rior to the recent Lower North East Regional Forest Agreement, the Manning Region centred on Taree on the Mid North Coast of NSW was particularly poorly endowed with nature conservation reserves, existing national parks and nature reserves barely covering 2% of the land area.
With the enactment of the Forestry and National Park Estate Act 1998, a number of new national parks and nature reserves were established in the region, bringing the proportion in reserves to a more respectable10%.
These reserves have all been long-standing NPA proposals.
The four reserves in part protect a landscape that is visually stimulating and has regional scenic significance.
The Lansdowne Volcanics are associated with the Comboyne Shield Volcano, a past catastrophic event that would appear to be a consequence of the passage of the Australian continent over a "hot spot" within the earths mantle.
The residual volcanic structures are of considerable geological significance because they provide an exceptional insight into the evolution of the Great Escarpment in NSW.
This age has been confirmed by dating of Tertiary volcanic rocks from the trachyte plugs and flows on and adjacent to the Comboyne Plateau.
The upper escarpment is fringed by a fertile basalt plateau, while lower down plunging ridgelines and low rounded hills dissipate into a subdued landscape of alluvial terraces (Pain & Ollier, 1986).Among the new additions are four natural gems that dominate the spectacular escarpment fringing the Comboyne Plateau and the nearby Lansdowne Valley.The four are Coorabakh National Park, Killabakh Nature Reserve, Coxcomb NR and Goonook NR.As a result of numerous surveys and assessments, at least twelve mammals, four birds, one reptile and three amphibians listed in the schedules of the Threatened Species Conservation Act are known to occur within the four reserves.The Comboyne Plateau and the adjacent Bulga Plateau are now outlying residuals of the Great Escarpment which, as a result of scarp retreat, has migrated further to the west.
According to Pain and Ollier, "the Comboyne basalts and related volcanic plugs enable a chronology to be derived, and in the immediate area of the plateaus, scarp retreat has brought their escarpments to their present position within the past sixteen million years".