Portal de Periódicos da CAPES

Individual home ranges of Tursiops truncatus and their overlap with ranges of Stenella frontalis and fishermen in Aragua, Venezuela, South Caribbean

2020; Cambridge University Press; Volume: 100; Issue: 5 Linguagem: Inglês

10.1017/s0025315420000557

1469-7769

Sergio Cobarrubia‐Russo, Guillermo R. Barreto-Esnal, Alimar Molero-Lizarraga, Miguel A. Mariani-Di Lena,

Animal Vocal Communication and Behavior

Abstract The coast of Aragua is a home of bottlenose dolphins (BND), Atlantic spotted dolphins (ASD) and fishermen (FIS) from four towns. A photo-identification study was carried out on BND to estimate their home ranges. From 2004 to 2008, 100 field surveys were carried out along 30 km of coastline (92.12 km 2 ). In each sighting of BND, information regarding date, time, latitude/longitude and photographs were registered (ASD and FIS were registered without photography). The data were analysed using a Geographic Information System to estimate Minimum Convex Polygon (MCP) and Fixed Kernel (FK) at 95%. The home ranges of BND were estimated for seven individuals. This included three females (29–31 sightings) with estimated areas ranging from 33.90–39.90 km 2 with MCP (36.79–43.31% of the study area) and from 80.47–101.31 km 2 with FK (109.97–104.26%). For the remaining four dolphins (14–20 sightings) the estimated areas ranged from 9.67–22.34 km 2 (MCP), the predominant depth of these home ranges varied from 51–100 m (χ 2 = 24.5, df = 2, P = 4.785 × 10 −6 ). For the pods of ASD the estimated area ranged 75.23 km 2 with MCP (81.66%) and 119.86 km 2 with FK (130.11%) with predominant depths of 101–200 m (χ 2 = 24.5, df = 2, P = 4.785 × 10 −6 ). The area used by FIS ranged 93.27 km 2 by MCP and 228.49 km 2 by FK. Finally, the overlap area of BND, ASD and FIS ranged 24.75 km 2 (26.86%). We point out this locality presents important oceanographic and ecological aspects which deserve to be the subject of application of management plans for the conservation of its habitat and species.