Optimum temperature for growth of an invasive green mussel Perna viridis population from Venezuela, determined in an open-flow system

Abstract

Optimum temperature for growth of an invader population of green mussel Perna viridis (31.1 ± 1.9 mm SL; 0.8 ± 0.2 g DTW) from Guayacan Venezuela, was determined by means of scope for growth (SFG) at 22−34 °C with an open-flow system. The objective was to find the suitability of its cultivation in the Gulf of Cariaco Venezuela. Morphometric relationships of shell length vs. wet and dry weights were obtained to determine the condition index of experimental mussels. SFG was highest at 26 °C (64 ± 16 J g−1 h−1), was positive at 22–30 °C (35 ± 3 and 20 ± 1 J g−1 h−1 respectively) and negative at 34 °C (-39 ± 11 J g−1 h−1). Mussels employed were at good condition indicated by a positive allometry of shell length–total wet weight (b-value = 3.7394) (R2 = 0.397) which was higher than in native populations. Condition index (2.01–13.49) indicated that the mussels studied were not active in reproduction. Based on SFG results and temperature published data from the Gulf of Cariaco, it is concluded that temperature-wise this site (20.1–29.1 °C) is appropriate for aquaculture of the population of P. virids studied. Further studies on the combined effect of temperature and seston concentrations over SFG are needed since a combination of high temperature and seston depletion frequently occurs in this site from September to January. The advantages of the new open-flow sytem for ecophysiological studies in aquatic organisms are discussed. Keywords: Scope for growth, Allometry, Perna viridis, Ecophysiology