Radio Tracking Puerto Rican Parrots: Assessing triangulation accuracy in an insular rain forest

Abstract

We evaluated the accuracy of a portable radio teIemetry system in an insular tropical rain forest in preparation for a long-term radio telemetry study of the critically endangered Puerto Rican parrot (Amazona vittafa). No significant differences were found among error biases when comparing receiver systems, transmitter heights, distances, and topographical inclinations. Error of bearings to transmitters placed at distances of 100 m and 200 m from receivers at ground and canopy levels averaged –1.12°. Error polygons ranged from 0.5 ha to 2.0 ha (at 100 m and 200 m distances, respectively). Error of bearings taken at long-range distances (0.9-2.8 km) and at elevated sites (mountain peaks and towers) providing “lineof-sight” access to test transmitters averaged 2.51”. Error polygons ranged from 12.2 ha to 118.4 ha (0.9 and 2.8 km distances, respectively). Radio wave emissions from communication towers on prominent peaks occasionally reduced signal reception from ground-based receivers and completely masked signal reception in some valleys during aerial tracking operations.

Citation

Lindsey, Gerald D.; Arendt, Wayne J. 1991. Radio Tracking Puerto Rican Parrots: Assessing triangulation accuracy in an insular rain forest. Caribbean Journal of Science 27:46–53.