Distribución; uso de hábitat y status poblacional del manatí (Trichechus manatus) en el tramo central del bajo Orinoco; Venezuela

Resumen

Resumen. Para evaluar el estado actual de las poblaciones de manatí en el tramo central del bajo Orinoco, en este estudio se realizaron registros de avistamientos directos e indirectos, así como entrevistas a lugareños. El estudio se llevó a cabo entre marzo 2007 y abril 2008. Se registraron 46 localidades de incidencia del manatí, ampliándose su área de distribución, observándose 14 animales en cinco localidades. Desde el 2005 al 2007, fueron capturados 12 manatíes (ocho cazados, cuatro en redes). Se ubicaron 24 comederos en 17 localidades, identificándose nueve especies de macrófitas acuáticas que pueden ser consumidas por el manatí, dos de ellas con rastro de consumo (Paspalum repens y Eichhornia crassipes). Dentro de las amenazas que afectan a la especie, la cacería sigue siendo importante aunque ha disminuido en el área. Las muertes accidentales por la pesca con redes, el tránsito de embarcaciones, mayormente en el cauce principal del Orinoco, y la degradación del hábitat resultan ser amenazas potenciales en el área.

Distribution, habitat use, and population status of the Manatee (Trichechus manatus) in the middle region of the Lower Orinoco River, Venezuela

Abstract. In order to assess the current status of populations of manatee in the middle region of the Lower Orinoco River, we have performed and analyzed reports of sightings, both direct and indirect ones, as well as interviews to local inhabitants. Research was carried out between March 2007 and April 2008. Manatees have been reported to be present in 46 localities, widening the known area of distribution. Fourteen specimens where seen in five different locations. Between 2005 and 2007 twelve manatees were captured (eight hunted, four in fishing nets). Twenty-four feeding sites have been reported in seventeen localities. Nine species of aquatic macrophyte were identified as possible sources of food to the manatee, two of them have been found with traces of consumption (Paspalum repens and Eichhornia crassipes). The main threat to the survival of this species is the hunting, even though this activity has diminished in the area. Other potential threats are the accidental death by fishing nets, collisions with boats, and habitat degradation.