Ecotones have been considered as unique environments, and the concepts of edge effect and ecotonal species have been widely used, especially in avian community ecology. We studied the patterns of bird densities across heath-wood edges at replicated sites in three locations in southeastern Australia. Multivariate analysis showed that the bird community in the ecotone was intermediate between the heath and wood communities, indicating that the ecotone contained a mixing of species rather than a unique bird community. ANOVA showed a modest increase in bird density at the wood side of the ecotone, which may be partly due to sampling biases rather than to some inherent habitat value in the ecotone. The outstanding pattern was that bird density and species richness in the wood habitat were twice as high as in the heath habitat. Of a total of 86 species, 31 occurred in sufficient numbers to categorize according to their habitat association (generalist, or heath or wood specialist) and their density at the ecotone (ecotone neutral, ecotone shy, or ecotone conspicuous). Three of these were habitat-generalist-ecotone-neutral. Fourteen species were ecotone neutral but were habitat specialists on either the wood (13 spp.) or the heath (1 sp.). Three species were ecotone shy. Although 11 species were ecotone conspicuous, they also occurred in either heath or wood or both. Thus, no species could be categorized as entirely ecotonal. We conclude that there is little evidence from this or other studies of avian communities to support an edge effect of increased density and species richness, and no evidence of entirely ecotonal species.

The distribution of many plant species will change with global climate change, depending on their ability to disperse into, and establish in, new communities. Past migrations of species under climate change have been an order of magnitude slower than the rate of predicted climate change for the next century. The limited evidence available suggests that chance long distance dispersal events will be critically important in determining migration rates. The JABOWA-derived gap replacement models and vital attributes/FATE models were examined, and the dispersal and establishment processes necessary to make improved projections of vegetation dynamics under climate change using these models were investigated. The minimum modifications of these models required to incorporate directional migration of species are described. To predict establishment success of species, it was suggested that a more fundamental understanding is needed of how establishment ability under different conditions relates to seed and seedling attributes and how this may be affected by elevated CO2. Finally, an examination was carried out of whether plant functional types based on vegetative attributes (used to model the response of adult plants) are correlated with functional types based on seed and seedling attributes. Available evidence suggests that the two sets of attributes are not strongly correlated; consequently, models of vegetation dynamics will need to incorporate seed biology explicitly.

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Context Risk assessments currently undertaken to approve pesticides for use against locusts in Australia are predominated by laboratory-generated data, often collected from non-endemic species. Very little information exists concerning the potential ecological effects of insecticides used for locust control. Aim To determine the effect of aerial ultra-low volume (ULV) applications of the organophosphorous insecticide, fenitrothion (used for locust control), on avian assemblages in arid and semiarid agro-ecosystems. Methods Avian abundance was surveyed in pesticide-exposed and unexposed locations during standard locust control operations, using fenitrothion, in western New South Wales and Queensland in the spring and summer of 1996, 1997 and 2000, using a transect-point method. Temporal changes in assemblages were analysed using multi-dimensional ordination (MDS) and permutational analysis of variance (PERMANOVA) with PRIMER (V7). Key results Avian assemblages varied over time, independent of pesticide application, reflecting significant redistribution and mobility of birds across a highly disturbed agricultural landscape, irrespective of pesticide exposure. Additionally, pesticide exposure did not affect species abundance or diversity. Conclusions There was no evidence that ultra-low volume (ULV) applications of fenitrothion, currently used in locust control, are impacting avian assemblages, despite previous research indicating that individual birds co-occurring with spray operations suffer suppressions in the enzymatic biomarker for OP exposure, plasma acetylcholinesterase (AChE). Implications Although the risk to avian assemblages associated with the aerial application of locusticides is reduced by the small proportion of the landscape where locust control activities are focused, any change in spray application parameters would necessitate a re-evaluation of the risks associated with insecticide exposure.

Harry is the sort of person you always remember once yau have met him. You don't forget the wicked smile nor the sense of being challenged when you hear him speak. Perhaps one of Harry's greatest contributions to ornithology in Australia has been the fact he has never walked away from any argument, whether it be with land managers who are poorly managing bird populatians, scientists who have done poor science, or with conservationists who have not thought through their values and aspirations. Harry makes you think, and he has made ornithologists think.Harry Recher began studying as an undergraduate at the State University of New York, College of Forestry, and then at Syracuse University. He completed his PhD under Paul Ehrlich at Stanford University (California). After receiving this degree in 1964, he held postdoctoral positions at the University of Pennsylvania and then at Princeton University, where he worked with the late Robert Macarthur. With a background in the community ecology of birds, he made his way to Australia in 1967 and took up an appointment as lecturer at the University of Sydney. The following year, he was appointed research scientist at the Australian Museum. He stayed at the museum for 20 years, paying particular attention to conservation issues and the biology of forest birds. In 1988, he joined the Department of Ecosystem management at the university of New England, where he is currently an associate professor.Harry's interest in forest birds has been longstanding. He has contributed to our knowledge of the-effects of both fire and logging on forest bird communities. He has developed, tested and evaluated bird census techniques in these habitats, and provided valuable information for land managers, scientists and bird watchers. He has been deeply concerned about the effects of logging' on bird communities and has always been extremely involved in campaigning for better forest management practices. At the present time, Harry is involved with a variety of research projects that address the role of corridors in the conservation and management of forest bird communities, the relationship between insect abundance and foliage structure on foraging by foliage gleaning birds, the ecology of forest owls and post-fire recolonisation by birds. These contributions make Harry one of the leading experts in Australia on forest bird communities. His interests have not been restricted to forest bird communities because he has also studied other species such as herons, egrets and heathland birds.Harry has published over 140 scientific papers, covering many aspects including avian ecology and conservation.