Developing a national spat collection program for pearl oysters in the Fiji Islands supporting pearl industry development and livelihoods

Cultured pearl farming in Fiji relies on wild spat collection to supply the oysters used for pearl production. This supply can be inconsistent and a research program was implemented to determine recruitment of pearl oysters to spat collectors at sites throughout Fiji as a basis for developing a national spat collection program to improve reliability of oyster supply to the industry. Twenty-nine sites across Fiji were used in this study. Spat collectors consisted of a 100m longline from which 310 individual spat collectors were suspended. Spat collectors were deployed for a period of 10–15 months when the number of pearl oyster (Pinctada margaritifera and Pteria penguin) spat attached to each collector was counted and shell size recorded. A total of 5478 P. margaritifera juveniles were collected from all sites with the highest number of recruits (693) and the highest number of recruits per collector (2.10 ± 0.17) occurring at Nacobau (Vanua Levu). The largest mean dorso-ventral measurement (DVM) of P. margaritifera at any site was 8.61 ± 0.30 cm while the smallest was 4.26 ± 0.13 cm. Some sites did not record any P. margaritifera recruitment during the study and these were generally sites with relatively turbid water. A total of 4224 Pt. penguin were collected from all sites, with the highest number of recruits (495) recorded from Namarai (Viti Levu). The mean DVM of Pt. penguin ranged from 7.53 cm to 13.62 cm across sites. Results indicate that Pt. penguin have greater tolerance of more turbid inshore sites than P. margaritifera based on greater levels of recruitment at these sites. Results identified sites supporting high levels of pearl oyster recruitment as a basis for an ongoing national spat collection program, and support better targeting of spat collection activities that maximise oyster supply to the Fijian pearl industry. The national spat collection program will generate significant livelihood benefits across Fiji and support continued expansion of the Fijian cultured pearl industry.;