Distribution and New Sightings of Goeldi’s Monkey (Callimico goeldii) in Amazonian Perú

Abstract

There is a general consensus on the geographic distributions of many primate species; however, the continuity and validity of species range maps are often inaccurate on a local scale. In the case of rare and cryptic species, census methodology is often insufficiently rigorous or specialized, resulting in probable false negatives. Callimico goeldii is a rare primate, with most of its geographical range purported to lie in Peru. We evaluate the accuracy of its predicted geographic range within Peru with an assessment of mammal surveys over the last 40 yr and the inclusion of new sightings from three sites. We found that of all 340 study sites, only 10.9 % indicate that this species is present, and only 51 % of these sites receive any government protection. The Sierra del Divisor Reserve Zone and the Rodal Tahuamanu Conservation Concession have the highest estimated densities of Callimico goeldii. We suggest using focal follows of sympatric tamarins and vocalization playbacks rather than traditional line transects to improve the likelihood of locating this species. Although the current range maps based on the available data are likely an exaggeration of the species’ true range, the inherent imperfections of standard census methodology when applied to rare and cryptic species can lead to underrepresentative range maps as well. For these reasons, it is clear that the current distribution map for Callimico goeldii is imprecise, and until its distribution is reassessed, its conservation status cannot be confirmed.