Though often referred to as a mountain range, the Stirlings are actually the eroded stump of ancient mountains. In this oldest of lands there have been no mountain building epochs for billions of years. It’s rocks hold the earliest known traces of animal life on earth, with their age of at least 1.2 billion years being more than double earlier estimates.
Known to the Noongar people as Koy Kyeunu-ruff, for the thick fogs that often swirl around the range, the area has significant spiritual values. Noongar people still live around the Stirlings, in towns like Tambellup, Cranbrook and Mt Barker, from where their spiritual centre is readily visible.
When the last pieces of the Gondwanan super-continent separated, the peaks of the Stirling Ranges were islands in a warm tropical sea. Each peak still has distinct ecological characteristics, and an impressive number of species are only known from one or two of the hills, including a number of invertebrates more closely related to groups living in wetter areas of Australia, or other Gondwanan continents, than to the drier areas surrounding the ranges. Of the over 1500 plant species in the park, 82 are endemic. Orchids proliferate, with over 123 species recorded, and there are nine species of Darwinia, some confined to specific peaks.
Despite its fame and popularity with visitors, the Stirlings are in ecological decline. Dieback fungus is rife throughout the Park, its spread probably accelerated by tourist road construction during the 1970’s. High visitation rates increase the risk of walkers spreading the fungus along the ridge tops, from where it rapidly washes downslope. Fire regimes have been drastically altered in the last twenty or so years. The peaks have always attracted lightning strikes, but the use of widespread and ferociously hot backburns, that race up the steep slopes, have damaged many of the endemic populations that cling to the most gullies. A number of endemic invertebrates appear to have been lost as the result of one particularly aggressive fire control attempt in recent years.
Far too rugged to be farmed, the long island of bush that makes up the Stirlings has a vital role in linking the forest with the inland. Indeed, in the protected valleys and lower slopes heathland and mallee grow amongst with the jarrah, marri and wandoo forests of the wetter southwest. The Stirlings is the inland limit for almost 150 plant species, and from the western peaks you can see across to the forests, while from the eastern peaks you look north to the wheatbelt and east across a mosaic of farmland and bush to the ‘Barrens’, the iconic peaks of Fitzgerald River National Park.