Movimentação de duas espécies de Loricariidae através de bueiro em riacho neotropical: desempenho na passagem e comportamento diário

Abstract

The neotropical streams have a rich and important ichthyofauna, nevertheless, in many of these streams there are culverts in his course from the construction of highways. These culverts have the potential to enable the free passage of fish and even restrict the movements, especially upstream. The aim of this study was to evaluate the movement of two Loricariidae species, Ancistrus sp. and Hypostomus acistroides, with the RFID system in a Neotropical stream with a culvert in his course. The passage performance of these species and the daily behavior of the movements on culverts were compared. The results indicated possible difficulty in accessing the culvert: Hypostomus ancistroides has apparently most successful upstream movements relative to Ancistrus sp., demonstrating that besides the low levels of transposition, the culvert can still be a selective barrier to movement. The two species showed greater nocturnal activity, nevertheless, their behaviors differ between periods: the highest activity to Ancistrus sp. occurred dawn (0:00 to 5:59) and to Hypostomus ancistroides the movements were more intense at night (18:00 to 23:59) indicating possible temporal segregation of behavior.