Abstract

Light-traps and plankton nets are methods used to sample eggs, pelagic larval and juveniles fishes. However, light-traps are expensive and for this reason their use had been difficult in the researches in Venezuela. The purpose of this study was compare the capture of ichthyoplankton with standar nets and light-traps made in the laboratory of similar models to other international researches but with inexpensive materials. Samples were colected at nighttime on four localities of Mochima Bay, Venezuela. Similar numbers of larvae yieled with both methods (866 and 1,620 nets and light-trap, respectively). Nevertheless, 41 species (23 families) were capturated with light-trap, while 33 species (16 families) were identified in plankton nets samples, where just 12 families were shared among methods. A comparasion of larval size-distribution indicated that the size structures of the catches differed between collecting methods. Larvae yieled in plankton nets were smallest than larvae captured with light-traps (1.078 – 18.23 and 1.96 – 169.54 mm, respectively). Both light-traps and plankton nets were effective for collecting a range wide of taxonomic level on the study area; nevertheless, light-traps are a selective method because they target pelagic stages of fishes that are photopositive behaviour and advanced pelagic stages. The use light-traps in larval assemblages studies is advantegeous because to capture advanced stages let main precision on taxonomic identification. On the other hand, the accurate estimation of larval abundances and their frecuency it was able with the use of plankton nets, for this reason this method would be keeping in larvae assemblages reaserches.

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