Recovery plan for the Nangur spiny skink (Nangura spinosa)

Summary

Species and status

The Nangur spiny skink or Nangur skink Nangura spinosa is a medium-sized spinose lizard, belonging to the family Scincidae. It is listed as ‘Critically Endangered’ under the Commonwealth Environment Protection and Biodiversity Conservation Act 1999, 'Endangered' under the Queensland Nature Conservation Act 1992 and it is ranked as a medium priority under the Department of Environment and Resource Management ‘Back on Track’ species prioritisation framework.

Habitat and distribution summary

N. spinosa was first discovered by Europeans in 1992 (Covacevich et al. 1993) with the second population found approximately 38 km away in 1997 (Hannah et al. 1997). The skink is restricted to these two locations in south-east Queensland. Current estimates suggest a total population size of 183 adults with an extent of occurrence of approximately 45 km² (Borsboom et al. 2005). Targeted surveys are underway to assess whether the skink occurs in other areas of suitable habitat.

The species has been recorded on gentle sloping banks in semi-evergreen vine thicket on black basaltic soils (Covacevich et al. 1993). It has also been found on clay slopes in araucarian notophyll/microphyll vine forest and hoop pine (Araucaria cunninghamii) plantations (Hannah et al. 1997; Borsboom et al. 2005). At one site, the skinks showed a preference for road embankments, where more burrows were observed than on open ground (Borsboom et al. 2005). The skinks generally occur at altitudes of 315–600m (Department of the Environment, Water, Heritage and the Arts 2009).

Threats summary

Habitat clearing and the establishment of hoop pine plantations were probably significant historical threats to N. spinosa. A number of potential current threatening processes have been identified. These include inappropriate fire regimes, weed invasion, introduced predators (cane toads, foxes, pigs and cats), hoop pine harvesting and re-establishment, and illegal collecting. Management options aimed at ameliorating these threats are discussed.

Recovery objective

The objective of this recovery plan is to improve the status of N. spinosa populations in the wild by implementing informed management decisions based on a thorough understanding of the species’ biology and habitat requirements.

Summary of actions

The key actions required to promote the recovery of N. spinosa populations include:

• conduct surveys to determine the full extent and area of occupancy of the skink;
• undertake genetic comparison of the two known populations;
• monitor weed impact and where feasible initiate, continue and/or expand appropriate weed control (e.g. lantana) measures;
• monitor feral animal impact and where feasible initiate, continue and/or expand appropriate feral animal control measures;
• monitor illegal collection and disturbance activities;
• continue and expand N. spinosa population monitoring programs; and
• monitor ecological and biological parameters considered important for the survival of the wild populations and for implementing effective management practices.