Spider monkeys (Genus: Ateles) are a widespread Neotropical primate with a highly plastic socioec... more Spider monkeys (Genus: Ateles) are a widespread Neotropical primate with a highly plastic socioecological strategy. However, the Central American species, Ateles geoffroyi, was recently re-listed as endangered due to the accelerated loss of forest across the subcontinent. There is inconsistent evidence that spider monkey populations could persist when actively protected, but their long-term viability in unprotected, human-dominated landscapes is not known. We analyzed noninvasive genetic samples from 185 individuals in 14 putative social groups on the Rivas Isthmus in southwestern Nicaragua. We found evidence of weak but significant genetic structure in the mitochondrial control region and in eight nuclear microsatellite loci plus negative spatial autocorrelation in Fst and kinship. The overall pattern suggests strong localized mating and at least historical female-biased dispersal, as is expected for this species. Heterozygosity was significantly lower than expected under random mating and lower than that found in other spider monkey populations, possibly reflecting a recent decline in genetic diversity and a threat from inbreeding. We conclude that despite a long history of human disturbance on this landscape, spider monkeys were until recently successful at maintaining gene flow. We consider the recent decline to be further indication of accelerated anthropogenic disturbance, but also of an opportunity to conserve native biodiversity. Spider monkeys are one of many wildlife species in Central America that is threatened by land cover change, and an apt example of how landscape-scale conservation planning could be used to ensure long-term persistence.
The lack of information on how primates respond to habitat fragmentation across a variety of ecos... more The lack of information on how primates respond to habitat fragmentation across a variety of ecosystems and regions hampers conservation efforts in the fragmented landscapes where populations are most threatened. We investigated the status of primates in the highly fragmented forests of southwestern Nicaragua, a region containing some of Central America's few remaining patches of tropical dry forest. We surveyed primates in two areas, the Chococente Wildlife Refuge comprising the country's largest remaining fragments of tropical dry forest, and an area of Rivas just north of the Costa Rican border, where tropical dry forest exists in much smaller, more isolated patches without formal protection. Of the three species found in Nicaragua, howler monkeys ( Alouatta palliata ) were least affected by fragmentation remaining relatively abundant in both areas. However, capuchins ( Cebus capucinus ) and spider monkeys ( Ateles geoffroyi ) were far less abundant and have suffered local extinctions both inside and outside of protected areas. Interestingly, our data suggest that all three species are currently least threatened in the humandominated landscape on the Rivas Isthmus, the more fragmented study region where 106 forests receive no offi cial protection. In spite of extensive fragmentation, southwestern Nicaragua's remaining tropical dry forests may maintain a functioning metapopulation of primates, including populations of the endangered spider monkey. However, reasons why the endangered spider monkey is more common in the more fragmented region are unclear. Our results demonstrate both the surprising ability of primates to survive in highly modifi ed landscapes, and the critical importance of coordinating conservation efforts with private landowners, local communities, and other stakeholders. Planning for primate conservation in such anthropogenic landscapes must consider historical factors and larger spatial context. In Nicaragua, the local NGO Paso Pacífi co has adopted the spider monkey as a fl agship species, and is working extensively with landowners and local communities to conserve this species and the forest fragments in which it lives.
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Papers by Suzanne Hagell