Motu Matakohe, also known as Matakohe or Limestone Island, is a 37 ha (100 acre) island in the upper reaches of Whangarei Harbour, just off Onerahi, a seaside suburb of the city of Whangarei, Northland, New Zealand. Used for farming and industry for many years, the island is an example of ecological island restoration by a volunteer community group.