The Eyre Yorke Block is an Interim Biogeographic Regionalisation for Australia

Interim Biogeographic Regionalisation for Australia

The Interim Biogeographic Regionalisation for Australia is a biogeographic regionalisation of Australia developed by the Australian Government's Department of the Environment, Water, Heritage and the Arts...

 (IBRA) region and a World Wildlife Fund ecoregion

Ecoregion

An ecoregion , sometimes called a bioregion, is an ecologically and geographically defined area that is smaller than an ecozone and larger than an ecosystem. Ecoregions cover relatively large areas of land or water, and contain characteristic, geographically distinct assemblages of natural...

 covering the Eyre

Eyre Peninsula

Eyre Peninsula is a triangular peninsula in South Australia. It is bounded on the east by Spencer Gulf, the west by the Great Australian Bight, and the north by the Gawler Ranges. It is named after explorer Edward John Eyre who explored some of it in 1839-1841. The coastline was first explored by...

 and Yorke Peninsula

Yorke Peninsula

The Yorke Peninsula is a peninsula located north-west and west of Adelaide in South Australia, Australia, between Spencer Gulf on the west and Gulf St Vincent on the east. It has geographic coordinates of...

s around the Spencer Gulf

Spencer Gulf

The Spencer Gulf is the westernmost of two large inlets on the southern coast of Australia, in the state of South Australia, facing the Great Australian Bight. The Gulf is 322 km long and 129 km wide at its mouth. The western shore of the Gulf is the Eyre Peninsula, while the eastern side is the...

 on the coast of South Australia

South Australia

South Australia is a state of Australia in the southern central part of the country. It covers some of the most arid parts of the continent; with a total land area of , it is the fourth largest of Australia's six states and two territories.South Australia shares borders with all of the mainland...

.

Location and description

These peninsulas consist of hilly country originally covered in eucalyptus

Eucalyptus

Eucalyptus is a diverse genus of flowering trees in the myrtle family, Myrtaceae. Members of the genus dominate the tree flora of Australia...

 woodland. However this is good soil for farming and the woodland has mostly been cleared for agriculture now. This coast has a temperate climate with a wet winter (300mm to 600mm of rainfall per year).

Flora

The original vegetation of these low hills was woodland of short trees with a shrubby undergrowth. The original woodland consisted mainly of a tea tree Melaleuca lanceolata

Melaleuca lanceolata

Melaleuca lanceolata is a small tree or shrub in the genus Melaleuca, native to Australia. It has a number of common names including Black Paperbark, Moonah, Rottnest Island Teatree and Western Black Tea tree....

and mallee box (Eucalyptus porosa), a mallee

Mallee (habit)

Mallee is the growth habit of certain eucalypt species that grow with multiple stems springing from an underground lignotuber, usually to a height of no more than ten metres...

 eucalyptus. The flora of the two peninsulas does differ with that of the Eyre Peninsula having similarities with areas further west as well as number of endemic species, while the Yorke Peninsula has plants typical of areas to the east.

Fauna

Mammals of the region include the Eastern Grey Kangaroo

Eastern Grey Kangaroo

The Eastern Grey Kangaroo is a marsupial found in southern and eastern Australia, with a population of several million. It is also known as the Great Grey Kangaroo and the Forester Kangaroo...

 and the Southern Hairy-nosed Wombat

Southern Hairy-nosed Wombat

The Southern Hairy-nosed Wombat is one of three species of wombats. It is found in scattered areas of semi-arid scrub and mallee from the eastern Nullarbor Plain to the New South Wales border area. It is the smallest of all three wombat species. The young often do not survive dry seasons...

, although many more (such as the Tammar Wallaby

Tammar Wallaby

The Tammar Wallaby , also known as the Dama Wallaby or Darma Wallaby, is a small member of the kangaroo family and is the model species for research on kangaroos and marsupials. It is found on offshore islands on the South Australian and Western Australian coast...

 have become extinct on the two peninsulas since they have been cleared for farmland. Birds include the emu

Emu

The Emu Dromaius novaehollandiae) is the largest bird native to Australia and the only extant member of the genus Dromaius. It is the second-largest extant bird in the world by height, after its ratite relative, the ostrich. There are three subspecies of Emus in Australia...

.

Threats and preservation

This is a heavily populated region and most of the area has been cleared for farmland resulting in reduced populations and local extinction of much wildlife, especially on Yorke Peninsula. However clearance has mostly ceased now and the northern areas of Eyre Peninsula in particular still have large areas of mallee woodland while the coastal dunes remain mostly unspoilt also. Weeds, fertiliser and herbicide runoff are still threatening habitats. Protected areas include Innes National Park

Innes National Park

Innes is a national park on the southwest tip of Yorke Peninsula in South Australia , 160 km west of Adelaide.-Environment:Innes is the largest area of native vegetation remaining on the Yorke Peninsula, providing habitat for 115 species of conservation significance...

on Yorke Peninsula.

Further reading

• Thackway, R and I D Cresswell (1995) An interim biogeographic regionalisation for Australia : a framework for setting priorities in the National Reserves System Cooperative Program Version 4.0 Canberra : Australian Nature Conservation Agency, Reserve Systems Unit, 1995. ISBN 0642213712