Fisheries Biology of Non-Indigenous Sardine, Sardinella gibboza, on the Mediterranean Sea Front Damietta Region, Egypt

El Far, Alaa; Ali, Aisha; Nawareg, Mona; Elgetany, Asmaa H; Bahnasawy, Mohamed Hamed; El-Tohamy, Wael S.

doi:10.21608/ejabf.2025.409452.6318

Fisheries Biology of Non-Indigenous Sardine, Sardinella gibboza, on the Mediterranean Sea Front Damietta Region, Egypt

Document Type : Original Article

Authors

¹ National Institute of Oceanography and Fisheries

² Marine and Coastal Water Biology Department, Faculty of Science, Zintan University, Libya

³ Zoology Department, Faculty of Science, Damietta University

⁴ Zoology Department, Faculty of Science, Damietta University, Damietta, Egypt

⁵ Zoology Department, Faculty of Science, Damietta University.

⁶ Zoology Department/Faculty of Science/Damietta University/Egypt

10.21608/ejabf.2025.409452.6318

Abstract

The recent establishment of Sardinella gibbosa, a non-indigenous clupeid, in the eastern Mediterranean Sea—specifically along the Damietta coastline of Egypt—raises important questions concerning its population dynamics and potential ecological implications. This study presents a comprehensive evaluation of the species' biological parameters based on 595 specimens collected between April 2023 and February 2024. Length-weight relationships revealed negative allometric growth (b< 3), accompanied by statistically significant sexual dimorphism in both length–weight relationships and condition indices. Growth modeling, employing the von Bertalanffy growth function, yielded higher asymptotic lengths in females (21.1cm) compared to males (20.2cm), with growth performance indices (Φ′) indicative of moderate somatic growth rates (Φ′ ≈ 2.24 and 2.26 for female and male, respectively). The reproductive assessment revealed a female-biased sex ratio and a length at first maturity (Lm) that closely approximated the estimated length at first capture (Lc), suggesting potential exposure to growth overfishing. Mortality and exploitation rates suggested that the stock is approaching its optimal harvest level. These findings provide essential baseline data to support the development of evidence-based management and conservation strategies for this recently established species in Mediterranean fisheries.

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