Title : Feeding morphology and growth dynamics of three commercially important fish species (Oreochromis niloticus, Cyprinus carpio, Sander lucioperca) from the Al Massira Reservoir, Morocco
Abstract:
Freshwater fish populations in Moroccan reservoirs remain poorly studied compared to their ecological and economic importance for local fisheries. This study characterized the feeding morphology and growth parameters of three commercially important species ,Nile tilapia (Oreochromis niloticus), common carp (Cyprinus carpio), and pikeperch (Sander lucioperca) , sampled monthly over 12 months (June 2022–July 2023) from commercial catches in the Al Massira Reservoir (Oum Er Rbia basin, Morocco).
Cranial biomechanics were assessed using the suction index (SI) and the mechanical advantage of jaw closing (MA). Common carp showed the highest suction capacity (SI median = 0.37), consistent with its omnivorous benthic feeding mode, while pikeperch displayed the highest jaw-closing mechanical advantage (MA median = 0.52), reflecting its piscivorous strategy; Nile tilapia occupied an intermediate position for both indices. Growth parameters estimated using the ELEFAN method (TropFishR, R software) yielded asymptotic lengths (L∞) of 59.97, 83.54, and 89.22 cm and growth coefficients (K) of 0.08, 0.12, and 0.08 year?¹ for the three species respectively, with growth performance indices (φ′) of 2.76, 2.94, and 2.83.
These results provide essential baseline biological data for the sustainable management of these species and a functional framework for evaluating how anthropogenic stressors, including persistent organic pollutants, may affect feeding efficiency and growth.
Keywords: feeding morphology, suction index, mechanical advantage, growth parameters, Von Bertalanffy, Al Massira Reservoir
