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Understanding the biology of fishing resources is a basic tool in order to define their adequate administration, and for that, trophic ecology studies gather important information about the spatio-temporal distribution of fish populations and their preys. Using passive fishing tackles such as longline and gillnets, 373 specimens of the gafftopsail sea catfish Bagre marinus were caught from which, 252 stomachs were analyzed. Forty-one food items were identified and classified in different groups of which, fish remains, the fish Anchoa sp, peneid crustaceans, the fish Cathorops mapale, fish eggs and vegetal material were the most frequent ones. The diet analysis indicates that it is an omnivore species. The feeding habits of this ariid, respond to an estuarine gradient in direction south-north, with significant differences between seasons and no significant overlapping between sites. To the north, the peneid crustacean preys are dominant in the diets, apparently due to high salinities of this zone that favor their abundance, while the south zone, characterized by large extensions of mangroves, is apparently an adequate area for a wider spectrum of marine and estuarine preys, particularly fish. [ABSTRACT FROM AUTHOR]

The Region of Murcia has approved an order that establishes a temporary fishing ban for longline and purse seine fishing in inland waters. This measure is taken in compliance with the regulations of the European Union that seek the sustainable exploitation of fishing resources in the Mediterranean. The order establishes temporary restrictions for certain fisheries that directly affect regulated resources. In addition, a fishing ban period is established for swordfish and white tuna fishing in the Mediterranean. [Extracted from the article]

The operational efficiency of the longline hauler on an artisanal tuna fishing vessel from Margarita Island, Venezuela, was determined using the average setting velocity, average hauling velocity, hauler input tension (To) and traction strength (P). A direct relationship was found between the average gravity (qmed) on the long-line section and the hauler input tension (To). Considering a strength (Pmed) at the input of the longline hauler (S1), the roller tension (S3) decreases due to the force of H = 23.7 N exerted by the pressure roller, resulting in a strength of S4 = 0. The longline average setting velocity was 208 m min-1 (~ 333 hooks/hour) and its hauling velocity was 121 m min-1 (~ 160 hooks/hour), whereas hauler input tension (To) was 1013 N. Therefore, the new traction strength (P) fluctuated between 1.317 and 1.418 N. Based on torque output from the rollers of the longline hauler, the average hauling velocity (vmed) and the transmission relations (k1, k2), a required average strength (Nmed) of 5.3 hp (~ 3.95 kW) for longline retrieval was estimated. Thus, the hauling efficiency (Tp) by longline section was estimated to be 135.4 s. [ABSTRACT FROM AUTHOR]