Research

Northern Whip-tailed Skink Tropidoscincus boreus

Conservation status: Lower risk - least concern

Description: A moderately large species of skink growing to a body length of 78 mm, with very well developed limbs and a long tail 250% of the body. The scales of the body have three distinct keels. Adult colouration is dark overall with an orange ventral colour, but juveniles and sub-adults have distinctive yellow markings running along the side of the body.

Natural distribution: A widespread but scattered distribution in the central, northern, and ranges ultramafic ranges of the west coast of New Caledonia. The species occurs in closed forest habitat and maquis shrubland.

Maquis shrubland - low and heath-like vegetation
Ultramafic - rocks that are dominated by minerals high in magnesium and iron, and which tend to be dark-coloured rather than pale.

Distribution within Province Nord: Restricted to Province Nord - see natural distribution.

Threats:

• potentially high level of threat to closed forest populations with high infestation levels of introduced Fire Ants (Wasmannia auropunctata) causing significant decline in abundance
• moderate to potentially high level of threat to high elevation maquis and closed forest on ultramafic soils through activities associated with mining (particularly gully forests affected by mining spoil) on the west coast, resulting in a decline in area, extent and quality habitat
• moderate to potentially high level of threat to populations in maquis shrubland or remnant closed forest on the west coast through repeated firing, resulting in a decline in quality of habitat
• low level of threat to low elevation closed forest on the east coast from clearing for subsistence agriculture resulting in loss and further fragmentation of habitat
• low level of threat to closed forest edge through repeated firing of adjacent savannah habitat resulting in a decline in area, extent and quality of habitat
• low level of threat to mid elevation forest for timber plantations resulting in a decline in area, extent and quality habitat

Conservation status: Tropidoscincus boreus occurs at 10 sites representing up to eight sub-populations over the south of the island. The known distribution of the species just satisfies the criteria for a small distribution (area of occupancy <1,000 km2), but it is considered to be more widespread in the central ranges than available information indicates. Further survey work is likely to increase the number of locations where Tropidoscincus boreus is found. Several threats leading to a continuing decline in closed forest habitat have been identified above, but large areas of potentially suitable habitat subject only to minimal or no disturbance occur within the species range. For these reasons T. boreus is most appropriately categorised as lower risk - least concern, and is not considered to be under any immediate threat.

Future research required:

• general survey work to more comprehensively document the species overall distribution, particularly in closed forest in the central ranges
• identification of distinct geographic units

Copyright © Australian Museum, 2002