Earlier events :: 2013 :: STUDENT Talks

Foraging ecology of Hipposideros aff. ruber in an agricultural landscape in Ghana, West Africa

Presented by
Evans Nkrumah
Department Of Wildlife & Range Management, Knust
Evans E. Nkrumah, Samuel Oppong, Marco Tchapka, Stefan M. Klose, Ebenezer K. Badu, Heather J. Baldwin, Priscilla Anti, Peter Vallo, Augustina Annan, Michael Owusu, Christian Drosten, Olivia Agbenyega, Yaw Adu Sarkodie, Elisabeth K.V . Kalko


Conversion of tropical forest to agriculture severely impacts wildlife populations. They are however increasingly becoming the only available habitats for some species such as Hipposideros aff. ruber, a common bat in Ghana. This work was therefore carried out to investigate the foraging ecology of this bat, and provide conservation recommendations on their habitat requirements to ensure their long term survival in the ever changing Ghanaian ecosystem.


Thirteen individuals of Hipposideros aff. ruber were radio tracked by two people. Bearing data was triangulated in LOAS vs and sent to LOCOH web application to create the foraging area (95% isopleth level). Foraging area was overlaid on a habitat map created, using ArcGis vs 10. The percent used to available habitat by each bat was calculated. A compositional analysis was then automated in Compos v6.3+ to rank habitats in order of importance to the foraging bats.


A generated ranking matrix indicated that, Hipposideros aff. ruber selected semi-natural habitats (SnH) (eg. Fallow lands) for foraging ahead of other habitats. Tree farms (TF) (eg. cocoa farms) were of less importance to foraging bats. Bats avoided the grassland areas during foraging, indicating they were of less importance. Also, bats used trees as night roost before returning to the cave, indicating their dependence on them.


Although adapted to foraging in all habitats, preference for SnH indicate the abundance of prey items and enough cover from view of predators. TF were used as flight paths from view of predators instead of foraging probably because of the use of agrochemicals compared to mixed farms. Their vulnerability to anthropogenic activities is proposed. Bats benefit from natural succession on fallow lands and tree re-vegetation on agricultural lands is also proposed.