Biodiversity publications archive

Refugia for biological diversity in arid and semi-arid Australia

Biodiversity Series, Paper No. 4
S.R. Morton, J. Short and R.D. Barker, with an Appendix by G.F. Griffin and G. Pearce
Biodiversity Unit
Department of the Environment, Sport and Territories, 1995

10. Refugia in Western Australia (continued)

10.8. Reference number WA8

Refuge area: Bernier and Dorre Islands

Biogeographic region: Carnarvon

Type of refuge: Islands

Lat./Long. 24°52’S / 113°08’E; 25°06’S / 113°06’E

Quality of refuge: Extremely significant (8)

Area (km²): <100

Chief refuge value

Refuge for endangered mammals.

General description

Long, narrow, uninhabited islands 50-60 km off the coast of Shark Bay. Both islands are flat plateaux girded by cliffs on all sides with major landforms of sandplain, consolidated dunes, unconsolidated dunes and travertine rock. Bernier is 44 km²; Dorre is 53 km².

ANZECC-listed species

Burrowing bettong Bettongia lesueur, rufous hare-wallaby Lagorchestes hirsutus, banded hare-wallaby Lagostrophus fasciatus, western barred bandicoot Perameles bougainville, and Shark Bay mouse Pseudomys fieldi (Bernier only) (all E).

Regional endemics

Mammals: Water rat Hydromys chrysogaster on Dorre Island6.

Birds: Variegated fairy-wren Malurus lamberti bernieri common and endemic to Bernier and Dorre Islands7.

Reptiles: Dragon Typanocryptis parviceps (Bernier Island), gecko Diplodactylus rankini (Bernier Island and extreme north of east zone, and the skinks Ctenotus youngsoni (endemic to Dirk Hartog Island and Edel Land, including Salutation and Three Bays Islands) and Egernia bos (confined to Bernier Island).

Plants: Beyeria cyanescens (also Dirk Hartog Island), Cryptandra nudiflora and Goodenia ochracea3.

Relict species

"One third of the 30 plant species confined to Shark Bay are restricted to islands, a further example of how islands can shelter relict populations"8. The ANZECC-listed species are all relictual populations following their extinctions on the mainland.

Other significant species

Turtles may nest on the islands in small numbers8.

Key threats

Introduction of exotic species, particularly foxes and cats.

Land tenure

Nature reserves.

Key references

1. Ride et al. (1962)

2. Robinson et al. (1976)

3. Keighery (1990)

4. Keighery and Trudgeon (1991/2)

5. Short and Turner (1992, 1993)

6. Friend and Thomas (1990)

7. Storr (1990)

8. Morris et al. (1991/2)