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Environmental factors play an integral role, either directly or indirectly, in structuring faunal assemblages. Water chemistry, predation, hydroperiod and competition influence tadpole assemblages within waterbodies. We surveyed aquatic predators, habitat refugia, water height and water chemistry variables (pH, salinity and turbidity) at 37 waterbodies over an intensive 22-day field survey to determine which environmental factors influence the relative abundance and occupancy of two habitat specialist anuran tadpole species in naturally acidic, oligotrophic waterbodies within eastern Australian wallum communities. The majority of tadpoles found were of Litoria olongburensis (wallum sedge frog) and Crinia tinnula (wallum froglet) species, both habitat specialists that are associated with wallum waterbodies and listed as Vulnerable under the IUCN Red List. Tadpoles of two other species ( Litoria fallax (eastern sedge frog), and Litoria cooloolensis (cooloola sedge frog)) were recorded from two waterbodies. Tadpoles of Litoria gracilenta (graceful treefrog) were recorded from one waterbody. Relative abundance and occupancy of L. olongburensis tadpoles were associated with pH and water depth. Additionally, L. olongburensis tadpole relative abundance was negatively associated with turbidity. Waterbody occupancy by C. tinnula tadpoles was negatively associated with predatory fish and water depth and positively associated with turbidity. Variables associated with relative abundance of C. tinnula tadpoles were inconclusive and further survey work is required to identify these environmental factors. Our results show that the ecology of specialist and non-specialist tadpole species associated with 'unique' (e.g. wallum) waterbodies is complex and species specific, with specialist species likely dominating unique habitats. [ABSTRACT FROM AUTHOR]

Abstract It is generally accepted that high quality males are those that succeed in male-male competition: in either aggression or rivalry to attract and be selected by females. Previous studies of amphibians have suggested that the main characters influencing male mating success include variation in call characteristics (e.g. call rate, call intensity), calling behaviour, body condition, age and chorus tenure. In the present paper, several of the characters influencing female mate choice (male body size, body condition, call rate, call frequency and chorus tenure) are investigated in two closely related, explosive breeding frog species Litoria chloris and Litoria xanthomera. Smaller males of both species are shown to be more successful than larger males and this success is attributed to the increased chorus tenure of smaller males in L. xanthomera. This increased chorus tenure was attributed to the lower total energy used per call by a small male calling at a higher frequency. Whether increased chorus tenure explains female mate choice in L. chloris is uncertain but is highly probable given the strong similarity between the two species in both ecology and call characteristics. [ABSTRACT FROM AUTHOR]

Abstract We investigated the influence of native flora and fauna on the establishment and persistence of the exotic weed Ageratina riparia (Asteraceae) in disturbed and regenerating rainforests on the Springbrook plateau of south-eastern Queensland. The height and ground cover of A. riparia was positively associated with light availability beneath the rainforest canopy and negatively associated with forest leaf litter biomass. Regenerating rainforest with the associated increases in litter and decrease in light availability could therefore inhibit the establishment and density of A. riparia. The red-necked pademelon, Thylogale thetis, browsed extensively on A. riparia, but the pattern of browsing was not associated with light availability, forest leaf litter biomass or density of A. riparia. Browsing and incidental damage by T. thetis breaks up the broad stands of A. riparia. The physical damage caused by T. thetis, and the inhibition to establishment and density of A. riparia by native plant species, combine to reduce the environmental threat associated with A. riparia. [ABSTRACT FROM AUTHOR]