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The paper shows the experience in handling the design of Caibarien- Santa Maria key causeway to fit it with the environmental characteristics of the watershed in which it is located. By means of a cause-effect modeling graphic, corroborated by an up-dated informatics software, it is demonstrated the fundamental character that keeping the ocean-island shelf interchange has, as well as the hydrodynamics, in the preservation of the marine environmental characteristics. It is also explained the general strategy that was followed, on the assumption that the causeway is, according to the environmental point of view, a hydraulic construction as a set of its main components: the road layout, the calculation of bridges by hydraulically quasi-homogenous sections, the manner the bridges are located, the off-road induced works and the so-called ecological bridges. [ABSTRACT FROM AUTHOR]

This paper presents the reproductive condition and feeding spectrum of four batoid species caught as bycatch by artisanal fishermen in two sectors of the Colombian Caribbean Sea between August 2005 and September 2006. Specimens were evaluated from a total of 570 hauls done off Salguero beach and 149 off Don Jaca, with sampling periods of 12 to 26 days per month. The total and relative abundance of the batoids caught were determined, as were the sexual proportion and representativity of each sexual maturity stage. Specimens sampled were: 176 Narcine bancroftii (127 females, 49 males); 167 Rhinobatos percellens (83 females, 84 males); 237 Urotrygon venezuelae (126 females, 111 males), and 119 Dasyatis guttata (58 females, 61 males). Although specimens from all stages of maturity were caught, the immature (I) and mature (III) stages were dominant. Based on the sexual proportion obtained, no marked spatial-temporal segregation was observed. The overall diet consisted of crustaceans, annelids, and teleosts, with unique food preferences that allow the sampled species to avoid interspecific competition. [ABSTRACT FROM AUTHOR]