Evaluación de la abundancia y el hábitat de Crocodylus intermedius y otros crocodrilianos en el rio Bita (Vichada, Colombia)

Abstract

En la presente investigación se abordaron tres preguntas de investigación relacionadas con la abundancia y hábitat de los cocodrilianos, además de la distribución y presencia de la presión humana a lo largo del río Bita. Las preguntas relacionadas con la abundancia y el hábitat de los cocodrilianos se abordaron a lo largo del río Bita y durante diferentes épocas de muestreo, por medio de un diseño de ocho transectos de longitud definida, para realizar recorridos y mediciones de las variables del hábitat. Los registros de presión humana se realizaron a lo largo de todo el río y durante las tres épocas de muestreo (Texto proporcionado por el autor).

We search with this research work, to evaluate aspects related to crocodilians in the Bita River, such as the presence, abundance, population structure, spatial and temporal variation, as well as an assessment of the conservation status of Crocodylus intermedius along the river Bita. We defined eight transects along the river and conducted nocturnal spotlight surveys in three different climatic times. Two species Caiman crocodilus and Paleosuchus palpebrosus were recorded. We did not register C. intermedius, which shows that the species became extinct locally or its density is very low for the study area. The maximum number of registered crocodilians was 626, of these 548 we identified them as Ca. crocodilus, 25 as P. palpebrosus and 53 as only eyes. The average relative abundance for Ca. crocodilus and P. palpebrosus was estimated at 3.1 and 0.5 ind / Km respectively. We found that the abundance of Ca. crocodilus is not distributed homogeneously in the sampling periods (H = 8.984, Gl=2; p = 0.0112), nor along the river (X2 = 11.571, p = 0.038). For P. palpebrosus we did not find significant differences between the sampling periods (H = 0.7841, Gl=2, p = 0.6708). The population structure of Ca. crocodilus varied between the sampling times of lower and onset of precipitations (X2 = 19,049, Gl = 3, p = 0,0003), in addition to being more abundant the size classes I and II during all the Sampling times. The structure of the population of P. palpebrosus is represented by adults over 80 cm.