A Primate in Peril
Callimico goeldii is the only recognized species of its genus and differs from other callitrichids in its anatomy, reproduction, behavior, and ecology. Where other tamarins have twins, it raises only single infants. While others roam high into the rainforest canopy, callimicos remain safe in the undergrowth. Most importantly, only two long-term study sites in Brazil and Bolivia, both disturbed by nearby human settlements, tell us all that we know about this distinctive creature, listed by the IUCN as vulnerable to extinction ((Cornejo, F. 2008. Callimico goeldii. In: IUCN 2013. IUCN Red List of Threatened Species. Version 2013.1. <www.iucnredlist.org>. Downloaded on 16 September 2013)).
How We Got Drawn Into the Callimico Mystery
In the winter of 2009, PrimatesPeru began a study on Saguinus fuscicollis and Saguinus imperator, the two known tamarin species (Primates, Callitrichidae) at the Los Amigos Field Station, in the hopes of learning about the callitrichid community as a whole. The field station had been in existence for about nine years, and the tamarin groups were a common sight but had never been studied before. Every new day was an adventure, involving the observation of new behaviors, landscape features, plants, and other wildlife.
One day, we observed three tamarins that looked completely different from the other Saguinus species. We identified them as Callimico goeldii or Goeldi’s monkey – rare, cryptic, and completely unknown at this site!
Over the next two years, we only saw this elusive animal in the presence of other tamarin species. In 2011, we were extremely fortunate in that Dr. Jennifer Rehg, one of the few people to have ever studied callimicos in the wild, decided to join our project and work from the Los Amigos Field Station for a year. Together, we learned its distinctive long-calls, verified its tendency to remain quiet and motionless when disturbed, watched it indulge in its proclivity for rare fungi, and gradually, we were able to habituate a few individuals. However, in some years we don’t see a single individual at all – making this a long-term effort.[vimeo 74689116 w=768&h=432]
An Assessment of Species Distribution
With our interest piqued, we recently reassessed the predicted species range for callimico by compiling a review of all mammal surveys to locate recent, verifiable sightings of this primate within Peru – wherein lies more than 75% of its range. We found a total of 34 locations, some verified decades ago, with all indications that the population at the Los Amigos Field Station, in southeastern Peru, is very special indeed ((Watsa, M., Erkenswick, G. A., Rehg, J. A., and Leite-Pitman, R. (2012) Distribution and New Sightings of Goeldi’s Monkey (Callimico goeldii) in Amazonian Perú.International Journal of Primatology Volume 33, Issue 6 , pp 1477-1502)).
Not only were the callimicos at this site reliably observed, they were habituated to observers and to baited platforms we have used in the past to safely conduct a tamarin-specific capture-and-release program. Through this program we have been able to individually identify morphologically identical tamarins, provide radio collars, and take vital health records. With these tools applied to the callimicos specifically, we would now be able to conduct full-day follows, and evaluate home ranges, feeding ecology, and reproductive behaviors.
The Importance of this Research
As Peru evaluates which of its regions require conservation, information on rare and cryptic species is critical to setting aside species-specific habitats that are less likely to receive traditional protection. Callimico goeldii, with its odd preference for secondary forest bamboo patches, is at risk of being completely ignored, due to a lack of country-specific information. Given that its densities are typically one-twentieth the densities of other tamarin species at the same sites, it is critical to identify if such densities are viable or restricted by some other factor. Food resource limitation, reproductive success, lengthy inter-birth intervals, and habitat types also affect population stability. This investigation will allow for the monitoring of a species that is yet to be studied within the majority of its range, at a site uniquely conducive to such an endeavor.
Positions Available for Summer 2018
We are not recruiting assistants specifically for this program at this time – however, the full research team will be keeping an eye out for this mysterious primate!