A survey of the population of the African weaver ant, Oecophylla longinoda (hymenoptera:formicidae) in Contrasting habitats in Ile-Ife, South-Western Nigeria.

Abstract

The occurrence and abundance of the African weaver ants, Oecophylla longinoda were monitored in five sites in Obafemi Awolowo University, Ile-Ife, southwestern Nigeria in 1992 and 2005. The five sites were: Biochemistry Car Park (BCH), Biological Sciences Car Park (BSP), Parks and Gardens (PG), Forest Reserve (FR), and Teaching and Research Farm (TRF).The trees in these sites which supported the population of Oecophylla were noted and nests were subsequently collected from these trees during each sampling period. Results showed that the abundance of these weaver ants was higher in 1992 than in 2005. In 1992, nests of O. longinoda were found in all sites while in 2005, they were not found in BCH and TRF. The mean number of ants per nest in FR was significantly higher (P < 0.05) in 1992 than in 2005 while the number of ants collected from PG and BSP were comparable in the two years. Stability in population of Oecophylla in BSP and PG over 13 years suggests that weaver ant communities in these sites might be resilient to human and anthropogenic disturbances while the absence of these ants in BCH and TRF in 2005 could be traced to site disturbance and pesticide application respectively. Three tree species (Terminalia catapa, Blighia sapida, and Myrianthus aboreus) are reported for the first time as potential hosts of O. longinoda and their potential in re-infesting tree crops with O. longinoda in a biocontrol programme is stressed.

Keywords: Weaver Ants, Human Disturbance, Abundance, Nigeria