Variação temporal da pescaria dirigida à pescada amarela Cynoscion acoupa, Lacépède, 1801 realizada no Estado do Pará no período de 1996 a 2007

Abstract

In the State of Pará, among the various species economically exploited, yellow hake stands out for being mainly caught by the artisanal fleet using a gillnet. Given the economic relevance of this resource in this study was made an analysis of the behavior of the fishery over time, from January1996 to December 2007, accounting for 12 years. Analyzing the behavior and composition of the yellow hake fleet, the average catch for each type of vessel in activity, as well as the efforts(net length in meters, sea days and numbers of fishermen). The abundance index was estimated by calculating the capture per unit effort CPUE for each type of vessel, then the Mann Kendall and Wavelet de Morlet trend tests were applied in the time series mentioned above. It was observed that the artisanal fleet off the coast of Pará is mainly composed of: medium-sized boat -MSB(6%); small boat -SB(62%) and motorized canoe-MC(25%). Over time there was a change in the fleet in which CAM-type vessels (CV =112.89)predominated at the beginning of the series was replaced by BPP (CV =53.53). The smaller vessels studied here, MON (200.36) and CAN (281.49) have decreased over time. The average catch made by the vessel BPP (CV = 96.59) and the MAC (CV = 44.76) do not exceed 600 kg of yellow hake landed. Mid size boats (CV =30.48) reach landing volumes of 5639 kg for the entire series. Throughout the study period there was atendency to decrease average catch and increase fishing effort. The effort made by multiply in these days and fishing gear length in meters correlated with the catch (t = 8.9352, df = 142, p =1.93e-15). The CPUE per vessel type declined from 2001. The estimate of the abundance index for each vessel type showed a decreasing trend. Wavelet`s analys is reveals periodicities every19 months, 22 months, and 32 months of the BMP index. BPP has periodicities from 4 to 16 months and 32 months. CAM's CPUE series has awell-marked period across the 23-month, 32-and 38-month series. In CPUE Pará's abundance index, which involves the effort and capture of all vessels, a period of 23 to 26 months is marked, 32 well marked throughout the series. The effort for the period studied increased, especially on seadays, indicating that the high catch values are linked to an increase in effort. The abundance indices, both general and for each type of vessel, reveals that may be decreasing the stock of yellow hake off the coast of the state of Pará.