Evaluating the culture suitability and growth performance of Goldspot mullet (Liza persia) in cage culture environment in the Khurushkul, Cox’s Bazar

Abstract

This experiment analyzed the ecological feasibility and culture performance of cage culture systems of Goldspot Mullet (L. persia) at Khurushkul, Cox's Bazar. The research was performed for 8 months, from March to October 2023, monitoring the four most important hydro-ecological parameters: pH, salinity, temperature, and dissolved oxygen to study their impact on the growth and survival of L. persia. For the experiment, 8,500 fry were stocked in 10 cages, that was, 850 fry per cage. The results showed that water quality remained within optimum limits with minimal adverse effects due to seasonal cultural fluctuations. The average monthly highest pH value of 8.3 was recorded in May, while the lowest value of 7.82 was recorded sometime thereafter. The highest recorded mean monthly temperature was 31.30°C in June and 29.1°C in August. Salinity ranged from a high of 21.86 ppt in March to a low of 19.97 ppt in August. In the present study, highest value of DO was recorded in September, at 6.11 mg/L, and very low in October, at 5.82 mg/L. The artificial cage culture of L. persia was ascertainable based on performance indicators like specific growth rate (SGR) averaging 2.508% per day and a feed conversion ratio (FCR) of 3.05 for the system. Average weights rapidly increased throughout the months toward September, with strong growth under favorable environmental conditions and proper feeding strategies. This research proposed considerations for possible improvements in feeding management efficiency and nutrient inputs into the system. The study pointed out Khurushkul as a prime candidate for the sustainable cage culture of L. persia in aquaculture development, food security, and the income generation of coastal communities. In the future, feed strategies could be complemented with modern aquaculture technologies.