Encounter rate and behavior of Alouatta guariba clamitans in the Ilha Grande State Park, Rio de Janeiro state, Brazil

Research estimates the encounter rate, density, and population size of Alouatta guariba clamitans, a threatened species endemic to Brazil's Atlantic Forest, within Ilha Grande State Park. Findings indicate low encounter rates (0.04 ± 0.01 individuals per kilometer) and small group sizes, reinforcing urgent conservation needs due to yellow fever outbreaks that severely impacted Rio de Janeiro populations between 2017 and 2018. Data were collected over two periods (2003–2005 and 2009–2010), using distance sampling methods to assess behavior and ecological aspects, providing critical baseline data for future conservation strategies.

Ferreguetti, A. C., de Oliveira, A. B. M., Pereira, B. C., Santori, R. T., Geise, L., & Bergallo, H. G. (2020). Encounter rate and behavior of Alouatta guariba clamitans in the Ilha Grande State Park, Rio de Janeiro state, Brazil. Zoologia, 37, 1–10. https://doi.org/10.3897/zoologia.37.e36846