This study arose from a conservation dilemma between the need to conserve a population of the endangered pink tailed legless lizard, Aprasia parapulchella and crucial upgrading of Canberra's sewerage treatment plant. The study focused on conservation biology and how it could be applied to the management of A. parapulchella. As little biological information was available on A. parapulchella, research was focused on obtaining data that would be beneficial in the conservation management of the species. This included the dietary and habitat requirements, population status and structure and population relocation and habitat restoration. A. parapulchella was found to occur in low relative densities at all sites (maximum 9.1 lizards per 1000 rocks turned, Mt Taylor). Populations of the species appear to be larger than has been considered previously, however numbers are still below 500 individuals per site. Sexual dimorphism is present in the species with females achieving longer snout-vent lengths than males. Sex ratios were equal in all sites, however average size of lizards was different at the four main study sites, indicating differences in population structure. The life history of A. parapulchella can be summarised as long-lived, late maturing (3rd or 4lh year of life) with a low reproductive rate (single clutch of two eggs per year). A. parapulchella is a dietary specialist feeding on about 11 different species of ants. Interestingly, the lizards also live with the same species that they feed upon. By far the most important species in the diet and homesite requirements of A. parapulchella is the ant Iridomyrmex rufoniger. A. parapulchella shows positive selection towards the species in homesite choice, is found most commonly in the nests of this ant, and selects its brood over the brood of other ant species in diet experiments. In addition this ant was represented in the diet of A. parapulchella more commonly than any other ant. The relationship between ants and A. parapulchella appears to be unique and the mechanisms of this specialisation require further investigation. The vegetation associations where A. parapulchella occur are different across the range of the species. Sites at Bendigo and West Wyalong support mallee communities, while in the ACT region, Bathurst and Tarcutta, A. parapulchella appears to be a habitat specialist, being found most commonly in sites dominated by grass species, both native and introduced. A. parapulchella lives beneath rocks in grassland sites. Rocks that the species uses for homesites are commonly between 100 and 150 mm wide, 120-220 mm long and 50 and 150 mm thick. There were significant differences between the sizes of rocks used at different sites and between different seasons. Rocks used by females were significantly larger than rocks used by juvenile lizards. Twelve other species of reptile were found to use rocks in grassland sites, with rocks partitioned within the community on the basis of size and shape. An experimental relocation of A. parapulchella was conducted to try to determine ideal habitat conditions for the survival of relocated individuals. Unfortunately of the 114 lizards released, only 15 were recaptured. Although recaptures were low, trends indicated that treatments of Themeda triandra and very high rock densities had the highest survival rates. Key habitat variables were reinstated at the Lower Molonglo Dam site however restoration is preliminary with more time needed for the habitat to be suitable for occupation by A. parapulchella. What started as a situation that was likely to have a deleterious impact on A. parapulchella has been turned into a conservation success story. Without the involvement of ACT Electricity and Water, much of the basic biology of A. parapulchella would still be unknown. The findings will now form a solid basis from which to effectively conserve A. parapulchella. The project provides an example of the conservation success that can be achieved between industry and conservation partnerships.

This study examined the ant communities of several grasslands of the Australian Capital Territory (ACT) and their relevance to the pink-tailed legless lizard, Aprasia parapulchella (Pygopodidae). A. parapulchella is a fossorial species that shares burrows with, and eats the brood of, several grassland ant species. Foraging ants were collected from sites by pitfall trapping throughout one calendar year and comparisons of ant communities made between seasons and sites of differing vegetation structure. Competition between ant species for artificial nest sites and the effects of temperature on selection of nest site selection were also studied. The role that ants play in the distribution of A. parapulchella was investigated by (i) comparing ant faunas from several sites throughout the geographic range of the lizard, including sites in New South Wales and Victoria, (ii) performing feeding preference experiments with A. parapulchella, and (iii) investigating the seasonal nature of brood production and nest establishment by ants in ACT grasslands. Major findings were used to make recommendations to assist in the management, including rehabilitation, of A. parapulchella grassland sites. Low insolation appears to significantly affect the ant species composition of grassland sites in the ACT relative to other Australian vegetation types. In the ACT grassland sites, large species of the Dominant Dolichoderinae functional group were absent, or present only in very low numbers. The communities were species-poor relative to other Australian studies with only 60 species being recorded across all sites studied, with no more than 21 species recorded at any site on any sampling occasion. Whilst ant species community structure was highly variable between seasons and sites, more than 95% of ants were from the three functional groups, Dominant Dolichoderinae, Generalized Myrmicinae and Opportunists. The communities were numerically dominated throughout the year by the ubiquitous species groups Iridomyrmex 'rufoniger' and Rhytidoponera 'metallica'. Almost all taxa increased in foraging abundance during summer months and Pheidole spp., Monomorium spp., Crematogaster sp. Paratrechina sp. and Notoncus ectalomoides were occasionally locally abundant. There were no significant relationships between ant and vegetation community structures, but Solenopsis sp. showed an alliance with sites that had a high abundance of Themeda australis (kangaroo grass), whilst Crematogaster sp. and Paratrechina sp. are potential bioindicators of disturbance from grazing or pasture improvement. Iridomyrmex 'rufoniger' were the numerically dominant foraging ants, making up 50% of all captures, but they held only 80% of their nest sites when faced with competition from other species. R. 'metallica' and Pheidole spp. on the other hand, gained 80% more nests than they lost to other taxa. I. 'rufoniger' and R. 'metallica' both preferred nest sites with warmer temperature regimes when given the choice, and this assisted them to tend brood throughout the year. All ant species in ACT grasslands had summer peaks in brood production. Most nests were inactive throughout the cooler months and nest founding was predominantly between September and November. The common species, Iridomyrmex spp., Paratrechina sp. and R. 'metallica' held winged reproductives in their nests from April and all ant taxa had released all alates by mid- November. Although there were differences in ant community structure throughout the range of A. parapulchella, the ubiquitous R. 'metallica' and I. 'rufoniger' were always abundant, whilst again, Dominant Dolichoderinae and associated subordinate taxa were absent or present only in relatively low numbers. The lizards consumed brood from all the common ant species in ACT grasslands and showed preference for consuming brood of, and living with, small Iridomyrmex spp. The range of the small Iridomyrmex spp. preferred by A. parapulchella extends far beyond that of the lizard. Its distribution is apparently not restricted by the range of its ant prey species. For rehabilitation of A. parapulchella sites in the ACT, it is recommended that a significant ground cover of native grasses is established to ensure the low abundance of large and territorial ants from the Dominant Dolichoderinae functional group. Along with a high abundance of shallow surface rocks, this will ensure the establishment of ant communities that are numerically dominated by small Iridomyrmex spp., which are preferred by A. parapulchella for homesite sharing and as a food source.