969 resultados para Territories


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Although 90% of passerine birds live in socially monogamous pair bonds, molecular studies have revealed that genetic polygamy occurs in 86% of surveyed passerines, because individuals engage in copulations outside the pair bond (extrapair copulations; EPCs). Most explanations for the occurrence of EPCs involve female gaining indirect benefits from the extrapair male. The sedge warbler is a socially monogamous species in which some offspring result from EPCs (8% in this study). Complex song is a sexually selected male trait used by females which select mates based on a variety of male qualities. We used microsatellite DNA profiling to detect extrapair young and assign paternity. ‘Good genes’ theory predicts that females should engage in EPCs with males of higher quality than their social mate, with resulting fitness benefits. Extrapair males had smaller song repertoires and smaller territories than the social mate. This apparent preference for small-repertoire males as extrapair mates conflicts with the predictions from previous studies of this species. Sudden cessation of song after pairing may mean that song cues are unavailable for later extrapair matings and females may switch to other cues. Such behaviour may lead to different patterns of female choice during social and extrapair mating in the sedge warbler. We conclude that multiple reasons underlie patterns of female choice in this species.

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The establishment of a comprehensive, adequate and representative (CAR) reserve system is not only an objective of all States and Territories but it is an international commitment, since Australia signed the Convention on Biological Diversity. Various reviews note that Australia lacks a representative freshwater reserve system. However, there has been surprisingly little quantitative analysis on the reservation of freshwater ecosystems from which to identify the gaps or deficiencies in the reserve system.

We compared aspects of reservation in wetlands in northern Victoria before and after a major public land use investigation by the government-appointed Victorian Environmental Assessment Council, which sought specifically to recommend a CAR reserve system. Significant improvements in the reservation status for depleted and under-reserved wetland ecosystems, and improved reserve design have been recommended by the investigation. Increases in the reservation of nationally and internationally significant wetlands were also recommended. These recommendations are now under consideration by the Victorian Government.

Some of the challenges in decision-making during this investigation and their implications on wetland conservation are highlighted. The paper concludes by outlining broader policy dilemmas, decisions and debates that that require addressing in relation to developing a system of Freshwater Protected Areas in Australia.

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With the proliferation of Indigenous texts currently published by specialist and mainstream publishers, non-Indigenous editors increasingly find themselves negotiating the uncomfortable territories of race, politics and power for which current training (in an Australian context) leaves them poorly prepared. Indigenous writer Anita Heiss advocates the employment of Indigenous editors as an 'ideal' solution, though few are currently working in the Australian industry. Margaret McDonell, an experienced non-Indigenous editor of Indigenous texts, suggests non-Indigenous editors need to 'undertake a journey of learning' during which 'assumptions, biases, tastes and preconceptions' are examined. Yet this presents a difficult task within a postcolonial society, when, as identified by Clare Bradford, even the classification of texts into genres such as fiction and the short story represents an entirely Eurocentric construct, 'not readily correspond[ing] with Aboriginal schemata'. The Australian Society of Authors' discussion paper 'Writing about Indigenous Australia: Some Issues to Consider and Protocols to Follow' provides practical guidelines that may be adapted for editorial use. This article canvasses these and other ideas with a focus on establishing an ethical and appropriately sensitive cross-cultural approach to editing Indigenous writing.

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An understanding of space use and dispersal of a wildlife species is essential for effective management. We examined the movements of a beach-dwelling, threatened population of hooded plover (Thinornis rubricollis) in southern central Victoria, Australia, by analysing sightings of colour-banded birds (4897 sightings; 194 birds tracked for up to 9 years). Most movements were relatively short (5050 ± 305 m), with 61.4% <1 km and 95.3% <20 km; they lacked directional or sexual bias. The extent of coastline used by individual birds was 47.8 ± 58.0 km. Regional differences in average distances moved by adults were apparent. For adults, movement rates (mean distance per day) were higher during the non-breeding season than during the breeding season. Non-breeding adults generally remained close to their partners (non-breeding, 456.3 ± 163.9 m; breeding, 148.2 ± 45.3 m). Largest flock sizes were recorded during the non-breeding period, and flocking was not uniformly distributed along the coast but appeared to be concentrated in particular locations. The frequency of pair cohesion (i.e. when the distance between partners was zero on a given day) was similar during the breeding (69.6%) and non-breeding seasons (67.7%). Breeding territories (kernel analysis) were 36.7 ± 5.7 ha and overlapped from year to year in all cases (23 pairwise comparisons; 47.9 ± 7.1% overlap). The high fidelity and constancy of territories confirms they warrant ongoing management investment, although the species relies on a matrix of breeding and non-breeding sites. The latter appear to occur in specific parts of the coast and warrant enhanced protection and more research attention. Fragmentation of the breeding population might occur where habitat is rendered unsuitable for > ~50 km.

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Four decades ago Australia was credited as being an early leader in  implementing integrated coastal management (ICM). Nevertheless, as a  federation of states and territories Australia has since struggled to fully  implement vertical integration of its coastal governance arrangements. In particular the federal government has historically possessed only a minor role in coastal management despite the recommendations of several major inquires suggesting that this role needed to be enhanced. This article examines a series of circumstances and events over the past two years in Australia that has created the opportunity for the federal government to adopt a more significant and prominent role in coastal management and hence to substantially complete the vertical integration of ICM in Australia. These stimuli for coastal policy reform could also play a role in enhancing ICM in other federated nations.

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Apostatic (frequency‐ or density‐dependent) selection, aposematic signals, and mate choice behavior generally require that the mean prey or potential mate density m value be high enough (above a threshold T) to result in sufficient encounter rates for the searcher to learn or retain the association between conspicuous signals and prey unprofitability, to forage apostatically, or to choose among mates. This assumes that all searchers experience , which implicitly assumes an even dispersion of targets among searcher territories. Uneven dispersion generates new phenomena. If , then only territories with local density x values that are greater than T favor experience‐based behavior, leading to spatially variable frequency‐ or density‐dependent selection intensity. As aggregation increases, the increase in percentage of targets in favorable territories ( ) is greater than the increase in the percentage of territories that are favorable. The relationship is reversed when . In both cases, because as few as 10% of the territories can contain 80% of the targets, only a few territory holders may account for most of the selection on most of the target population; accidents of experience in only a few searchers can have unexpectedly large effects on the target population. This also provides an explanation for high searcher behavior variation (personalities) : individuals from favorable territories will behave differently in behavioral experiments than those from unfavorable territories, at least with respect to similar kinds of targets. These effects will generate spatial heterogeneity in natural and sexual selection in what are otherwise uniform environments.

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The White-browed Treecreeper Climacteris affinis is one of many woodland-dependent birds that are at risk from the encroachment of human-dominated land-uses into natural landscapes. The White-browed Treecreeper inhabits semi-arid woodlands in north-west Victoria, Australia, a vegetation community that has undergone extreme modification in the last century due to the expansion of agriculture in the region. Extant woodlands represent only 10% of the original woodland cover in the region, and are highly fragmented and disturbed in many districts. Thus, the survival of the White-browed Treecreeper may depend on active management. However, current knowledge of the ecology and biology of this species is virtually non-existent, and inadequate for informed and effective conservation actions. The aim of this thesis is to redress this situation and provide the ecological basis for sound conservation management of the species. The thesis consists of two parts: an investigation of habitat use at three spatial scales and a study of the social organization, nesting requirements, breeding behaviour and reproductive success of a population of White-browed Treecreepers. Fifty-six patches of remnant woodland in north-west Victoria were surveyed to determine the factors affecting the occurrence of the White-browed Treecreeper at the regional scale. It was detected in 16 patches, and was largely confined to two core districts - Yarrara and, Wyperfeld (Pine Plains). The floristic composition of the dominant tree species was an important determinant of patch occupancy, with the results providing quantitative support for the previously suspected affinity for Belah Casuarina pauper and Slender Cypress-pine Callitris gracilis — Buloke Allocasuarina luehmannii woodlands. However, the absence of the White-browed Treecreeper from several districts was due to factors other than a lack of appropriate habitat. Demographic isolation - the distance from the focal patch to the nearest population of the White-browed Treecreeper - was the most important variable in explaining variation in patch occupancy. Patches isolated from other treecreeper populations by more than 8.3 km in landscapes of non-preferred native vegetation, and 3 km in agricultural landscapes, were unlikely to support the White-browed Treecreeper. The impact of habitat loss and fragmentation on the capacity of individuals to move through the landscape (i.e. functional connectivity) is considered in relation to disruption to dispersal and migration, and the potential collapse of local metapopulations. Habitat use was then examined in a network of patches and linear strips of Belah woodland embedded in a predominantly cultivated landscape. A minimum area of 18.5 ha of Belah woodland was identified as the most important criterion for patch occupancy at the local scale. This landscape appeared to be permeable to movement by the White-browed Treecreeper, facilitated by the extensive network of linear habitat, and clusters of small to medium fragments. The third scale of habitat use investigated the frequency of use of 1-ha plots within tracts of occupied woodland. It is important to discriminate between habitat traits that operate at the population level, and those that act as proximate cues for habitat selection by individuals. Woodlands that have high tree density, extensive cover of low-stature shrubs, abundant lichen, a complex vertical structure, and relatively low cover of grass and herbs are likely to support larger populations of the White-browed Treecreeper. However, individuals appeared to be using tree dominance (positive) and tall shrub cover (negative) as proximate environmental stimuli for habitat selectivity. A relatively high cover of ground lichen, which probably reflects a ground layer with low disturbance and high structural complexity, was also a reliable indicator of habitat use. Predictive models were developed which could be used to plan vegetation management to enhance habitat for the White-browed Treecreeper. The results of the regional, landscape and patch-scale investigations emphasise that factors operating at multiple spatial scales influence the suitability of remnant vegetation as habitat for the White-browed Treecreeper. The White-browed Treecreeper is typical of many small Australian passerines in that it has high annual survival, small clutches, a long breeding season, multiple broods and relatively low reproductive rates. Reproductive effort is adjusted through the number of clutches laid rather than clutch size. They occupy relatively large, all-purpose territories throughout the year. However, unlike many group territorial birds, territory size was not related to the number of occupants. The White-browed Treecreeper nests in tree hollows. They select hollows with a southerly orientation where possible, and prefer hollows that were higher from the ground. At Yarrara, there was considerable spatial variation in hollow abundance that, in concert with territorial constraints, restricted the actual availability of hollows to less than the absolute abundance of hollows. Thus, the availability of suitable hollows may limit reproductive productivity in some territories, although the magnitude of this constraint on overall population growth is predicted to be small. However, lack of recruitment of hollow-bearing trees would increase the potential for hollow availability to limit population growth. This prospect is particularly relevant in grazed remnants and those outside the reserve system. Facultative cooperative breeding was confirmed, with groups formed through male philopatry. Consequently, natal dispersal is female-biased, although there was no skew in the sex ratio of the fledglings or the general adult population. Helpers were observed performing all activities associated with parenting except copulation and brooding. Cooperatively breeding groups enjoyed higher fledgling productivity than simple pairs, after statistically accounting for territory and parental quality. However, the difference reflected increased productivity in the 1999-breeding season only, when climatic conditions were more favourable than in 1998. Breeding commenced earlier in 1999, and all breeding units were more likely to attempt a second brood. However, only breeders with helpers were successful in fledging second brood young, and it was this difference that accounted for the overall discrepancy in productivity. The key mechanism for increased success in cooperative groups was a reduction hi the interval between first and second broods, facilitated by compensatory reductions in the level of care to the first brood. Thus, females with helpers probably achieved significant energetic savings during this period, which enabled them to re-lay sooner. Furthermore, they were able to recommence nesting when the fledglings from the first brood were younger because there were more adults to feed the dependent juveniles. The current utility, and possible evolutionary pathways, of cooperative breeding is examined from the perspective of both breeders and helpers. Breeders benefit through enhanced fledgling productivity in good breeding conditions and a reduction in the burden of parental care, which may impart significant energetic savings. Further, breeders may facilitate philopatry as a means for ensuring a minimum level of reproductive success. Helpers benefit through an increase in their inclusive fitness in the absence of opportunities for independent breeding (i.e. ecological constraints) and access to breeding vacancies in the natal or adjacent territories (i.e. benefits of philopatry). However, the majority of breeding unit-years comprised unassisted breeders, which suggests that pairs are selectively favoured under certain environmental or demographic conditions.

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Disasters, emergencies, incidents, and major incidents - they all come back to the same thing regardless of what they are called. The common denominator is that there is loss of life, injury to people and animals and damage and destruction of property. The management of such events relies on four phases: 1. Prevention 2. Preparation 3. Response 4. Recovery Each of these phases is managed in a different way and often by different teams. Here, concentration has been given to phases 2 and 3, with particular emphasis on phase 3, Response. The words used to describe such events are often related to legislation. The terminology is detailed later. However, whatever the description, whenever prevention is not possible, or fails, then the need is to respond. Response is always better when the responders are prepared. Training is a major part of response preparation and this book is designed to assist those in the health industry who need to be ready when something happens. One of the training packages for responders is the Major Incident Medical Management and Support (MIMMS) Course and this work was designed to supplement the manual prepared by Hodgetts and Macway-Jones(87) in the UK. Included is what the health services responder, who may be sent to an event in which the main concern is trauma, should know. Concentration is on the initial response and does not deal in any detail with hospital reaction, the public health aspects, or the mental health support that provides psychological help to victims and responders, and which are also essential parts of disaster management. People, in times of disaster, have always been quick to offer assistance. It is now well recognised however, that the 'enthusiastic amateur', whilst being a well meaning volunteer, isn't always what is needed. All too often such people have made things worse and have sometimes ended up as victims themselves. There is a place now for volunteers and there probably always will be. The big difference is that these people must be well informed, well trained and well practiced if they are to be effective. Fortunately such people and organisations do exist. Without the work of the St John Ambulance, the State Emergency Service, the Rural Fire Service the Red Cross and the Volunteer Rescue Association, to mention only a few, our response to disasters would be far less effective. There is a strong history of individuals being available to help the community in times of crisis. Mostly these people were volunteers but there has also always been the need for a core of professional support. In the recent past, professional support mechanisms have been developed from lessons learned, particularly to situations that need a rapid and well organised response. As lessons are learned from an analysis of events, philosophy and methods have changed. Our present system is not perfect and perhaps never will be. The need for an 'all-hazards approach' makes detailed planning very difficult and so there will probably always be criticisms about the way an event was handled. Hindsight is a wonderful thing, provided we learn from it. That means that this text is certainly not the 'last word' and revisions as we learn from experience will be inevitable. Because the author works primarily in New South Wales, many of the explanations and examples are specific to that state. In Australia disaster response is a State, rather than a Commonwealth, responsibility and consequently, and inevitably, there are differences in management between the states and territories within Australia. With the influence of Emergency Management Australia, these differences are being reduced. This means that across state and territory boundaries, assistance is common and interstate teams can be deployed and assimilated into the response rapidly, safely, effectively and with minimum explanation. This text sets out to increase the understanding of what is required, what is in place and how the processes of response are managed. By way of introduction and background, examples are given of those situations that have occurred, or could happen. Man Made Disasters has been divided into two distinct sections. Those which are related to structures or transport and those related directly to people. The first section, Chapter 3, includes: • Transport accidents involving land, rail, sea or air vehicles. • Collapse of buildings for reasons other than earthquakes or storms. • Industrial accidents, including the release of hazardous substances and nuclear events. A second section dealing with the consequences of the direct actions of people is separated as Chapter 4, entitled 'People Disasters'. Included are: • Crowd incidents involving sports and entertainment venues. • Terrorism From Chapter 4 on, the emphasis is on the Response phase and deals with organisation and response techniques in detail. Finally there is a section on terminology and abbreviations. An appendix details a typical disaster pack content. War, the greatest of all man made disasters is not considered in this text.

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Aim: The aim of this thesis is to describe the process by which the inherited disease, cystic fibrosis, (CF) was recognised as an important clinical entity in the United Arab Emirates (UAE) and the Sultanate of Oman (Oman). It examines the clinical presentation of the first patients and assesses their degree of severity. Further, it describes the first studies carried out to determine the underlying CF mutations associated with the disease in the UAE and Oman. An estimate is offered of the birth frequency of the condition. Overall, the cultural, geographical and historical aspect of the societies in which the disease occurs is stressed. Methods: An initial literature search was carried out using Medline of any literature pertaining to the Arab World and CF. this was read and classified into the relevance to Arabs in general, the Middle East and then specifically the Arab (Persian) Gulf societies. Thereafter, a clinic was established at Tawam Hospital, Al Ain, UAE, for children presenting With chronic respiratory disease that could serve as a national referral centre. It was run by the Author as a service of the Paediatric Department of the UAE University Medical School. I sent a letter to every Paediatrician working in the UAE informing them of our clinic and offering our services for the diagnosis and management of chronic respiratory disease in children. This was based on the author's experience as a respiratory paediatrician in Australia and New Zealand and as the Professor of Paediatrics in the UAE. No such service then existed in the UAE. Funding was sought to establish a research programme and develop a molecular genetics laboratory in the UAE Medical School. A series of successful research applications provided the grants to commence the investigations. Once a small number of children had been identified as having CF from those referred to the respiratory clinic, the initial project was to assess and report their clinical presentation. Following this an early start was made on the identification of the mutations responsible. Once these were established an attempt was made to estimate the frequency of the condition at birth. Additional clinical studies revolved around assessing the severity of the condition that was associated with the main mutations that were identified. A clinical comparison was made with those with the mutation AF508 and the other main mutation, despite the obvious limitation of small numbers then available. Radiological assessment was made to evaluate the progression of the disease. The final aspect of the study was to assess patients from Oman and compare their findings and mutations with the neighbouring UAE. Based on information gained hypotheses are proposed regarding the spread of the gene mutation by population drift. Thesis outline: A literature review is presented in the form of a critique on the disease and a resume of the relevant aspects of the genetics of CF. Additionally, facts about the two countries' geography and history are presented. Finally, knowledge about CF mutations and population origins from other areas is presented. The second main section deals with the clinical features of the disorder as it presents in the UAE. Molecular findings are then presented and details of the common mutation found in Bedouin Arabs. Hypotheses are then presented based on the information gathered. Results: CF is not a rare disease in the Arab children of the UAE and Oman. These findings refute previous reports of CF being a rare or non-existent disease in Arabs. The condition presents with a severe clinical picture, with early colonisation of the respiratory tract with staphylococcus, haemophilus and pseudomonas organisms, even with conventional CF management practices in place. The CF mutation S549R is prevalent in Arabs of Bedouin stock, while AF508 is found in those of Baluch origin. The former may be descendants of Arabs who left southern Arabia and travelled to the Trucial Coast at the time of the destruction of the great dam at Marib. The origins of this mutation may lie in the area that corresponds to the modern Republic of Yemen. The latter groups are descendants of those who came originally from Baluchistan. It is hypothesised also that the ancestral home of the AF508 mutation may be in the geographical area now known as Baluchistan, that spans three separate modern political territories. The evidence presented supports the concept that the S549R mutation may be associated with a severe, if not the severest, clinical pattern recognised. It equates with that seen with the homozygous AF508 genotype. The absence of an additional mutation in the promoter region accounts for the different clinical pattern seen in previously described patients. Conclusions: There needs to be a major awareness of the presence of CF as a severe clinical disease in the children of the Gulf States. The clinical presentation and findings support the concept of under recognition of the disease. Climatic conditions put the children at special risk of hyponatraemia and electrolyte imbalance. The absence of surviving adults with the disease suggests premature deaths have occurred, but the high fertility rates have maintained the gene pool for this recessive disorder.

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Linear strips of vegetation set within a less-hospitable matrix are common features of landscapes throughout the world. Depending on location, form and function, these linear landscape elements include hedgerows, fencerows, shelterbelts, roadside or streamside strips and wildlife corridors. In many anthropogenically-modified landscapes, linear strips are important components for conservation because they provide a large proportion of the remaining wooded or shrubby habitat for fauna. They may also function to provide connectivity across the landscape. In some districts, the linear strips form an interconnected network of habitat. The spatial configuration of remnant habitat (size, shape and arrangement) may influence habitat suitability, and hence survival, of many species of plant and animal in modified landscapes. Near Euroa in south-eastern Australia, the clearing and fragmentation of temperate woodlands for agriculture has been extensive and, at present, less than 5% tree cover remains, most of which (83%) occurs as linear strips along roads and streams. The remainder of the woodland occurs as relatively small patches and single isolated trees scattered across the landscape. As an assemblage, arboreal marsupials are woodland dependent and vary in their sensitivity to habitat loss and fragmentation. This thesis focusses on determining the conservation status of arboreal marsupials in the linear network and understanding how they utilise the landscape mosaic. Specifically, the topics examined in this thesis are: (1) the composition of the arboreal marsupial assemblage in linear and non-linear woodland remnants; (2) the status and habitat preferences of species of arboreal marsupial within linear remnants; and (3) the ecology of a population of the Squirrel Glider Petaurus norfolcensis in the linear network, focusing on population dynamics, spatial organisation, and use of den trees. The arboreal marsupial fauna in the linear network was diverse, and comprised seven out of eight species known to occur in the district. The species detected within the strips were P. norfolcensis, the Sugar Glider Petaurus breviceps, Common Brushtail Possum Trichosums vulpecula, Common Ringtail Possum Pseudocheirus peregrinus, Brush-tailed Phascogale Phascogale tapoatafa, Koala Phascolarctos cinereus and Yellow-footed Antechinus Antechinus flavipes. The species not detected was the Feathertail Glider Acrabates pygmaeus. Survey sites in linear remnants (strips of woodland along roads and streams) supported a similar richness and density of arboreal mammals to sites in non-linear remnants (large patches or continuous tracts of woodland nearby). Furthermore, the combined abundance of all species of arboreal marsupials was significantly greater in sites in the linear remnants than in the non-linear remnants. This initial phase of the study provided no evidence that linear woodland remnants support a degraded or impoverished arboreal marsupial fauna in comparison with the nonlinear remnants surveyed. Intensive trapping of arboreal marsupials within a 15 km linear network between February 1997 and June 1998 showed that all species of arboreal marsupial (except A. pygmaeus) were present within the linear strips. Further analyses related trap-based abundance estimates to measures of habitat quality and landscape structure. Width of the linear habitat was significantly positively correlated with the combined abundance of all arboreal marsupials, as well as with the abundance of P. norfolcensis and T. vulpecula. The abundance of T. vulpecula was also significantly positively correlated with variation in overstorey species composition, Acacia density and the number of hollow-bearing trees. The abundance of P. norfolcensis was positively correlated with Acacia density and canopy width, and negatively correlated with distance to the nearest intersection with another linear remnant. No significant variables were identified to explain the abundance of P. tapoatafa, and there were insufficient captures of the remaining species to investigate habitat preferences. Petaurus norfolcensis were resident within the linear network and their density (0.95 -1.54 ha-1) was equal to the maximum densities recorded for this species in continuous forest elsewhere in south-eastern Australia. Rates of reproduction were also similar to those in continuous forest, with births occurring between May and December, a mean natality rate of 1.9, and a mean litter size of 1.7. Sex ratios never differed significantly from parity. Overall, the population dynamics of P. norfolcensis were comparable with published results for the species in contiguous forest, clearly suggesting that the linear remnants currently support a self-sustaining, viable population. Fifty-one P. norfolcensis were fitted with radio transmitters and tracked intermittently between December 1997 and November 1998. Home ranges were small (1.3 - 2.8 ha), narrow (20 - 40 m) and elongated (322 - 839 m). Home ranges were mostly confined to the linear remnants, although 80% of gliders also utilised small clumps of adjacent woodland within farm paddocks for foraging or denning. Home range size was significantly larger at intersections between two or more linear remnants than within straight sections of linear remnants. Intersections appeared to be important sites for social interaction because the overlap of home ranges of members of adjacent social groups was significantly greater at intersections than straight sections. Intersections provided the only opportunity for members of three or more social groups to interact, while still maintaining their territories. The 51 gliders were radiotracked to 143 different hollow-bearing trees on 2081 occasions. On average, gliders used 5.3 den trees during the study (range 1-15), and changed den trees every 4.9 days. The number of den trees used by each glider is likely to be conservative because the cumulative number of den trees continued to increase over the full duration of the study. When gliders shifted between den trees, the mean distance between consecutive den sites was 247 m. Den trees were located throughout a glider's home range, thereby reducing the need to return to a central den site and potentially minimising energy expenditure. Dens were usually located in large trees (mean diameter 88.5 cm) and were selected significantly more often than expected based on their occurrence within the landscape. The overall conclusion of this thesis is that the linear network I studied provides high quality habitat for resident populations of arboreal marsupials. Important factors influencing the suitability of the linear remnants appear to be the high level of network connectivity, the location on soils of high nutrient status, the high density of large trees and an acacia understorey. In highly fragmented landscapes, linear habitats as part of the remaining woodland mosaic have the potential to be an integral component in the conservation of woodland-dependent fauna. The habitat value of linear strips of vegetation should not be underestimated.

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The vast majority of bird species build a nest in which to breed. Some species build more than one nest, but the function of most multiple nest-building remains unclear. Here we describe the unusual nest-building behaviour of the Australian Reed Warbler Acrocephalus australis, and test experimentally the hypotheses that multiple nest-building is related to individual condition or territory quality, and plays a role in mate assessment. Australian Reed Warblers built two types of nest structures: 'type I' nests, which were used for eggs and nestlings, and 'type II' nests, which were structurally distinct from type I nests, did not support eggs, nestlings or adults and were not essential for successful breeding. The number of type II nests built in each territory varied. Type II nests were only built before breeding had commenced in a territory and females were not observed participating in their construction, supporting a role in female mate choice. Birds provided with supplementary food built significantly more type II nests than control birds. However, supplementary-fed birds did not have greater pairing success, and the addition of further type II nests to territories did not increase the pairing rate or type II nest construction in those territories. There was no relationship between the presence of type II nests and either reproductive success or likelihood of nest predation. We discuss the implications of these results in light of previous suggestions regarding the function of multiple nest-building in birds.

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Little grassbirds (Megalurus gramineus) are small, sexually monomorphic passerines that live in reed beds, lignum swamps and salt marshes in southern Australia. The breeding biology and patterns of sex allocation of the little grassbird were investigated over a single breeding season. Our observations of this species in the Edithvale Wetland Reserve revealed a highly male-biased population sex ratio, with some breeding territories containing several additional males. Nevertheless, there was little compelling evidence that little grassbirds breed cooperatively. The growth rates of male and female nestlings were similar and, as predicted by theory, there was no overall primary sex ratio bias. However, the primary sex ratio was female-biased early in the breeding season and became increasingly male-biased later in the breeding season.

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The Australian endemic brown songlark, Cinclorhamphus cruralis, is one of the most sexually size-dimorphic of all birds, and yet its breeding ecology remains poorly documented. Here we redress this situation by describing the breeding activities of brown songlarks over three years (1998–2000) in the semi-arid grasslands of south-western New South Wales. Study populations of this nomadic species were selected in late August of each year on the basis of high adult abundance. Adult males at these sites were, on average, 2.3 times heavier than females. Over the three seasons, nesting activities started in early to late August and continued until early November or December. Males were highly polygynous and, on average, occupied territories of about 4.0 ha. Nests were well concealed at the base of small shrubs and grass tussocks or in thick herbage. Clutches ranged in size from 2 to 5 eggs (mean 3.2) and were incubated exclusively by the female for 11–13 days (mean 12.1). Nestlings received a range of invertebrate prey, mainly from the female, for 10–14 days (mean 11.5) before leaving the nest. Only 17% of nesting attempts were estimated to be successful, and each of these nests produced an average of 2.7 fledglings. Predators, including foxes, Vulpes vulpes, and brown snakes, Pseudonaja textilis, were the main cause of nest failure. Some females produced replacement clutches following nest failure, while others laid second clutches after the success of an earlier brood. We speculate that extreme size dimorphism has evolved in this species because (i) males compete physically for breeding territories, and (ii) habitat heterogeneity and excellent visibility of their surroundings allow some males to defend territories of sufficient size to support nesting by multiple females

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Objective: To investigate the extent and cost of travel undertaken by women accessing Victorian termination of pregnancy services.

Design, setting and participants: This was a multi-centre, cross-sectional observational study of women receiving privately funded pregnancy termination services, conducted between November 2002 and June 2003 at eight major pregnancy termination service providers in Victoria.

Main outcome measures: Distance travelled, money and time expended undertaking travel, and reasons women chose particular clinics.

Results: Of the 1,244 Australian resident respondents who resided in Victoria, 9.3% travelled more than 100 km to access services. Teenagers were 2.5 times more likely than other respondents to travel further than 100 kilometres (km) (18.2% compared with 7.8%, OR=2.5, 95% CI 1.5-4.2, p<0.001). Women originated from all Australian States and Territories except South Australia and 13.7% were from Statistical Divisions other than Melbourne. More than one-third of respondents (41.3%) chose their clinic because they were referred by a doctor or general practitioner.

Conclusion: Many pregnancy termination patients face substantial and immediate costs beyond the service fee, as well as the diffculties associated with poor continuity of care and signifcant time away from home. Patients and service providers should be consulted further to determine appropriate clinical services, support services and subsidy schemes for the sizeable proportion of patients who undertake long-distance travel to access pregnancy termination services.

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Australians are eating far more salt than is good for health. In May 2007, the Australian Division of World Action on Salt and Health (AWASH) launched a campaign to reduce population salt intake. A consumer survey was commissioned to quantify baseline aspects of awareness and behaviour related to salt and health amongst Australians. A total of 1084 individuals aged 14 years or over were surveyed by ACA Research using an established consumer panel. Participants were selected to include people of each sex, within different age bands, from major metropolitan and other areas of all Australian states and territories. Participants were invited via email to complete a brief questionnaire online. Two-thirds knew that salt was bad for health but only 14% knew the recommended maximum daily intake. Seventy percent correctly identified that most dietary salt comes from processed foods but only a quarter regularly checked food labels for salt content. Even fewer reported their food purchases were influenced by the salt level indicated (21%). The survey showed a moderate understanding of how salt effects health but there was little evidence of action to reduce salt intake. Consumer education will be one part of the effort necessary to reduce salt intake in Australia and will require government investment in a targeted campaign to achieve improvements in knowledge and behaviours.