Feeding morphology and growth dynamics of three commercially important fish species (Oreochromis niloticus, Cyprinus carpio, Sander lucioperca) from the Al Massira Reservoir, Morocco

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

Biography:

Dr. Loubna Ferraj holds a PhD in Biology, specializing in Ecotoxicology and Aquaculture, from Sultan Moulay Slimane University, Béni Mellal, Morocco (2025). Her research focuses on the growth, feeding ecology and contamination of freshwater fish by organochlorine pesticides, PCBs and heavy metals, and the associated human health risks, with the Al Massira Reservoir as her main study site. During her doctoral training at the National Laboratory for Pollution Studies and Monitoring (LNESP, Rabat), she gained expertise in pollutant extraction and GC-MS analysis. She has co-authored 18 scientific publications and presented more than 20 communications at international conferences. She currently teaches practical courses in biology, biochemistry and toxicology as a contract instructor at the Faculty of Sciences and Techniques of Béni Mellal.