Dinâmica e sustentabilidade da pescaria industrial polivalente que opera no Mar Caribe e Oceano Atlântico da Venezuela

Abstract

The world marine fisheries since 1996, when it reached its maximum value of 130 million tons, has been oscillating, falling to 105 million tons in 2016, declining at a rate of 1.2 million tons per year. Venezuela, one of the most important fishing areas in the Caribbean - Atlantic, has shown a trend similar to world catches, reaching in 2004 its biggest catches of 618 thousand tons and from that moment having a 53% slope reaching in 2016 a total of 286 thousand tons. In 2009, as a government strategy to mitigate the impact of the elimination of the trawler industrial fleet that operated on the Venezuelan coasts, industrial fishing fleet Polivalente Costa Afuera (multigear) from Venezuela emerged. In this sense, due to the need for information on the performance of this fleet, the present study aimed to evaluate the dynamics and sustainability of the multigear industrial fishery that operates in the Caribbean Sea and the North Brazil Shelf through the characterization of the fleet and its performance, identification of the main species caught and the evaluation of the relative abundance of Sciades proops catfish as a target species for the fishery and its biological sustainability. Data included in the 2015-2018 period were used from the National Logbook Program (forms filled in by boat captains) and the National Program on Board Observers (forms filled in by trained biologists on board the boats) from the Socialist Fisheries and Aquaculture Institute of Venezuela and provided by the Ministry of Popular Power for Fisheries and Aquaculture. The Kernel Intensity Estimator determined that the main fishing area was the North Brazil Shelf (with 95% of total fishing sets). There was a change in the dynamics of the fleet, with an increase in the use of bottom longline, along with a decline in the use of traps, probably due to the overfishing of the resources exploited by the traps. An analysis of covariance showed a positive effect of decreasing the effort of the traps on the catches, and conversely a negative effect on the increase of the effort of the bottom longline on the catches. The CPUE of the main species captured by the industrial fleet Polivalente Costa Afuera, Sciades proops catfish (captured with bottom longline), was standardized using a generalized linear model with Tweedie distribution, considering as categorical variables year, quarters, boat category (based on in length) and fishing quadrant. The model showed that the standardized CPUE of Sciades proops had a significant increase during the year 2016 and soon fell in the years 2017 and 2018. Finally, the Adaptive Fisheries Assessment and Management tool (AFAM) was used to assess the performance of the fishery of Sciades proops captured by the industrial fleet Polivalente Costa Afuera during the period 2015-2018. Four sustainability indicators were estimated with the following results: 1. Species composition, indicating the existence of changes in species composition during the study period; 2. Froese indicator, showing overfishing of mega-spawners; 3. Standardized CPUE trend and 4. Catch trend, both decreasing at the end of the study period. The interpretation of the results together suggests a possible status of overexploitation of the resources, being necessary to consider applying preventive management of the fishery establishing a maximum catch limit along with a maximum catch length for the Sciades proops catfish.