Papers by Johannes Refisch
Tropical Conservation Science, 2008
As a result of forest modification, primates are increasingly having to rely on fragments; so too... more As a result of forest modification, primates are increasingly having to rely on fragments; so too are the human populations that have historically relied on continuous forest for critical resources. The role of primates in seed dispersal is increasingly understood to have significant unique effects on plant demography and forest regeneration. Our aim in this paper is to explore the potential for monkey seed dispersers to maintain the utility of forest fragments for humans through seed dispersal in the Taï region, western Côte-d'Ivoire. We established a list of fruit species whose seeds are dispersed by seven of eight monkey species occurring in the Taï National Park by using primary data and published accounts of their fruit diet, and determined the abundance of human-used and monkey-dispersed tree species in forest fragments in the broader Taï region. The monkeys of the Taï National Park consumed 75 tree species. Of this total set of 75 species, 52 (69%) were dispersed almost exclusively by monkeys and were found in neighboring forest fragments. Of the 52 fruiting forest tree species that are dispersed by Taï monkeys, 25 (48%) have some utility to local inhabitants suggesting that maintaining populations of primates is important not only for forest regeneration, but also for human populations that rely on forest resources. The conservation of primate species is a critically important goal in itself, but by working to ensure their protection in forest fragments, we certainly protect indirectly the seed dispersal of important human resources in these fragments as well.
A RAPID RESPONSE ASSESSMENT 4 5 This report, based on evidence submitted to the UN Security Counc... more A RAPID RESPONSE ASSESSMENT 4 5 This report, based on evidence submitted to the UN Security Council, field investigations, interviews and scientific data indicates that the gorillas in the Greater Congo Basin are at even greater risk than expected less than a decade ago.
A population census of chimpanzees (Pan troglodytes schweinfurthil) was conducted in the original... more A population census of chimpanzees (Pan troglodytes schweinfurthil) was conducted in the original part of Kahuzi-Biega National Park. Zaire. The census provides the first estimate of the density of chimpanzees in montane forests of Equatorial Africa. At least three unit groups of chimpanzees were identified in the census area during the 1990 bamboo season. The estimated density (0.13 chimpanzees/km 2 ) falls within the range of densities in savanna. the driest chimpanzee habitat. The estimated density was far lower than the density of gorillas that sympatrically inhabit this montane forest. even though the two apes have been found at almost equal density in tropical forests in other areas. Chimpanzees were typical forest-dwellers. but gorillas ranged over various types of vegetation. including the open vegetation and the swamp. The low diversity and availability of fruits in the montane forest are responsible for the low density of chimpanzees who are frugivorous in various habitats. At least five out of eight primate species raided crops around the borders of the park. Chimpanzees raided maize and plantain bananas. The hostility of the local people towards these primates has recently become heightened in this area. More international attention is needed to augment conservation activities and to protecl. these primates . from the hazards of human disturbances in this area.
Biotropica
We studied the impact of hunting on monkey species in the Taï National Park and adjacent forests ... more We studied the impact of hunting on monkey species in the Taï National Park and adjacent forests in Côte d'Ivoire. The average wild meat consumption per capita per year was assessed from market surveys and interviews. We determined that the amount of primate wild meat being extracted in the Taï National Park and surrounding forests was 249 t in 1999. Hunting pressure was the highest on the larger primate species such as red colobus, Procolobus badius, black and white colobus, Colobus polykomos, and the sooty mangabey, Cercocebus torquatus atys. Estimates of population densities were based on line transect surveys. The maximum annual production of each species was calculated using the Robinson and Redford model (1991) and assuming unhunted conditions. Comparing current harvest levels with the maximum sustainable yield suggests that harvest of red colobus monkeys (Procolobus badius) is sustainable, whereas current off-take of the black and white colobus (Colobus polykomos), the sooty mangabey (Cercocebus atys), diana monkeys (Cercopithecus diana), and Campbell's monkeys (Cercopithecus campbelli) exceeds sustainability by up to three times.
International Journal of Primatology, 2005
We studied the effect of market hunting on primate species in the Taï National Park and adjacent ... more We studied the effect of market hunting on primate species in the Taï National Park and adjacent forests in Côte d'Ivoire. We assessed the impact of hunting by comparing the calculated maximal reproduction rate with the current offtake rate. We assessed the average bushmeat consumption per capita/per year from weekly investigations on bushmeat available in 88 bushmeat restaurants and markets over a 12-mo period in 1999. We derived data on preferences for particular game species from interviews of 162 bushmeat consumers, 25 subsistence hunters and 3 groups of professional hunters. Hunting pressure was highest on the larger primate species such red colobus (Procolobus badius), black-and-white colobus (Colobus polykomos) and sooty mangabeys (Cercocebus atys). The amount of primate bushmeat extracted from the Taï National Park and surrounding forests was 249,229 kg in 1999. We estimated population densities using line transect surveys. By referring to current population densities we calculated the maximum production of each species using the Robinson Redford model (2001) and assuming unhunted conditions. A comparison of current harvest levels with maximum production suggests that harvest of Procolobus badius is sustainable, whereas current off-take of Colobus polykomos, Cercocebus atys, Cercopithecus diana (diana monkey) and C. campbelli (Campbell's monkeys) exceeds sustainability by ≤3 times.
Biotropica, 2005
We studied the impact of hunting on monkey species in the Taï National Park and adjacent forests ... more We studied the impact of hunting on monkey species in the Taï National Park and adjacent forests in Côte d'Ivoire. The average wild meat consumption per capita per year was assessed from market surveys and interviews. We determined that the amount of primate wild meat being extracted in the Taï National Park and surrounding forests was 249 t in 1999. Hunting pressure was the highest on the larger primate species such as red colobus, Procolobus badius, black and white colobus, Colobus polykomos, and the sooty mangabey, Cercocebus torquatus atys. Estimates of population densities were based on line transect surveys. The maximum annual production of each species was calculated using the Robinson and Redford model (1991) and assuming unhunted conditions. Comparing current harvest levels with the maximum sustainable yield suggests that harvest of red colobus monkeys (Procolobus badius) is sustainable, whereas current off-take of the black and white colobus (Colobus polykomos), the sooty mangabey (Cercocebus atys), diana monkeys (Cercopithecus diana), and Campbell's monkeys (Cercopithecus campbelli) exceeds sustainability by up to three times.
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Papers by Johannes Refisch