , Non-indigenous species , invasive , biometry , Aegean Sea

Supporting Institution

TUBITAK

Project Number

124Y031

Thanks

The authors would like to express their sincere gratitude to the Scientific and Technological Research Council of Turkey (TÜBİTAK) for providing financial support through project number 124Y031. Special thanks are extended to İdil Akçalı for meticulously reviewing and controlling the English language used in the paper. The authors also wish to acknowledge the dedicated efforts and support provided by the crew of the R/V Akdeniz Su during this project.

Ege Denizi'ndeki Istilacı Deniz Yosunu Caulerpa mexicana Hakkında Kapsamlı Biyometrik Çalışma

Abstract

Mevcut çalışma, İzmir Körfezi, Ege Denizi'ndeki istilacı deniz yosunu Caulerpa mexicana'nın bulunmasını ve biyometrisini araştırarak, biyolojik istilalardan giderek daha fazla etkilenen bir bölgedeki ekolojik etkilerini vurgulamaktadır. Akdeniz havzası, özellikle doğu ve Ege kesimleri, yerli olmayan türler için bir sıcak nokta haline gelmektedir ve C. mexicana türünün görülmesi ile bölge dikkat çekebilir. Bu araştırma, Ege-Levant Havzası'ndaki biyometrik özelliklerinin ilk ayrıntılı değerlendirmesini temsil etmektedir. Çalışmanın örneklemesi Mayıs-Ağustos 2024 arasında Ege kıyısı boyunca 321 istasyonda yürütülmüş ve C. mexicana yalnızca iki belirli noktada tanımlanmıştır. Tür, sırasıyla 630 sürgün/m² ve 469 sürgün/m² yoğunlukta, 10 m ve 15 m derinlikteki sığ kıyı sularında bulunmuştur. Morfometrik analiz, yaprak uzunluklarının 10 ila 12,5 santimetre ve genişliklerinin 7 ila 9 milimetre arasında değiştiğini ve yaprak uzunluğu ile pinnae sayısı arasında önemli bir korelasyon olduğunu ortaya koydu. Sıcaklık, tuzluluk ve çözünmüş oksijen gibi çevresel parametreler ölçülerek türün habitat tercihleri için bir ilişki sağlandı. Bulgular, C. mexicana türünün istilacı potansiyelini ve yerel deniz ekosistemlerini bozma kapasitesini vurgulayarak, zararlı etkilerini azaltmak için sürekli izleme ve yönetim stratejilerinin gerekliliğini belirtmiştir.

Keywords

Caulerpa mexicana , yerli olmayan tür , istilacı , biyometri , Ege Denizi

Project Number

124Y031

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