The influence of ants and ant manipulation on the cocoa farm fauna.
Abstract
Certain species of dominant ants were selectively eliminated from different subplots in order to elucidate the influence of ants and other factors on the fauna of a cacao farm in Ghana [cf. preceding abstract, etc.]. The results were analysed by principal components analysis ordination. Changes in the weather played the most important part in determining the composition of the fauna, but during the dull part of the year this influence was reduced and other factors became more important. These included the cacao-canopy density, the proximity of the cacao to secondary forest and the dominant ants.Certain species of ants were associated with these environmental factors and hence their individual influences on the fauna were sometimes difficult to separate. A characteristic community was associated with each of the three common dominant ants, the composition of which depended on their predatory and tending habits as well as their type of feeding specialisation. Artificial replacement of one dominant species by another led to partial changes in the composition of the community to one more characteristic of the newly colonised species. Replacement of less beneficial species of ants by Oecophylla longinoda (Latr.) or Macromischoides aculeatus (Mayr) could protect cocoa from any detrimental pests.