 As of 2011, the environmental state of the harbour has been called as "nearing crisis" and "in significant decline", with shrinking fish and shellfish stocks, more sedimentation, declining water quality and competition for resource use and development being noted as the main issues, with "ninety-nine per cent of the rivers in the catchment [are] polluted".As part of the worldwide trend, there is a decline in biodiversity within the Kaipara.The timber industry removed most of the native forest.