Porongurup National Park is a national park in the Great Southern region of Western Australia. It covers , and is southeast of Perth and north of Albany.
The park contains the Porongurup Range, which is the relic core of an ancient mountain range formed in the Precambrian over 1200 million years ago. The Porongurup Range forms part of the Southwest Biodiversity Hotspot, which is one of 34 regions in the world noted for a rich diversity of flora and fauna species. The range contains many peaks and hiking trails, with the highest point being Devils Slide at ,followed by Nancy's Peak at 644 metres. Castle Rock (558 metres) is capped with The Granite Skywalk, a steel viewing platform which provides panoramic views of the surrounding karri forest.
History
The Porongurup Range is culturally significant to the Mineng and Koreng/Goreng sub-groups of the Noongar people. Minang man Larry Blight states:This is our most sacred site...Porongurup or "Borrongup" means totem in Noongar — a totem could be an animal or a plant that we inherit from our mother’s and father’s side when we are born.The Porongurup Range was first sighted by Europeans passing near Albany in 1802 but farming in the surrounding districts did not start until around 1859 when vegetables were first grown on the southern slopes of the range. The giant karri and jarrah trees of the range were first harvested for timber in the 1880s and timber leases did not begin to be withdrawn until 1925. The National Park was not gazetted officially until 1971, with an area of . This has now been increased to .
Geomorphology
The Porongurup Range is from east to west and consists of porphyritic granite peaks levelled into domes. The range is the remnant of a sizeable reservoir of molten granite that bubbled up when the Antarctic continent struck Australia in the Precambrian period, around 1200 million (1.2 billion) years ago.
The sea levels of the late Cretaceous were around 100 metres higher than today and during this time the Porongurup Range was an island surrounded by the sea.
Ecology
Flora
The Porongurup National Park contains over 700 native plant species and at least 300 macrofungi species. At least nine flora species are unique and found only in the park. Examples of plant groups present include: heaths (Epacridaceae), especially beard-heaths (Leucopogon); peas (Fabaceae), notably flame-peas (Chorizema), bitter-peas (Daviesia and Bossiaea) and poison-peas (Gastrolobium); native myrtles (Myrtaceae); pimeleas (Thymelaeaceae), notably rice flowers (Pimelea); sundews and pitcher plants (Nepenthales); bloodroots, conostyles, kangaroo paws and their allies (Haemodorales); and banksias and grevilleas (Proteales). It is also important for richness in lilies, orchids and allies (Liliales), notably native lilies (Anthericaceae), irises and allies (Iridaceae), and orchids (Orchidaceae).
High granite peaks create their own micro-climates due to their altitude and their capacity to attract topographic rainfall. This maintains cooler and moister climate conditions than the surrounding low-lying plains. A remnant island of karri forest prevails here, hundreds of kilometres east of the cool southwest cape where they are more commonly found. They thrive in the granitic soils (known as "karri loam") and cool, moist air.
On lateritic soils downslope, the predominant type of vegetation is a mixed forest of jarrah and marri, whilst on the highly exposed and frequently waterlogged summits, an open mossy herbland prevails.
Fauna
The mammal species in the National Park include the western grey kangaroo (Macropus fuliginosus), brushtail possum (Trichosurus vulpecular), pygmy possum (Cercartetus concinnus), mardo (or yellow-footed antechinus – Antechinus flavipes leucogaster), mooti (or bush rat – Rattus fuscipes fuscipes), quenda (or southern brown bandicoot – Isoodon obesulus fusciventer) and honey possum (Tarsipes rostratus).
Seventy-one bird species including the red-eared firetail (Emblema oculata) and Baudin's black cockatoo (Calyptorhynchus baudinii) are also found in the park.
At least 17 reptile species are known to inhabit the park including King's skink (Egernia kingii), the southern heath monitor (Varanus rosenbergi) and the marbled gecko (Phyllodactylus marmoratus). Several tree frog and southern frog species are also evident.