Biodiversity

Kings Park and Botanic Garden covers approximately 400 hectares, including 267 hectares of significant remnant bushland.

Geology

The escarpment rises steeply from the Swan River to a height of 65 m and, as a high point in the landscape, is visible from the city foreshore and surrounding suburbs. Views from the escarpment overlook Perth city, the Swan River and Darling Scarp in the distance. Geologically it is within the Spearwood Dune System with soils of the Karrakatta Soil association.

Over time, leaching of the calcareous sands has led to the formation of limestone at greater depths. This is demonstrated by the limestone cliffs exposed above Mounts Bay Road. As a result of past weathering, Kings Park slopes from high areas in the south-east to low lying areas in the south-west. The limestone cliffs have been exposed as the Swan River receded, and are a significant landform of the bushland.

The soils can be divided into two main types: medium size, calcareous sands; and shallow sands with exposed limestone. Apart from sand varying in pH, degree of leaching and grain size, there are areas of sandy loams. The underlying sand loam sheets, with perched water tables (for some months of the year) are important as they coincide with more vigorous vegetation cover.

Flora

Within the Kings Park bushland, three major plant communities are supported - limestone heathland; Banksia woodland with B. attenuata, B. grandis, B. menziesii and B. prionotes; and low moist areas with Banksia ilicifolia. Prior to European settlement, the Kings Park bushland would have been dominated by tall Tuart (Eucalyptus gomphocephala), Jarrah (Eucalyptus marginata) and Marri (Corymbia callophylla) with Banksia species and Allocasuarina fraseriana sub-dominating. Today the woodlands are often dominated by Banksia species, Allocasuarina fraseriana and Dryandra sessilis. There are 324 species of local native plants growing in the bushland, which represents about 15% of the native flora of the Perth Region.

Of particular importance is the limestone escarpment. Only three relatively large areas of cliff-side vegetation, Kings Park, Blackwall Reach and Mt Henry can now be found along the Swan River. The mixed closed heaths of the escarpment contain a diverse and unique assemblage of shrubs, herbs, sedges and grasses normally associated with limestone heaths of nearer coastal areas. The mixed closed heaths in Kings Park are one of the most inland occurrences of these estuarine cliff communities and are contiguous with adjacent bushland areas.

Fauna

The bushland provides a corridor benefit to local birds and invertebrates, allowing the continuation of species migration through the urban environment. There are over seventy bird species, twenty reptile species hundreds of different invertebrates in Kings Park bushland. The Brushtail Possum (Trichosurus vulpecula) and a number of bat species represent the native mammals of the Park. Kings Park supports a rare population and habitat of native snail, Bothriembryon indutus (Scarp Snail). Usually the species occurs along the Darling Range, which has a granite and lateritic environment. The disjunct population in Kings Park bushland exists on limestone cliffs. The trapdoor spider, Aganippe rhaphiduca, although not rare, has 'localised' population differences in Kings Park. Usually it occurs on the Darling Scarp and in Jarrah forest to Albany.

Fungi

There is also a large variety of fungi found in the Kings Park bushland - current estimates are over 100 different species.