Mortality, growth and somatic secondary production of the bivalve, Pinna rugosa (sowerby), in suspended and bottom culture in Bahia de La Paz, Mexico

Abstract

The objectives of this study were the determination of mortality, growth, condition factor and meat yield, biochemical variables, and somatic secondary production of Pinna rugosa (Sowerby, 1835) in suspended and bottom conditions in Bahia de La Paz, Mexico. The use of each of these parameters was analysed as a decision element for managing the resource. The experimental design was based on the recruitment of wild spat on collectors and introducing bivalves of the same size into different areas. In each area, bivalve samples were used both in suspended trays, and lying on the bottom, approximating their natural occurrence, but surrounded by a plastic mesh fence. The stocking densities in both cultivation systems were 50, 100 and 150 m−2. The organisms were checked monthly for almost 2 years, recording various measurements. In one of the treatments that most closely represented the average, the growth values were 19.5 mm month−1 and 14.5 g month−1 in the first year, a length‐growth Von Bertalanffy K of 0.118 and an instantaneus growth rate in weight G of 4.77. During the first year, there was annual mortality of 22% on the bottom and 11% at the surface, with somatic secondary production, in dry weight, of 17.8 g per organism. The results of the estimation of each variable were submitted to a multifactorial anova. NO significant differences in K as a function of sites, cultivation systems or density could be found. The effect of site on instantaneous growth rate G was significant. The largest values were from the inner bay (site 1) where the highest mortality rate also occurred. Among condition factor, meat yield and biochemical components, only lipids showed a difference for systems and site factors. We concluded that secondary production gave statistical elements for the selection and culture decision‐making in all factors tested. The results showed good aquaculture prospects for P. rugosa.

Evaluating the bio-economic performance of a Callo de hacha (Atrina maura, Atrina tuberculosa & Pinna rugosa) fishery restoration plan in La Paz, Mexico

“…It is possible that biological and environmental conditions also contributed to this pattern. For example, as these scallops tend to aggregate, it wasn’t until sufficient density was accumulated that recruitment was able to increase [32]. As this mechanism unfolds over time and in space, it is only when enough individuals are concentrated in reduced patches that biomass is able to take off.…”

Cultivation of Pen Shells: An Example with Atrina maura in Northwestern Mexico

“…Rapid growth of small (young) A. maura coincided with the rise in seawater temperature during spring and summer and slow growth coincided with lower temperatures during autumn and winter. A. maura juveniles and P. rugosa have faster growth at higher temperatures (Arizpe 1995; Leyva‐Valencia 2001); however, P. bicolor has slower shell growth at relatively high temperatures when this species enters its major reproductive phase during spring/summer (Beer and Southgate 2006). In P. carnea , great variability in growth, coinciding with spawning, shows a negative effect of gonadal production on somatic growth (Narváez et al 2000).…”

“…In Australia, wild P. bicolor were collected and cultivated in lantern nets and then transferred to pocket (panel) nets that are commonly used in cultivating pearl oysters (Beer and Southgate 2006). P. rugosa is cultivated in a combination of suspended and bottom conditions; wild spat was cultivated in plastic trays (used for oyster cultivation) that were suspended from long lines and later transplanted to the bottom and surrounded by a plastic mesh fence (Arizpe 1995).…”

“…Bottom cultivation experiments for pen shells have shown contrasting results. Arizpe (1995) obtained 78% survival in a semi‐closed system (using plastic fences); Wu and Shin (1998) reported 90% mortality, largely from predation by fish and crabs on the open sea bottom. In our study, protective devices were essential to avoid predation by crabs ( Callinectes bellicosus ) and fish ( Paralabrax spp., Balistes spp., Sphoerides spp., and others).…”

“…( Pinna ) pectinata and A. maura have been produced under hatcheries conditions (Guo et al 1987; Robles‐Mungaray et al 1996). Cultivation trials have been carried out for P. bicolor (Wu and Shin 1998; Beer and Southgate 2006), P. carnea (Narváez et al 2000; Velasco and Borrero 2004), P. rugosa (Arizpe and Félix 1986; Arizpe 1995), A. pectinata (Maeno et al 2009), and A. maura (Miranda‐Baeza 1995; Cardoza‐Velasco and Maeda‐Martínez 1997; Cardoza‐Velasco 1998). These have provided valuable information.…”