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We present an assessment of the modification of the vegetation condition found on Phillip Island relative to a fully natural pre-European (1750) reference state and the current land and sea birds recorded on the Island. The island became denuded between the late 1700s and mid-1850s. Introductions of pigs, goats and rabbits were made to feed to penal colony of the nearby Norfolk Island. Almost complete loss of vegetation types, extent and condition is attributed to a deliberate land management regime: used to feed the pigs and goats. Pigs and goats became extinct with the loss of vegetation on the Island. Rabbits persisted on the Island until 1988, when they were eradicated. Changes in the extent of vegetation cover has been remarkable from a very low level up to 1900-1980 (estimated <1%); it now covers large areas of the island including valleys and gulleys and cliffs (estimated 50%). Our analyses show that the condition of the largely passively recovered vegetation extent is not of a high condition relative to an assumed reference state (1750) for Pine – Hardwood Subtropical Rainforest. A reconstructed pre-European settlement (original) list of sea birds shows that sea birds diversity on the island have changed little in three recent bird surveys (1978-2015). A reconstructed pre-European settlement (original) list of land birds shows that land birds have obviously changed, with many of the current species not represented in the pre-European list. The current list of land birds, which make up most of the current list of species recorded on Phillip Island have invaded from the nearby Norfolk Island. We conclude that current bird species diversity and distribution on the island is a not a function of the condition of the indigenous native vegetation, assessed relative to a pre-European reference state, but rather it appears to be a response to the lack of mammalian grazing mammals and the present of open to dense shrubby vegetation.