Growth and survival in the fattening stage of Striostrea prismatica (Gray, 1825) native oyster in a suspended culture system, Tumbes, Peru (February 2019 – July 2020)

Abstract

We aimed to determine growth and survival rates, as well as yield in the fattening stages of the oyster S. prismatica in a suspended culture system considering the seasonal changes of some oceanographic parameters (temperature, salinity, and chlorophyll-a). In February 2019, we installed a longline at the geographical coordinates 3°38’36.7’’S and 80°36’53.6’’W, off Nueva Esperanza (Tumbes). A total of 1,600 oyster seeds produced at Imarpe’s Coastal Laboratory of Tumbes were used to start the research. The shell dimensions were length 9.3 ± 0.9 mm, height 9.1 ± 0.7 mm, and thickness 1.8 ± 0.3 mm, distributed in four 4-story lanterns, at a density of 100 specimens per story. The culture stage lasted 518 days, during which 17 biometric samplings were carried out; by the end of that stage, the averages in length, height, and thickness of the oysters were: 82.6 ± 10.6 mm; 86.2 ± 10.3 mm, and 37.9 ± 6.6 mm; the average monthly growth rates were 4.3 mm.month-1, 4.5 mm.month-1, and 2.1 mm.month-1There was a survival rate of 56.0%. The ANOVA applied to the monthly increments showed that no significant difference was found between length and height (ANOVA, F=1.14; p=0.29). The yield was 1: 0.1365 (1,000 kg of total weight yields 136.5 kg of body weight). Thermal and haline oceanographic conditions, as well as food availability (chlorophyll-a), were favorable for oyster growth during the trial.