The role of the tantalus monkey (Chlorocebus tantalus tantalus) in forest restoration via seed dispersal in a West African montane forest.

Abstract

Many of the world's tropical forests are under threat, with anthropogenic deforestation and degradation occurring at an alarming rate. Seed dispersal in an important process in forest restoration and regeneration, however seed rain is often low in degraded habitats, hindering reforestation efforts. Up to 90% of tropical fruit are dispersed by vertebrates, animal seed dispersers are incredibly important in maintaining forest health. Additionally, frugivores that disperse seeds into degraded areas may be of great importance in aiding natural reforestation. I therefore, investigated the potential role of the frugivorous monkey, Chlorocebus tantalus tantalus, in forest regeneration via seed dispersal. I assessed its patterns of habitat use, the quality and quantity of seed dispersal it provides, the effectiveness of current conservation management actions and the density of C. t. tantalus at Ngel Nyaki Forest Reserve. I found C. t. tantalus utilised forest, edge and grassland habitats, and dispersed seeds of 28 pioneer and forest edge species into these habitats. Moreover, the number of seeds dispersed per faeces was significantly higher in the grassland than the forest with means of 16.4 +/- 6.1 and 3.4 +/- 0.97 seeds >2 mm in these habitats respectively. Germination of C. t. tantalus dispersed seeds was highest in grazed grassland and lowest in grassland protected from grazing and fire, suggesting the current practice of fencing off grassland to protect from cattle grazing may not be sufficient on its own, due to seed-seedling conflict in habitat suitability. These findings combined with an estimated density of 28 +/- 10.8 C. t. tantalus individuals km⁻² suggests C. t. tantalus may benefit forest regeneration via its role as a seed disperser, provided appropriate management actions are implemented. This and other frugivorous species may play similar roles in other locations but such roles need to be investigated in order to implement management actions that ensure their seed dispersal benefits are maximised for forest restoration and regeneration.