Tamanho Populacional e Uso de Habitat de Uma Assembleia de Raias de Água Doce (Potamotrygonidae) na REBIO do Parazinho (Macapá, Amapá)

Abstract

The assemblage research may provide valuable information on the different ways distinct species respond to varied ecological factors. Tagging and recapturing are useful techniques used in the estimation of population parameters of populations with members that can be individually tagged and that cannot be consistently found. . The aim of this study was to investigate the patterns of the freshwater stingray population and the community population of the taxocene at the Reserva Biologica (REBIO) in Parazinho. Samples were collected every 2 months from March 2012 to January 2013 using a bottom longline with 50 hooks each and were monitored during every receding tide; a cast net, jigging, and drift net were also used. The stingrays were internally tagged with a Passive Integrated Transponder (PIT) microchip, which was inserted near the base of the tail; these stingrays were then released at the same capture site. The Jolly-Seber method was used for the estimation of population parameters for the taxocene. A total of 115 stingrays were captured, 7 of which were recaptured. These 115 stingrays comprised 8 different species classified as follows: Paratrygon aiereba, Potamotrygon motoro, Potamotrygon orbignyi, Potamotrygon scobina, Potamotrygon constellata, Potamotrygon cf. dumerilii , Potamotrygon sp., and Potamotrygon sp 1. The estimated size of the taxocene was very high, which was probably due to the active movement of the stingrays. The number of recaptures was high, and individuals were mainly recaptured from the same initial capture site. The stingrays also showed preference for areas with muddy soils. Keywords: Potamotrygon ; marking; Jolly-Seber.