Prior to June 2000, Johnston's Genet was only known from a few (mostly damaged) museum skins and skulls. However, Dunham captured the first live specimen of Johnston's Genet (Genetta johnstoni) in TNP and fitted it with a radio-tracking device (Gaubert et al. in press). Philippe Gaubert, mammologist of the Natural History Museum of Paris, is presently examining the taxonomic status and genetic relationship of this species and other Viverrinae of Africa in a separate project. His team joined efforts with the Tai Mongoose Project in February 2001 and was able to capture an additional 3 live animals and sufficient DNA samples for his work. Frequent sightings of Johnston's Genet in the park suggest that this previously unknown species is quite common in the swamp forest and riverine habitat of TNP. The protection provided by the park may make it one of the last strongholds for this rare and largely unknown species.
The main focus of the Tai Mongoose Project is on the social mongooses in TNP. Through radio tracking of collared individuals and direct observations of habituated animals, much has been learned about the ecology and behavior of the Liberian Mongoose (Liberiictis kuhni) and the Western Cusimanse Mongoose (Crossarchus obscurus). The Liberian mongoose is a diurnal social mongoose living in small family units (4-6 individuals) with a diet specialized on earthworms. It is seriously threatened with extinction from habitat loss and intensive hunting for bush-meat throughout its restricted range. The distribution of this species is thought to be limited to the Cavally River basin and the protection of TNP is critical for its survival. The Western Cusimanse is an insectivorous species living in large social units up to 24 animals. Habituated mongooses have been seen to cooperate in hunting cobras and giant rats, to share pup rearing, and to form polyspecific associations with Diana and Mangabey monkeys, most likely as an anti-predator strategy against the African Crowned Eagle.
In addition to basic research on the natural history of these species, research examines the ecological effects of invertebrate predation and soil disturbance by these mongooses in the rainforest of TNP. A yearlong exclosure experiment is being conducted to examine the impact of invertebrate predation of litter fauna and the related trophic cascades affecting leaf herbivory, litter fragmentation, and nutrient cycling. In addition to predation effects, the physical removal of litter and surface roots by mongooses during foraging may also have ecological importance. Family groups of Liberian Mongooses commonly plough up large areas of topsoil while foraging for earthworms, considerably altering the surface of the ground; a pilot study estimated an average production of 16,700 foraging scrapes per day per km2 in swamp forest. The potential impacts of this disturbance on seedling recruitment and mortality are being investigated through exclosure experiments, germination tests, and direct observation. Forest mongooses are facing decline in Ivory Coast and surrounding areas due to intensive hunting pressures. Results of this study will suggest how the loss of such species from forest habitat may affect the terrestrial community, ecosystem processes, and seedling biodiversity in West African rainforests. Within a broader scope, results will increase our knowledge of terrestrial food web ecology and examine the importance of indirect interactions between vertebrates and plant communities, which until recently, has been largely ignored.
Gaubert, P., Veron, G., Colyn, M., Dunham, A., Shultz, S. & Tranier, M. in press. A reassessment of the distributional range of the rare Genetta johnstoni (Viverridae, Carnivora), with some newly discovered specimens. Mammal Review.
Englischer Text des Authors:
The Taï Mongoose Project is lead by Amy Dunham, of the State University of New York at Stony Brook. The project focuses on the ecology and behavior of small carnivores (Viverrids and Herpestids) of Taï National Park (TNP). Small forest Carnivora have received little attention from the scientific community in the past due to the inherent difficulties associated with studying elusive forest species. As a result most observations made of these species in the wild are discoveries new to the scientific world.