Document ID: chunk:federal_register_of_legislation:F2007B00384:body:0:p5
Version: federal_register_of_legislation:F2007B00384
Segment Type: other
Provision Reference: 
Character Range: 11276–14144

plan.  This necessitates careful attention to inclusion of Asplenium listeri in environmental assessments and management standards across the island, regardless of specific tenure.

The magnitude of any potential constraint cannot be estimated, as it will vary with the location, size and extent of an affected population, and the nature and extent of the activity, proposed or current.

Actions arising from this plan that may have some potential to constrain economic activity or development include:
    * possible future addition of areas to the Christmas Island National Park specifically to protect an occurrence of Asplenium listeri
    * possible identification of Asplenium listeri as an element in the heritage values or attributes of a place on the Register of the National Estate or a future heritage listing under the EPBC Act; and
    * possible future addition of areas to the Register of Critical Habitat established under the EPBC Act, affording an additional layer of protection under that Act in Commonwealth areas.

PART B: DISTRIBUTION AND LOCATION

B.1 Distribution

B.1.1 Christmas Island - overview

Asplenium listeri is known only from Christmas Island, a territory of the Commonwealth of Australia, located in the Indian Ocean at about 10°25'S and 105°40'E.  The island lies approximately 2,600 kilometres west of Darwin and 360 kilometres south of Jakarta and the western end of Java.  The island covers approximately 135 square kilometres (13,500 hectares), of which about
85 square kilometres (8,500 hectares) (63%) is gazetted as Christmas Island National Park, a Commonwealth reserve under the EPBC Act.

The island is formed on the peak of a volcanic mountain which rises steeply about 5,000 metres from the ocean floor.  Successive layers of coral reefs were formed over the igneous core at each stage of its emergence from the ocean, leading to development of a near‑continuous limestone cap.  As the island became raised above sea level the ocean excavated new cliffs at each stage, leading to a topography of stepped terraces and inland cliffs.

Most of the coast consists of sheer rocky cliffs 10 to 20 metres high, often undercut, with a few beaches of sand and coral rubble.  The interior comprises an irregular plateau from 160 to 360 metres elevation, separated from the coast by a series of steep slopes or cliffs with narrow terraces between.  Across the island, substrates are almost entirely derived from limestone, with deep soils on the plateau and upper terraces, becoming progressively thinner and drier towards the more rocky lower terraces.

The island experiences a tropical equatorial climate, with a mean annual rainfall of 2,110 millimetres, reduced during years when the El Niño effect is in operation.  The tropical climate leads to a marked seasonality in rainfall, with the dry season from May to November