Rare sightings of the critically endangered yellow-tailed woolly monkey in Amazonian Peru
Scientists from a joint Field Museum- Nature and Culture International expedition encountered the critically endangered yellow-tailed woolly monkey (Oreonax flavicauda) well outside its previously known territorial and elevation ranges on a rapid inventory of the Cordillera Escalera in Loreto, Peru. Prior to these two new sightings on the inventory, O. flavicauda had not been observed by scientists in Loreto and it was thought to only occupy higher elevations between 1,500 to 2,700 masl (Shanee, 2013) despite lower elevation records of extirpated populations. In this study we investigate the significance of these two confirmed sightings at 1,200 and 1,600 masl and the implications they have on the protection of this species and conservation of their habitat. We used Maxent (Phillips, 2004) software with19 Worldclim (Hijmans, 2005) environmental variables and altitude data with distribution records confirmed by Shanee et al. (2010) to model the fundamental niche of O. flavicauda before and after adding our new distribution records. We also examine high-resolution deforestation land cover results from the University of Maryland (Hansen et al. 2013) as a surrogate measure of habitat quality, and we compare notes with our social inventory team who conducted interviews and natural resource mapping exercises with Shawi indigenous people.
When we include our new sightings in the Maxent analyses, they show a dramatic increase in the potential habitat and range of O. flavicauda that extends well into the Cordillera Escalera region and other parts of western Loreto. To address habitat loss, we used a 5 km buffer around all distribution points to look at the percent deforestation near observed populations. Deforestation was markedly lower around the new distribution points in Loreto, and it was significantly higher in areas where Shanee et al. documented recent extirpations. Interviews with Shawi people strongly suggest that populations of O. flavicauda have existed in Loreto for some time where they are actively hunted and on the decline. These populations coexist with people in Escalera where they may face higher predation risk as a tradeoff for higher quality habitat. Natural resource mapping exercises and interviews with Shawi people in the Escalera region, suggest that the Shawi hunt nearly the entire region with temporary hunting shelters scattered throughout. Our analytical results and social science information both suggest that permanent protection of the Cordillera Escalera region coupled with natural resource conservation planning with local populations would improve the conservation prospects of O. flavicauda.