This study describes the floristics and structure of a 0.95-ha lowland tropical rainforest plot at the Australian Canopy Crane Research Facility at Cape Tribulation, Queensland. Five years of post-cyclonic change in forest floristics and structure following the passage of Tropical Cyclone 'Rona' in February 1999 are examined. Local and regional variation in tropical rainforest is examined in comparison with other lowland plots established nearby and mid-elevation plots located elsewhere in north Queensland at Eungella, Paluma and the Atherton Tablelands.These plots are placed in a broader Australasian context along with lowland rainforest plots at Baitabag and Oomsis, Papua New Guinea.The 2005 survey found 680 stems of 82 species Ն10 cm d.b.h. on the crane plot, an increase of 30.3% in stems and 16.4% of species in the 5 years since the previous survey. The most abundant families were Meliaceae, Euphorbiaceae, Lauraceae, Myrtaceae and Apocynaceae and the most abundant species were Cleistanthus myrianthus, Alstonia scholaris, Myristica insipida, Normanbya normanbyi and Rockinghamia angustifolia. Temporal floristic and structural variation suggests that the crane site remains in an active stage of post-cyclonic recovery. Local spatial variability in floristics and structure at Cape Tribulation exceeded the variation exhibited by a single plot over a period of 5 years, despite the impact of Cyclone Rona. This finding suggests a high degree of temporal stability within this stand of rainforest despite frequent catastrophic disturbances. The rainforests of Cape Tribulation constitute a relatively unique floristic community when observed in an Australasian context. Variation in rainforest community composition across the region shows the importance of biogeographical connections, the impacts of local topography, environmental conditions and disturbance history.

The pollination biology of Syzygium sayeri was documented using the special capabilities of the Australian Canopy Crane. Syzygium sayeri is a xenogamous species with poor self-compatibility, moderate levels of natural out-crossing, and the producer of copious amounts nectar throughout the day and night. Of a diverse fauna associated with, and visiting the flowers of S. sayeri , larger vertebrates (blossom bats and honeyeaters) account for approximately half its natural pollination rate, while the balance of pollination is attributable to a host of invertebrate visitors (wasps, flies, thrips, butterflies). Day and night pollinators contributed approximately equally to the successful pollination of S. sayeri ; although the number of individuals visiting flowers was greater during the day, further experimentation might reveal night visitors to be more effective pollinators. The co-occurrence of vertebrates and invertebrates, as well as day and night visitors, suggests that S. sayeri has a generalist pollination system, whereby the absence of a discrete set of faunae could be compensated for by the presence of other pollinators. What is not clear is the contribution of different pollinators to the population success (i.e. gene flow) of this species. Further study is needed to determine the contribution of each pollinator group to the flow of genetic material in populations of S. sayeri .

Canopy crane-based studies have been carried out to quantify the sets of arthropods that visit the flowers of a suite of common species of trees, palms and vines within the Cape Tribulation study area.Those Orders that increase significantly in abundance between the budding and flowering stages of inflorescences are identified, and multivariate and univariate comparisons have been made first, among coflowering plant species and second, at different seasons for the same plant species. The analysis has been repeated for both the profile of higher arthropod taxa in the samples and for the relative abundances of families of Coleoptera: one of the Orders most frequently suggested as critical in the pollination biology of Australian rainforests. In all cases significant differences are identified among species confirming that the visitor profile is a plant species-specific phenomenon. Profiles within plant species at different times also differed. At the ordinal level significant differences in visitor profiles associated with coflowering plants, were observed, variously, in Thysanoptera, Diptera, Lepidoptera, Coleoptera and Hymenoptera. Within the Coleoptera significant differences occurred in relative abundances of Scarabaeidae, Phalacridae, Latridiidae and Curculionidae. Seasonal differences in visitation to Syzygium gustavioides, Normanbya normanbyi and Calamus radicalis, reflected differences in Diptera, Lepidoptera, Homoptera, Thysanoptera, Hymenoptera and Araneida. Within the Coleoptera, the Elateridae and Curculionidae varied significantly between occasions.The various forms of flower/arthropod interaction that may be represented in these results are discussed, as are the implications for pollination.

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Reptile assemblages were examined retrospectively in relation to five age categories of regrowth since the last selective tree harvest (i.e., 0-10 years, 11-20 years, 21-40 years, 41-50 years and >50 years/ virgin). The aim was to identify indicator species that showed consistent response to post-harvest forest regrowth. A total of 47 reptile species were recorded from 95 systematically surveyed sites. Species richness was lower in 11-20 years old regrowth with no effect observed in regrowth aged 40-50 years. This trend was not significant. Reptiles overall, and a subset of 'common' reptiles, were significantly less abundant in 11-20 year regrowth compared to the 0-10 years regrowth. Abundance of reptiles was not significantly higher in older forests (i.e., 41-50 years since harvest and >50 years or virgin sites) than in forests within the 11-40 years since harvest period. The trends in abundance observed amongst all reptiles and common reptiles were largely due to the numbers of skinks. In general, skink abundance was significantly lower in the 11-20 years since harvest period and highest in the first ten years after harvesting. A majority of these skinks belonged to a guild of bark-, log-and rock-dwellers. High shrub density in the 11-20 year old regrowth provides some explanation for lower numbers of skinks recorded. Shrub density may affect the availability of basking sites for reptiles at ground level and the accessibility and searching behaviour of observers. Ambient temperature at the time of survey had a significant effect on the abundance of some skink species, which meant that an explanation was confounded. The common "bark-, log-and rock-dwelling" skinks, Lampropholis spp. and Carlia spp. demonstrated measurable changes to measurable habitat conditions and disturbances, which are traits of model "indicator" species. The limitations of using common skinks as indicator species are acknowledged and a caution is issued in respect to inappropriate use of the species indicator tool.