ABSTRACT
RESUMEN La captura promedio anual de la pesquería de la jaiba azul (Callinectes sapidus) (JA) en Tamaulipas, México se estima en 2 733 T, de la cual, el 82 % se pesca en la Laguna Madre, sitio que se considera aprovechado al máximo de su capacidad. El objetivo de la presente investigación fue modelar la captura anual de la JA en la Laguna Madre, Tamaulipas, mediante el ajuste de funciones matemáticas de tipo lineal y no lineal (o curvilínea), a la serie de tiempo de 1998 a 2012, además de identificar las fases de desarrollo de la pesquería, de acuerdo a varios modelos generalizados. Se utilizó el enfoque de la teoría de la información y el procedimiento de la inferencia multimodelo (IMM). Se ajustaron 11 modelos de regresión lineal y no lineal. Para la selección de modelos se utilizaron los criterios de información Akaike corregido (CIAc) y bayesiano (CIB). Para el IMM se consideró el nivel ∆i <2de plausibilidad de CIAc y CIB. Los modelos elegidos para el IMM fueron compuesto, crecimiento, exponencial, logístico, potencial y el sigmoideo, considerándose como más adecuados los primeros cuatro modelos citados. Los modelos promedio del IMM presentaron valores de β 0 y β 1 de 0.939 y 0.377 respectivamente, según CIAc; y de 0.952 y 0.344 respectivamente, de acuerdo al CIB. Solo los modelos compuesto y logístico mostraron significancia estadística en sus dos parámetros de regresión (β 0 y β 1). El índice de sustentabilidad pesquera reveló seis periodos de la captura y una disminución en magnitud de los cambios de la captura. La serie de datos analizada incluye dos ciclos de vida de acuerdo a los modelos de Csirke y Caddy. Los resultados mostraron que al final del periodo estudiado la pesquería se encontraba en colapso y decadencia.
ABSTRACT The average annual catch of the blue crab (Callinectes sapidus) (BC) fishery in Tamaulipas, Mexico is estimated at 2 733 T, of which the 82 % is caught in the Laguna Madre, which is considered to be exploited to the maximum of its capacity. The objective of the present investigation was to model the annual catch of the BC in the Laguna Madre, Tamaulipas, by adjusting mathematical functions of the linear and nonlinear (or curvilinear) type, to the time series from 1998 to 2012. In addition, the phases of development of the fishery, according to several generalized models, were identified. We used the information theory approach and multimodel inference procedure (MMI). Eleven linear and nonlinear regression models were fitted. For the selection of models, the corrected Akaike corrected (AICc) and Ba-yesian (BIC) information criteria were used. For the MMI, the level ∆i < 2 of plausibility of AICc and BIC was considered. The models chosen for the MMI were compound, growth, exponential, logistic, potential and the sigmoid, with the first four models being considered the most suitable of all those cited. The average models of the MMI presented values of β 0 and β 1: 0.939 and 0.377 respectively, according to CIAc; and 0.952 and 0.344 respectively, according to the CIB. Only the composite and logistic models showed statistical significance in their two regression parameters (β 0 and β 1). The fishery sustainability index revealed six catch periods and a decrease in magnitude of catch changes. The data series analyzed includes two life cycles according to the Csirke and Caddy models. The results showed that at the end of the studied period the fishery was in collapse and decay.
ABSTRACT
The tambaqui, Colossoma macropomum, is one of the most commercially valuable Amazonian fish species, and in the floodplains of the region, they are caught in both rivers and lakes. Most growth studies on this species to date have adjusted only one growth model, the von Bertalanffy, without considering its possible uncertainties. In this study, four different models (von Bertalanffy, Logistic, Gompertz and the general model of Schnüte-Richards) were adjusted to a data set of fish caught within lakes from the middle Solimões River. These models were adjusted by non-linear equations, using the sample size of each age class as its weight. The adjustment evaluation of each model was based on the Akaike Information Criterion (AIC), the variation of AIC between the models (Δi) and the evidence weights (wi). Both the Logistic (Δi = 0.0) and Gompertz (Δi = 1.12) models were supported by the data, but neither of them was clearly superior (wi, respectively 52.44 and 29.95%). Thus, we propose the use of an averaged-model to estimate the asymptotic length (L∞). The averaged-model, based on Logistic and Gompertz models, resulted in an estimate of L∞=90.36, indicating that the tambaqui would take approximately 25 years to reach average size.
O tambaqui, Colossoma macropomum, é uma das espécies de peixes amazônicos de maior valor comercial, sendo capturado em rios e lagos da planície alagável da região. Até o presente, a maioria dos estudos sobre essa espécie tem ajustado um único modelo de crescimento, o de von Bertalanffy, sem considerer as possíveis incertezas associadas ao uso do modelo. Neste estudo, quatro modelos diferentes (von Bertalanffy, Logístico, Gompertz e o modelo geral de Schnüte-Richards) foram ajustados a um conjunto de dados de peixes capturados no interior de lagos situados no médio Solimões. Esses modelos foram ajustados por equações não lineares e o número de tambaquis em cada classe de tamanho foi usado como peso no ajuste. A avaliação do ajuste de cada modelo foi baseada no Critério de Informação de Akaike (AIC), na diferença do AIC entre os modelos (Δi) e nos pesos de evidência (wi). Tanto o modelo Logístico (Δi = 0,0) como o de Gompertz (Δi = 1,12) foram suportados pelos dados, mas nenhum deles foi claramente superior (wi, respectivamente, de 52,44 e 29,95%). Assim, é proposto o uso de um modelo médio para estimar o comprimento assintótico (L∞). O modelo médio, baseado nos modelos Logístico e de Gompertz, resultou em uma estimativa de L∞ = 90,36 e indicou que o tambaqui levaria aproximadamente 25 anos para atingir esse tamanho.