An Assessment of the Population of Cotton-Top Tamarins (Saguinus oedipus) and Their Habitat in Colombia

Abstract

Numerous animals have declining populations due to habitat loss, illegal wildlife trade, and climate change. The cotton-top tamarin (Saguinus oedipus) is a Critically Endangered primate species, endemic to northwest Colombia, threatened by deforestation and illegal trade. In order to assess the current state of this species, we analyzed changes in the population of cotton-top tamarins and its habitat from 2005 to 2012. We used a tailor-made “lure strip transect” method to survey 43 accessible forest parcels that represent 30% of the species’ range. Estimated population size in the surveyed region was approximately 2,050 in 2005 and 1,900 in 2012, with a coefficient of variation of approximately 10%. The estimated population change between surveys was -7% (a decline of approximately 1.3% per year) suggesting a relatively stable population. If densities of inaccessible forest parcels are similar to those of surveyed samples, the estimated population of cotton-top tamarins in the wild in 2012 was 6,946 individuals. We also recorded little change in the amount of suitable habitat for cotton-top tamarins between sample periods: in 2005, 18% of surveyed forest was preferred habitat for cotton-top tamarins, while in 2012, 17% percent was preferred. We attribute the relatively stable population of this Critically Endangered species to increased conservation efforts of Proyecto Tití, conservation NGOs, and the Colombian government. Due to continued threats to cotton-top tamarins and their habitat such as agriculture and urban expansion, ongoing conservation efforts are needed to ensure the long-term survival of cotton-top tamarins in Colombia.

Comparative assessment of behaviorally derived personality structures in golden-handed tamarins (Saguinus midas), cotton-top tamarins (Saguinus oedipus), and common marmosets (Callithrix jacchus).

“…In cotton-top tamarins, however, indices related to social behaviors were either part of ExtraversionCT or part of ConfidenceCT. Studies on wild groups of cotton-top tamarins report that this species lives in small, stable and cohesive groups where unfamiliar conspecifics that attempt to join established groups might be chased away (Ferrari & Lopes Ferrari, 1989;French & Snowdon, 1981;Neyman, 1977;Savage et al, 2016). It is therefore possible that not only the complexity of the ecological niche, but also the complexity of the social niche might be reflected in personality structure and, in particular, the number of dimensions that are present (Koski, 2014;Lukaszewski, Gurven, von Rueden, & Schmitt, 2017).…”

Inferential reasoning in the visual and auditory modalities by cotton-top tamarins (Saguinus oedipus).

“…The tamarins are of interest, as they share some of the factors mentioned above that could influence performance on auditory IR. Cotton-top tamarins are cooperative breeders with limited, small familial social groups (Neyman, 1978) consisting of five to 12 individuals (Savage et al, 2016). Although their social structure may not be as dense as some of the macaques tested by Petit and colleagues (2015), their unique (among primates) social structure can provide an interesting test for the density theory.…”

Estimating population sizes to evaluate progress in conservation of endangered golden lion tamarins (Leontopithecus rosalia)

“…long calls, [12, 33, 34], we used playbacks of these vocalizations as lures. The detection function is directly related to how the animals respond to the playbacks and to the percent of the group that can be detected [31, 32]. In order to estimate the detection function for GLTs, we carried out a preliminary study between August 2013 and November 2013 in forest fragments where radio-tagged tamarins were monitored weekly.…”

“…To secure more reliable estimates of GLT population sizes in areas where monitoring is limited, and thus improve conservation management, we adapted the “point transect with lures” procedure (detailed in [30]) used to census cotton-top tamarins ( Saguinus oedipus ) in Colombia [31, 32]. We refined this method by first conducting a field experiment to estimate the detection function (see Methods) and then applied the refined survey methods throughout the geographic distribution of GLTs.…”