Large macaws' occupancy and abundance in Beni savannahs, Bolivia

BERKUNSKY, IGOR; CEPEDA, ROSANA; MARINELLI, CLAUDIA; SIMOY, VERÓNICA; DANIELE, GONZALO; KACOLIRIS, FEDERICO PABLO; DIAZ LUQUE, JOSÉ ANTONIO; GANDOY, FACUNDO A.; ARAMBURÚ, ROSANA; GILARDI, JAMES D.

ORYX

CAMBRIDGE UNIV PRESS

Lugar: Cambridge; Año: 2016 vol. 50 p. 113 - 120

0030-6053

To determine trends in populations of parrots, monitoring programs that explicitly take into account the detectability are needed. We assessed an occupancy modelling that explicitly accounted for detectability as a tool for monitor the large macaws of Beni savannas: Blue-throated, Blue-and-yellow and Red-and-green Macaw. We also evaluated the joint presence of the three macaw species and we estimated their abundance in occupied areas. We discussed how our results could be applied in the ongoing monitoring of the Blue-throated Macaw and future monitoring programs for other macaw species. In 2011, we conducted an exhaustive survey in Beni savannahs, Bolivia. We estimated naïve occupancy and detection probabilities. We modelled occupancy and detection for the three macaw species by combining several site and visit covariates and we described their conditional occupancy. Macaws occupied two thirds of the surveyed area and at least two species occurred together in one third of this area. Probability of detection varied between 0.48 and 0.86. For each macaw species, occupancy was affected by the abundance of the other species, the richness of cavity nester species, and the distance to nearest village. We identified key areas for macaw?s conservation. The flexibility of occupancy methods provides an efficient tool for the monitoring macaw occupancy at the landscape level, allowing us to predict the range of macaw species with a relative low effort over a large number of sites. This technique can be transferred to other regions around the world in which the monitoring of threatened parrot populations requires innovative approaches.