Effects of Different Intensities and Wavelengths of Light on the Growth of Juvenile Tridacna noae

Giant clams play a vital role in the preservation of coral reef ecosystems; however, the population of juvenile Tridacna sp. has experienced a decline primarily attributed to low survival rates, overfishing, marine pollution and the effects of climate change. Light intensity reportedly influences the growth and survival of giant clams. They possess the ability to thrive in oligotrophic tropical marine environments by utilising photosynthates from symbiotic zooxanthellae (Symbiodiniaeae). This study assessed the impact of different light intensities and wavelengths on growth rate (GR) and survival rate (SR) of juvenile T. noae. GRs of juvenile T. noae cultivated under 12,500 (518 +/- 69%) and 20,000 lx (541 +/- 40%) were significantly higher compared to those grown in 5,000 lx (271 +/- 17%) (P < 0.05). Additionally, juvenile T. noae cultivated under white (662 +/- 142%) or red light (554 +/- 135%) exhibited lower growth rate than blue light (BL, 727 +/- 146%). However, no significant change in SR was observed among experimental groups (P > 0.05). This study emphasised the significance of light intensity and wavelength in captive rearing of giant clams, contributing to the sustainable production of cultured organisms for research and conservation purposes.