Revista de biología marina y oceanografía
versión On-line ISSN 0718-1957
CARVAJAL, Raúl I; SAAVEDRA, Miguel y ALAVA, Juan José. Population ecology, distribution and habitat assessment of Crocodylus acutus (Cuvier 1807) in the “Reserva de producción de fauna manglares El Salado” of the Guayaquil Gulf Estuary, Ecuador. Rev. biol. mar. oceanogr. [online]. 2005, vol.40, n.2, pp. 133-140. ISSN 0718-1957. doi: 10.4067/S0718-19572005000200007.
An assessment on the population ecology, distribution and habitat of the American crocodile (Crocodylus acutus) was conducted within the recent protected area “Reserva de producción de fauna manglares El Salado”, Gulf of Guayaquil, Ecuador. The study was developed along 15 km of mangrove channels and tidal creeks, using nocturnal spotlight boat surveys during the dry season (September to December, 2004). About four crocodiles, with a relative abundance of 0.45 ind./km, ranging 0.27-0.63 ind./km, were detected. Crocodiles were aggregated in the final extreme of a tidal creek (Estero Plano Seco), where the water salinity ranged 10.0-28.0 psu and releasing of effluents (>32.0°C) from electric power plants and run-off from urbanized centers have been evidenced. Most of the crocodile sightings occurred during low tide. The population was represented only by adults (50%) and juveniles (50%); subadults and hatchlings were not observed during the study period. The population density found in this study is one of the lowest densities for American crocodile in the American regions. The euryhaline ability and tolerance to inhabit elevated surface water temperature (thermoconformer) confirm the physiological adaptation of this reptile species. More ecologic and population studies are needed to elucidate some gaps and the environmental factors influencing on the species conservation, as well as the establishment of management strategies to ensure its survival.
Palabras clave : population; density; salinity; temperature; American crocodile.