Dinámica poblacional de <i>Donax denticulatus</i> (Bivalvia: Donacidae) en playa Carenero, costa sur oriental de Cuba

Abstract

Population dynamic of Donax denticulatus (Bivalvia: Donacidae) at Carenero Beach, Southeastern Cuba. Bivalve molluscs of Donax genus are a very important component of macro-invertebrate assemblages of sandy beaches, and some species are of commercial value in different countries. Although in Cuba Donax denticulatus is not a currently exploited species, the information concerning a stock assessment is a basic step for future use of this resource. With the aim to generate new data on this species structure, growth and secondary production, monthly samples of D. denticulatus were taken from a beach of the Southeastern coast of Cuba, from February to December 2008. Samples were taken from four stations located along the beach; three strata were marked (P1, P2 and P3) per station across the intertidal zone. Three replicated samples of sediments were taken from each stratum with a 0.025m 2 PVC core and were posteriorly sieved with a 1mm mesh. Histograms of shell length were constructed based on 1mm intervals and growth parameters were estimated using ELEFAN I routine of FISAT. Mean density ranged from 146.67-855.55ind./m 2 and no differences were found among months (ANOVA, p>0.05) but among strata (Scheffé, p<0.05). An association of recruits, young and adults abundances with the strata (X 2 , p<0.01) was found. Most of the recruits were found in the upper strata while young and adult individuals were abundant in the mid-lower strata. Size frequency histograms of this population showed recruitment between March-June. Growth parameters estimated by Von Bertalanffy were L ∞ =27.5mm and K=1.5/year; and the life spam was estimated in 1.5 years. Using the length-converted catch curve, the mortality rate (Z) was estimated in 4.97/year. Based in terms of Ash free dry mass (AFDM), mean biomass was estimated in 0.47g/ m 2 .year and the somatic production in 12.4g/m 2 .year. The renewal rate (P/B) estimated for this population was 26.38, the highest among other Donax populations. High densities, fast growth and high somatic production indicate that this population can be exploited for fishing purposes for which some management measures are proposed.

Crecimiento y producción de Donax striatus (Bivalvia: Donacidae) en playa Las Balsas, Gibara, Cuba

“…According to these data, D. striatus from Las Balsas beach had higher growth performance than populations of other Donax species inhabiting the same climate region. These values match with other species of the same genus located in temperate zones, but that have reach longer shell sizes; this could be explained by the estimation method used in this study (Ocaña, Apín, & Cala, 2013). Growth estimates based on length-frequency data may be biased for tropical species which present continuous recruitment along the year (Sparre & Venema, 1997).…”

“…Secondary production of D. striatus is higher than the overall median estimated by Petracco, Cardoso, and Turra (2013) to bivalves of sandy beaches. High renewal rate matches with values of some tropical species according to Herrmann et al (2009), nevertheless is lower than P/B rate reported for D. incarnatus, D. spiculum (Ansell et al, 1978) and for D. denticulatus (Vélez et al, 1985;Ocaña et al, 2013). The rapid growth and high turnover rate of D. striatus suggest a rapid recovery of the population.…”

“…The life span of 2.4 yrs calculated in this study is higher than precedent values found in other populations of the same species and even higher than D. denticulatus that has the same distribution range. Other populations of Donax in the Caribbean (Wade, 1968;Vélez, Venables, & Fitzpatrik, 1985;McLachlan et al, 1996;Rocha-Barreira et al, 2002;Marcano, Prieto, Lárez, & Salazar, 2003;Ocaña et al, 2013) do not last two years. Mortality rate obtained for D. striatus was higher than other tropical species such as D. incarnatus (Thippeswamy & Mohan Joseph, 1991) and D. dentifer (Riascos & Urban, 2002), was similar compared with D. obesulus (Velarde & Aguilar, 2008), and lower than a population of D. denticulatus from South-eastern Cuba (Ocaña et al, 2013).…”

Abundancia y crecimiento relativo de <i>Donax denticulatus</i> (Bivalvia: Donacidae) en playa Levisa, costa sur oriental de Cuba

“…Proporción de individuos por componentes de la población (reclutas, jóvenes y adultos) por estrato (S1, S2 y S3) de Donax denticulatus en playa Levisa natural mortality (Le Moal, 1993;Defeo & Alava, 1995), no fluctuations of the population from Levisa Beach could be related to the season of our survey. Monthly size-class histograms showed that recruitment only occurred in April-May, and it is possible that this population has a reproduction period during March-May, as reported in Carenero Beach (Ocaña et al 2013) near Levisa, contrary to some other populations that showed continuous recruitment throughout the year (Wade, 1968;Vélez et al 1985;Marcano et al 2003). Nonetheless, more extensive sampling is needed in successive years to reveal the D. denticulatus recruitment pattern in Southeastern Cuba.…”

“…Shell morphometrics and population dynamics of D. denticulatus were analyzed in the Carenero Beach (Ocaña & Fernández, 2011;Ocaña et al 2013). Considering that D. denticulatus is a potential unexploited resource for fisheries, it is important to conduct further research in order to evaluate stocks on some beaches.…”