Spatial ecology of the giant armadillo Priodontes maximus in Midwestern Brazil

• Published in: Journal of mammalogy 2020-02, Vol.101 (1), p.151-163
• Main Authors: Desbiez, A. L. J., Kluyber, D., Massocato, G. F., Oliveira-Santos, L. G. R., Attias, N.
• Format: Article
• Language: English
• Subjects: autocorrelated kernel density estimates; Cingulata; conservation; conservação; densidade mínima; Estimativas de densidade de Kernel para dados autocorrelacionados; Feature Articles; fidelidade territorial; home range; interação estática; minimum density; Pantanal; site fidelity; static interaction; telemetria; telemetry; Xenarthra; área de vida
• ISSN: 0022-2372; 1545-1542
• DOI: 10.1093/jmammal/gyz172

The giant armadillo (Priodontes maximus) is the largest living armadillo. This naturally rare and poorly known species is endemic to South America and classified as “Vulnerable” by the IUCN. Here we explored aspects of the spatial ecology of P. maximus in Midwestern Brazil to gain insights on its ecology and biology to support conservation efforts. In 8 years, we identified 50 individuals of P. maximus and monitored 23 of them using telemetry methods. To characterize site fidelity and home range, we fitted individual continuous-time movement models and estimated Autocorrelated Kernel Density Estimates. We built a Structural Equation Model to evaluate how home-range area and daily displacement are related to each other, to sampling effort, and to individual characteristics. We estimated home-range overlap between pairs of different sexes using a bias-corrected Bhattacharyya coefficient. Finally, we formulated a canonical density estimation formula to characterize minimum population density. We gathered a total of 12,168 locations of P. maximus. The best-fitted movement models indicated site fidelity for all individuals and a median adult home-range area of 2,518 ha. Median adult daily displacement was 1,651 m. Home-range area scales positively with daily displacement and daily displacement scales positively with body mass. Median home-range overlap between pairs was low (4%) and adult females presented exclusive home ranges among themselves. Median minimum density was 7.65 individuals per 100 km2 (CI = 5.68–10.19 ind/100 km2). Our results are congruent with characterizing P. maximus as a generally asocial species, most likely promiscuous/polygynous, that establishes large, long-term home ranges, which grants the population a naturally low density. Spatial patterns and biological characteristics obtained in this study can be used to guide future conservation strategies for P. maximus in the Pantanal wetlands and elsewhere.