Growth Characteristics of the Thick-Lipped Grey Mullet Chelon labrosus (Risso, 1827) from Bardawil Lagoon, Southeastern Mediterranean, Egypt

El- Aiatt, Attia; Shalloof, Kariman Ahmed Shawky; Ali, Shimaa; Ali Omar, Mohamed Attia

doi:10.21608/ejabf.2025.428972.6702

Growth Characteristics of the Thick-Lipped Grey Mullet Chelon labrosus (Risso, 1827) from Bardawil Lagoon, Southeastern Mediterranean, Egypt

Document Type : Original Article

Authors

¹ Fisheries Biology Lab. National Institute of Oceanography and Fisheries, Egypt.

² Fisheries biology Lab. National Institute of Oceanography and Fisheries(NIOF), Egypt

³ Lakes and Fish Resources Protection and Development Agency (LFRPDA)

⁴ Lakes and Fish Resources Protection and Development Agency (LFRPDA

10.21608/ejabf.2025.428972.6702

Abstract

The IUCN Red List classifies Chelon labrosus as Near Threatened. It is a species that has economic importance in the southeast Mediterranean. Thus, to support sustainable management of its stock in Bardawil Lagoon, this study provides baseline biological and fisheries data. A total of 472 specimens, ranging from 14.3– 43.1cm in total length and 40.0– 765.3g in body weight, were collected during the 2023 fishing season. The length–weight relationship followed the equation W=0.0105L^3.02, suggesting that the species exhibits isometric growth. Age determination from scales revealed seven age classes, with mean lengths at the end of each year estimated at 15.3, 19.6, 23.4, 27.1, 30.4, 32.9, and 34.5cm for ages one through seven, respectively. According to the von Bertalanffy growth model, the estimated growth parameters were L_∞ =47.4cm, K=0.152yr ⁻¹, and t₀=−1.508 yr, while the growth performance index (ϕ′) was calculated as 2.535. Mortality rates were estimated as Z = 0.848 yr⁻¹ (total), M = 0.419 yr⁻¹ (natural), and F = 0.429 yr⁻¹ (fishing), yielding an exploitation rate (E) of 0.51. The estimated length at first capture was 21.9cm, corresponding to an age of 2.56 years. The results suggest that the stock is experiencing moderate overexploitation. Therefore, a reduction in fishing mortality of approximately 29–30% is advised to secure the long-term sustainability of C. labrosus in Bardawil Lagoon. These findings provide the first comprehensive biological and fishery insights for this species in the region and highlight the urgent need for science-based management measures.

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