46 MARCH 2026 • WORLD AQUACULTURE • WWW.WAS.ORG The blackspot snapper (Lutjanus ehrenbergii) is a commercially important reef fish in the Arabian Peninsula (Griffiths et al, 2024). It is generalist carnivore, feeding on benthic invertebrates associated with turfing algae (i.e. amphipods, isopods) and small fish, and widely found on coral reefs and rocky substrata of the IndoPacific region (Randall, 1995; D’Agostino et al, 2020). In the United Arab Emirates (UAE), the fish, locally known as Naisarah, forms an important component of the coastal demersal fisheries resources where it is mainly caught using inter-tidal fixed stake trap nets known as Al Hadrah (Grandcourt et al, 2006 Grandcourt et al, 2011). The blackspot snapper is among the four most valuable species represented in the total fish landing volume in the UAE (Mitchelle et al, 2024). The fish is characterized by its early maturation, occurring at approximately 12cm, and it has a single spawning season occurring between March and June in the Arabian Gulf (Grandcourt et al, 2011; Dunne et al, 2023). The present study reports the first successful captive breeding of the blackspot snapper, L. ehrenbergii, in UAE as well as their larviculture techniques. Broodstock Collection From May 2023 to April 2024 Naisarah brood stock (Figure 1) was sourced from the waters around Abu Al Abyad Island using both gill nets and intertidal fence nets, Al Hadrah (Figure 2). Most of the brood stock collected by Al Hadrah were found to be in better condition than those collected with gill nets. Healthy brood stock were selected based on phenotypic characteristics and optimal size for breeding. and then transported to the hatchery using 5 ppm AQUI-S® anaesthesia (Aqui-s New Zealand Ltd). Upon arrival, the fish were kept in the quarantine facility for a period of 2 weeks, during which time they were treated with 25 ppm formalin for 30 minutes for seven days, and were fed ad libitum with chopped squid. On 25th April 2024 fish from the quarantine were sorted according to their sex and maturity status. Females above 150 g in weight with swollen abdomens and oocytes measuring >350 µm in diameter and males with running milt were selected for spawning. Spawning Induction and Larval Rearing A total of 44 females and 27 males were transferred to indoor spawning tanks. Both females and males were treated with a single dose of Human Chorionic Gonadotropin hormone (HCG). Females were treated at 1000µg/kg and males with a dose of 500µg/ kg. Spawning took place 24 hours after injection and all eggs were collected. Spawning continued from April 28th to May 5th, 2024. The total number of eggs collected was 4.2 million eggs, out of which 2.4 million (41.38%) were fertilized, having an average diameter of 750 ± 20 µm. Fertilized eggs were incubated in hatching baskets and embryonic development was continuously monitored during the incubation period and photographed using a light microscope, Nikon Eclipse Ci, Japan (Figure 3). Eggs hatched out in about 22±2 hours in 35 ppt at 27±1˚C. Hatching rate was 17.10% and the total number of larvae hatched was 410,000 (Table 1). The newly hatched larvae averaging 1.6 mm total body length were collected, counted and randomly stocked in three 15-ton tanks at a density of 9 larvae per liter. Water temperature was maintained between 27 and 30°C, photoperiod was maintained at 14:10 (light: First Record of Induced Spawning, Larval Rearing and Juveniles’ Development of the Blackspot Snapper, Lutjanus Ehrenbergii (Family: Lutjanidae) in the Emirate of Abu Dhabi, United Arab Emirates Balamurgan Vadivel, John Antony, Omer M. Yousif, Krishnakumar Menon, Muhammad S. Irshan, Balamugunthan T. Arunasalam and Jeremiah Buendia FIGURE 1. Wild collected brood stock of blackspot snapper. FIGURE 2. The traditional fishing trap, Al Hadrah in UAE.
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