Mount Frankland South

Mount Frankland South National Park is a 14,540-hectare protected area in the karri forest region of southwestern Western Australia, situated south of the Frankland River and adjacent to the Walpole-Nornalup area. The park protects outstanding karri and jarrah-marri forest communities in the high-rainfall southern Warren bioregion. It complements Mount Frankland North National Park in forming a comprehensive conservation system for the lower southwest forest landscape. The park is managed by DBCA.

The park supports the full karri forest fauna community. The critically endangered western ringtail possum depends on mature karri and marri trees. Forest red-tailed black-cockatoos are resident, nesting in large hollow-bearing karri and marri trees. Carnaby's black-cockatoos visit seasonally. Short-beaked echidnas, brush wallabies, quendas, and western grey kangaroos inhabit the forest. Tiger snakes and dugites are present in damp valley environments. Freshwater streams support marron in cooler sections.

Karri (E. diversicolor) dominates the park on moist, deep soils, with some trees exceeding 70 metres. Jarrah and marri transition communities occur on drier ridges. The understorey is diverse: karri oak (Allocasuarina decussata), karri hazel, native wisteria, and numerous terrestrial orchids. Riparian zones support swamp paperbarks. The park lies within the globally recognised Southwest Australian Floristic Region.

Archaean granite-gneiss overlain by deep laterite profiles typical of the Darling-Warren Plateau. The karri forest grows on deep clay-loam soils derived from moist, deeply weathered granite in valley and lower slope positions. The Frankland River system drains through the area into the Nornalup Inlet.

High-rainfall warm temperate Mediterranean climate (900–1,200 mm annually). Winters are wet and cool with frequent mist and fog. Summers are warm and dry. The high humidity and fog-drip contribute significantly to the moisture budget sustaining karri growth.

The area lies within Bibbulmun Noongar country. The Frankland River-Nornalup area was used by Noongar people as a major resource corridor connecting coastal and inland environments. European timber operations commenced in the wider region from the 1890s.

Mount Frankland South National Park was proclaimed as part of the integrated southern forest conservation system, extending protected karri forest coverage south of the Frankland River into the Nornalup area. DBCA manages the park with prescribed burning in coordination with the wider southern forest reserve network.

Bushwalking through tall karri forest. Wildlife observation. Spring orchid and wildflower walks. Connections to the Walpole-Nornalup area provide access to the Tree Top Walk and Valley of the Giants.

Located south of Walpole, accessible via the South Coast Highway and local forest roads. No dedicated facilities within the park. Walpole provides accommodation and services.

Phytophthora cinnamomi dieback, climate-drying-induced karri decline, western ringtail possum vulnerability, and altered fire regimes are the primary conservation concerns.