Brownsea Island Treasury to pay her death duties. Concerned the island could be sold to commercial developers, a campaign was started by local conservationist, Helen Brotherton, with the aim of purchasing the island to protect its natural habitats. The National Trust subsequently agreed to take over responsibility for the island if enough funds were raised and in 1962 its purchased Brownsea for £100,000. Work was carried out to prepare the island for visitors; tracks were cleared through areas overgrown with rhododendrons and firebreaks were created to prevent repetition of the 1934 fire. The Dorset Wildlife Trust leased a nature reserve on the
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