Green Island (Dorset) Green Island (Dorset) Green Island is an island in Poole Harbour in the English county of Dorset. It lies in the central south part of the harbour, south of Brownsea Island and Furzey Island. The island is an Area of Outstanding Natural Beauty (AONB), Site of Special Scientific Interest (SSSI) and Special Protection Area (SPA). The island covers approximately at low tide while the central raised part of the island is approximately . The island is covered in extensive woodland in the centre, made up of Scots pine with several small zones of heathland. The island also has a large
Brownsea Island island has a heronry, in which both grey heron and little egret nest. There is a large population of non-native sika deer on the island. In the past the numbers have been higher than the island can sustain and have overgrazed. To try to limit damage to trees and other vegetation by deer, areas of the island have been fenced off to provide areas of undamaged woodland to allow other species such as red squirrels to thrive. The lagoon is noted for the large population of common tern and sandwich tern in summer, and a very large flock of avocets