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)

10.2. Reference number WA2

Refuge area: Monte Bello Islands

Biogeographic region: Pilbara

Type of refuge: Islands

Lat./Long. 20°28’S / 115°31’E

Quality of refuge: Highly significant (4)

Area (km²): <1,000

Chief refuge value

Isolation from land use changes and feral animals of adjacent mainland.

General description

A group of c. 200 islands of coastal limestone 80 km off Cape Preston in north-west Australia5. Major islands are Hermite, Trimouille and North West Islands. The largest is Hermite (10.1 km²). The larger islands have highly indented coastlines so that no part of the island is more than 1 km from the sea. Hermite has rocky hill tops and areas of flat dried mud. Trimouille has large areas of almost bare sand. Most islands are rimmed by low cliffs 2-3m tall. Mangroves accur in sheltered bays. The dominant vegetation is Triodia hummock grassland with low shrubs, tussock grasses and herbs growing in gullies1.

ANZECC-listed species

Hawksbill Turtles Eretmochelys imbricata (V) nest in small numbers3. The Monte Bello islands (Trimouille, North-west Islands) are a very significant rookery for green turtles Chelonia mydas (E)3. There is one record of leatherback turtles Dermochelys coriacea (V) coming ashore on Trimouille Island3.

Regional endemics

The Hermite Island worm-lizard Apraisia rostrata rostrata2, 4.

Relict species

None identified.

Other significant species

Water rat Hydromys chrysogaster on Hermite Island2.

Key threats

Feral cats on Hermite and Trimouille Islands, and black rats Rattus rattus present on most islands1. Possible disturbance from humans in future4.

Land tenure

Recently transferred from Commonwealth to State control.

Key references

1. Burbidge (1971a)

2. Burbidge (1989)

3. Prince (pers. comm.)

4. Cogger et al. (1993)