This study examined Red Sea and Arabian Gulf coastline fish hatcheries of the leading aquaculture companies in Saudi Arabia for future sustainability strategies. Evaluations were performed on seven marine fish hatchery facilities in 2021. The factors estimated were production capacity, existing infrastructure, main cultured fish species, source of broodstock and seed stock, and range of water temperature and salinity. Six of seven coastline marine fish hatcheries lacked broodstock capacity. The water supply to all hatcheries is adequate from the Red Sea and Arabian Gulf coastline. In five hatcheries, discharge limitations will serve as constraints in their expansion and development. A live food production section was absent in five hatcheries. Most of the cultured species in hatcheries were Asian Seabass Lates calcarifer, Gilthead Bream Sparus aurata, Sabaki Tilapia Oreochromis spilurus, and Sobaity Seabream Sparidentex hasta. Only two hatcheries produced fry, with an average monthly fry production of 500,000–1,000,000 individuals. The source of seed stock in five hatcheries depended on imports or other hatcheries. Sustainability strategies should focus on increasing broodstock capacity, live food production, and new culture species.

Diversifying aquaculture in Saudi Arabia with the inclusion of finfish species already reared in the Mediterranean Sea requires a sufficient understanding of the preferences and limits of cultured fish under local conditions. This study was conducted using three finfish species, juveniles (135–155g), meager (Argyrosomus regius), European seabass (Dicentrarchus labrax), and greater amberjack (Seriola dumerili), to assess their growth performance under high temperatures for three-month-long thermal trials. Each species trial was performed in triplicates in a recirculating aquaculture system, while three temperature ranges, 24°C–25°C, 28°C–29°C, and 33°C–34°C, were tested, representing the average temperatures in the Mediterranean and Red Seas. Both meager and European seabass performed similarly between the first two temperatures, indicating that the optimum range lies within that thermal window. Growth performance indicates that it is lower for meager than it is for European seabass. The greater amberjack’s growth performance was similar for the first two temperatures. The temperature of tolerance was 33°C for all species. The species appeared to have similar thermal tolerance with notable differences in the preferable temperature for optimum performance. The findings of this study can be used to improve the growth performance and feed efficiency of Mediterranean species farming in temperature ranges ranging from 24°C–28°C.

An accurate vertical wind speed (WS) data estimation is required to determine the potential for wind farm installation. In general, the vertical extrapolation of WS at different heights must consider different parameters from different locations, such as wind shear coefficient, roughness length, and atmospheric conditions. The novelty presented in this article is the introduction of two steps optimization for the Recurrent Neural Networks (RNN) model to estimate WS at different heights using measurements from lower heights. The first optimization of the RNN is performed to minimize a differentiable cost function, namely, mean squared error (MSE), using the Broyden-Fletcher-Goldfarb-Shanno algorithm. Secondly, the RNN is optimized to reduce a non-differentiable cost function using simulated annealing (RNN-SA), namely mean absolute error (MAE). Estimation of WS vertically at 50 m height is done by training RNN-SA with the actual WS data a 10-40 m heights. The estimated WS at height of 50 m and the measured WS at 10-40 heights are further used to train RNN-SA to obtain WS at 60 m height. This procedure is repeated continuously until the WS is estimated at a height of 180 m. The RNN-SA performance is compared with the standard RNN, Multilayer Perceptron (MLP), Support Vector Machine (SVM), and state of the art methods like convolutional neural networks (CNN) and long short-term memory (LSTM) networks to extrapolate the WS vertically. The estimated values are also compared with real WS dataset acquired using LiDAR and tested using four error metrics namely, mean squared error (MSE), mean absolute percentage error (MAPE), mean bias error (MBE), and coefficient of determination (R 2 ). The numerical experimental results show that the MSE values between the estimated and actual WS at 180 m height for the RNN-SA, RNN, MLP, and SVM methods are found to be 2. 09, 2.12, 2.37, and 2.63, respectively.

The survival, growth performance, feed intake, and feed conversion ratio of cultured Sobaity Seabream Sparidentex hasta in local high temperatures of 24, 28, and 32°C were estimated in this study. Experiments were conducted in triplicates with 40 fish (99 g average body weight; 17 cm average total length) in each indoor 1‐metric‐ton fiber‐reinforced plastic tank. For 96 d, the fish were fed a commercial diet (6‐mm pellets, 46.36% crude protein, and 12.54% crude lipid). The results showed that survival and growth performance of juvenile Sobaity Seabream were affected by temperature. Total weight gain was significantly higher in the 32°C group (158.57 g), followed by the 28°C group (138.25 g), and the lowest weight gain was observed in the 24°C group (116.98 g). The feed conversion ratio (1.62) was significantly lower in the 32°C group than in the 28°C (1.8) and 24°C (1.85) groups. Feed intake was significantly higher in the 32°C and 28°C groups (6.20–6.43 g) than in the 24°C group (5.41 g). In the 32°C group, the survival rate was significantly lower. The condition factor showed no significant difference among the three temperatures. Overall, Sobaity Seabream farming is feasible at temperatures ranging from 24°C to 32°C.

Diversifying aquaculture in Saudi Arabia with the inclusion of finfish species already reared in the Mediterranean Sea requires a sufficient understanding of the preferences and limits of cultured fish under local conditions. Two trials involving European seabass, Dicentrarchus labrax (L.) juveniles of 126 g and pre-adult fish of 313 g were carried out in Saudi Arabia. The trials tested four locally available commercial feeds for 84 and 80 days to determine the growth performance of fish in local high salinity 42-45‰ conditions. The average final weight in juveniles was not significantly different among treatments. The weight gain was smaller in Diet 3, while the specific growth rate was highest in Diet 1 and smallest in Diet 3. The feed conversion ratio was similar in all diets. The average final weight in pre-adult fish showed no significant differences in final body weight, weight gain, or feed intake. The growth results appear to be in line with related research. Improvement of nutritional characteristics of the feed is expected to improve the performance of the fish.