Variabilidad Temporal De Los Parámetros Poblacionales De La Langosta Espinosa Del Caribe [Panulirus argus] (Latreille, 1804) En Aguas De Cuba

Abstract

ABSTRACT Temporal variability in the population parameters of the Caribbean spiny lobster Panulirus argus (Latreille, 1804) in Cuban waters Modifications in life-history traits are often concomitant with prolonged periods of exploitation or changes in the environment, producing changes in population abundance. . Both of them act as selective forces and could affect population parameters behaviour like growth rate, reproduction output, natural mortality rate and size at first maturity. Because of the economic importance of Caribbean spiny lobster (Panulirus argus) for Cuba and other countries of western central Atlantic, it is necessary to make a careful study in its life cycle processes and changes happened in temporal scale. Data used were obtained from biological monitory program in Gulf of Batabanó, main fishing ground in Cuban waters, from 1963-2002. Estimates of annual growth parameters of von Bertalanffy´s growth function ranged from 170 and 199.1 mm carapace length for asymptotic length and 0.20 to 0.27 year-1 for the growth rate. Both parameters showed a decadal behaviour with significant cycles of 16 years for the asymptotic length and 16 and 20 years for the growth rate. A non linear multiple regression model indicated a relationship of both parameters with mean annual biomass and sea surface temperature, demonstrating a denso dependency conduct in the asymptotic length and growth coefficient better related with sea surface temperature. Estimates of annual size at first maturity indicates an increment in the temporal scale, with a minimum value of 82.69 mm (1983) and a maximum of 102,8 mm (1991) of carapace length. Significant negative relationships were obtained between size at first maturity and fishing effort, population abundance and recruitment, but no significant was observed with sea surface temperature, prevailing denso dependency factors on the behaviour of this parameter. Average reproductive activity process indicates the maximum expression between March and May, but an interannual variability was observed, this pattern could be delayed or move forward; annual index of ovigerous females showed a positive standardize anomaly between 1990-1997. Annual natural mortality rates obtained in the last 40 years had an average value for the period of 0.36 year-1 with variations between 0.33 and 0.38 year-1, with same standardize anomalies of growth coefficient. Changes observed in Cuban lobster population parameters in the temporal scale, could be reflecting a similar situation in its distribution range, taking into account the wide larval dispersal in the region. Present analysis reveals the plasticity of the species in different conditions of fishing, population size and recruitment, using a periodic strategy in its life history traits when faces denso dependency processes or climatic change, adjusting growth, natural mortality and size at maturity, to attain a size sufficient for production of a large clutch and to improve adult survival during periods of suboptimal conditions. Up to the present, lobster population parameters in Cuban waters has been used in population dynamics models with an stationary vision, their consideration in these models will improve catch forecast and will improve management decision to obtain the sustainable use of the stock.