Female mantled howler monkey (Alouatta palliata) forages for leaves at Santuario Silvestre Wildlife Sanctuary in Costa Rica. Although this young female must use her prehensile tail as a hind leg because of a shattered kneecap, she has become the first female in a wild howler male's social group.

Active in primate research and conservation, Jennifer Weghorst served as a faculty resource for the Organization for Tropical Studies graduate course in tropical biology in Costa Rica, and she is the primate behavior adviser for the Santuario Silvestre Wildlife Sanctuary. She teaches in Kansas University’s Department of Ecology and Evolutionary Biology; she recently was appointed program coordinator for Latin America, Iberia, and the Caribbean for KU’s Office of Study Abroad.

The Organization for Tropical Studies (OTS) is a nonprofit, multi-country consortium of universities (including Washington University) and research institutes. OTS offers high-quality undergraduate and graduate courses in tropical biology and ecology, primarily in Latin America. Its flagship course is Tropical Biology: An Ecological Approach, which takes beginning graduate students to several ecosystems in Costa Rica and focuses on hypothesis-based science. At each site, students typically engage in a group research project led by a guest scientist familiar with the specific site and/or ecosystem.

For the past three years, I have been a guest scientist for this graduate course when the students have visited Sirena Biological Station in Costa Rica’s Corcovado National Park. I conducted my doctoral research on spider monkey behavioral ecology at this Pacific lowland, wet forest site. As part of my doctoral project, I conducted a line-transect survey of spider monkeys at Sirena and found that local population density was the second highest of any other studied site, likely due in part to the prominence of fig-dominated secondary forest and to a lack of logging and hunting activities. Several years after I completed my fieldwork, but before I served as a guest scientist for OTS, there were reports of a weather-induced die-off of spider monkeys and other animals in the vicinity of Sirena. The OTS group projects I have led for the past three years were line-transect surveys of spider monkeys in which we tested hypotheses related to demographics of a population recovering from mass mortality.

Costa Rican national parks, such as Corcovado, have park guards who monitor for poaching, pet trade activities, and gold mining. Although primates in the area around Corcovado are not hunted frequently for human food now, they may be killed and fed to hunting dogs by poachers targeting other game. Regardless of how vigilant any of the country’s national park guards may be, these guards have vast areas to patrol, and there will always be some animals that are casualties of illegal human activities. There are no governmental wildlife rescue or rehabilitation centers in Costa Rica, but the government works with permitted, privately operated centers, such as Santuario Silvestre (“Wild Sanctuary”) near Corcovado National Park and adjacent to Piedras Blancas National Park, run by Carol and Earl Crews (http://www.osawildlife.org/index.html).

Carol and  Earl Crews first contacted me four years ago, shortly after they had become caretakers of two rescued juvenile female spider monkeys: one that had been a caged pet for one year, and one — just days old — that had come to the sanctuary after her mother had been shot and killed in Corcovado. When I visited the sanctuary a second time for five days in mid-March 2008, I found that the two young orphans have become healthy, well-socialized, normal, young (4 and 6 years old) spider monkeys that are now “sisters” to a 2-year-old female. There is real hope for the future release of these three young female spider monkeys; monitoring their releases could be part of a doctoral research project (any takers? The Crewses welcome researchers!). Releases of any animals at the sanctuary must adhere to strict health standards. A veterinarian cares for all the sanctuary’s charges and is vigilant for zoonoses [infectious diseases that can be spread from animals to humans].

Currently all four species in Costa Rica are represented at the sanctuary: mantled howlers (Alouatta palliata), spider monkeys (Ateles geoffroyi), white-faced capuchins (Cebus capucinus), and squirrel monkeys (Saimiri oerstedii). Some have already been released successfully or are free-ranging. All the primates at the sanctuary have similar stories of being in or destined for the illegal pet trade, but they all are thriving behaviorally and physically at the sanctuary.