Caracterização da população de Hippocampus reidi no Estuário do Rio Pacoti, Ceará.

Abstract

Seahorses (genus Hippocampus) are bony fishes, which demonstrates lengthy parental care, low mobility and site fidelity. Both, biological and ecological characteristics classifies the seahorses as vulnerable species to extinction risk. Besides that, these small fishes are exploited due to their great commercial value to ornamental fish trade and traditional medicine. In addition, they suffer from the damage of their natural habitat. In Brazil, Hippocampus reidi is the most abundant species. In 2017, this species was classified as near threatened by IUCN. Regarding all this situation of vulnerability of this species and the results of past studies in Ceará, Brazil, this study aimed to characterize the current situation of H. reidi population in estuary of Pacoti River, Ceará. The samples were taken in six visits (May – August 2017 and March – April 2018). During the sample period, twenty-four transects (100 m²) were conducted, where were found twelve specimens of H. reidi, collected its data and, after that, the specimens were released back to the wild. For each specimens, it was collected data about holdfast structure used by them, sex, colour pattern, depth where the individuals were sampled and height. Also, the data of population density of this study were compared to the data of population density collected in 2008 during the same months and at the same colleting area. This temporal comparison showed that seahorse population density decreased.