Catchment sources of pollutants and impacts on the coral reefs of Kimbe Bay, PNG from terrestrial runoff

Project manager: Jon Brodie

Project collaborators: Emre Turak (AIMS), Allison Green (The Nature Conservancy), Simon Lord (New Britain Palm Oil Ltd)

Project funding: The Nature Conservancy and New Britain Palm Oil Ltd

This project studied damage to the coral reefs of Kimbe Bay , West New Britain Island , PNG believed to be possibly associated with catchment logging and oil palm development. The study concluded that there was damage to coral reefs in Stettin Bay from sedimentation particularly in the inshore south western section of the Bay, from Kimbe Town to Walindi with less damage inshore further north of Walindi and to the east of Kimbe Town. Reefs further offshore were damaged but not primarily from land-based sources but via bleaching and crown-of-thorns starfish damage. The greatest sources of above-natural sediment export to Stettin Bay were from logging and oil palm plantation development in the plant crop stage. Other sources exist such as gardens, mature oil palm plantations, urban and small crops but these were of lesser significance. Logging exports peaked in the 1980s and are now falling with the reduction of activity in the Stettin Bay catchment. Oil palm new development and replanting has continued and is now the most significant source. There is no clear evidence that nutrients (specifically nitrogen) runoff is causing problems but any such problems may be masked by the more acute damage caused by sedimentation.