Stock Status and Management of Greenback mullet, <i>Planiliza subviridis</i> in the East Hammar marsh, Iraq

Assessing the various parameters of population dynamics is crucial for managing fish stocks. In this context, the present study analysed the growth, mortality, recruitment, yield-per-recruit, and virtual population analysis (VPA) parameters of Planiliza subviridis inhabiting the East Hammar marsh, in Iraq, using FiSAT II software. 3,429 specimens of P. subviridis measuring between 12.3 and 30.0 cm in total length (TL) and weighing between 21.1 and 303.5 g were sampled from November 2022 to October 2023. The length-weight relationship, expressed as W= 0.0142*TL2.928 exhibited negative allometric growth. The growth parameters, including asymptotic length (L∞) and the growth constant (K), were calculated as 33.0 cm and 0.33, respectively. The length at first maturity was higher than the size at first capture. Mortality estimates indicated total mortality (Z) at 1.91, natural mortality (M) at 0.79, and fishing mortality (F) at 1.12, resulting in an exploitation rate (E) of 0.58. Recruitment of P. subviridis continued throughout the year, with one prominent peak in June. The relative yield per recruit analysis indicated that the current exploitation rate (Ecur= 0.58) is below the biological target reference points for the species (E0.1= 0.609) and (Emax= 0.748), suggesting that the studied stock is under-exploited. VPA results showed that mid-length (19 cm) was the highest fishing mortality (1.563). For effective management, it is essential to adjust net mesh sizes and adopt sustainable fishing practices to fulfil the criteria for good management (Lc50 < Lm50), ensuring the long-term sustainability of P. subviridis in this feeding region.