1000 resultados para nest location


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Aim. We characterized changes in reporting rates and abundances of bird species over a period of severe rainfall deficiency and increasing average temperatures. We also measured flowering in eucalypts, which support large numbers of nectarivores characteristic of the region.

Location.  A 30,000-km2 region of northern Victoria, Australia, consisting of limited amounts of remnant native woodlands embedded in largely agricultural landscapes.

Methods. There were three sets of monitoring studies, pitched at regional  (survey programmes in 1995–97, 2004–05 and 2006–08), landscape (2002–03 and 2006–07) and site (1997–2008 continuously) scales. Bird survey techniques used a standard 2-ha, 20-min count method. We used Bayesian analyses of reporting rates to document statistically changes in the avifauna through time at each spatial scale.

Results. Bird populations in the largest remnants of native vegetation (up to 40,000 ha), some of which have been declared as national parks in the past decade, experienced similar declines to those in heavily cleared andscapes. All categories of birds (guilds based on foraging substrate, diet, nest site; relative mobility; geographical distributions) were affected similarly. We detected virtually no bird breeding in the latest survey periods. Eucalypt flowering has declined significantly over the past 12 years of drought.

Main conclusions. Declines in the largest woodland remnants commensurate with those in cleared landscapes suggest that reserve systems may not be relied upon to sustain species under climate change. We attribute population declines to low breeding success due to reduced food. Resilience of bird populations in this woodland system might be increased by active management to enhance habitat quality in existing vegetation and restoration of woodland in the more fertile parts of landscapes.

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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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Most statistical procedures regarding the mean or median may only give valid results when particular conditions about the shape of the data are met. An alternative test is presented in this thesis that does not require certain data shapes but can perform as well or better than the existing tests.

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This thesis, using a computer simulation, studies the effect of the normal distribution assumption on the power of several many-sample location and scale test procedures. It also suggests an almost robust parametric test, namely numerical likelihood ratio test (NLRT) for non-normal situations. The NLRT is found better than all of the tests considered. Some real life data sets were used as examples.

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The thesis covers a series of two and three-dimensional installations created in the investigation of both metaphorical and literal perceptions of form. The journey leads from the idea of painted-related dissolution of form in the early works, to the translation from three-dimensional to two-dimensional installations, and lastly, to experimentation with sound works where non-physical form is explored.

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The rapid recall of influenza virus-specific CD8+ T cell effector function is protective, although our understanding of T cell memory remains incomplete. Recent debate has focused particularly on the CD62L lymph node homing receptor. The present analysis shows that although functional memory can be established from both CD62Lhi and CD62Llo CD8+ T cell subsets soon after initial encounter between naive precursors and antigen, the optimal precursors are CD8+CD44hiCD25lo immune lymphocytes isolated from draining lymph nodes on day 3.5 after influenza virus infection. Analysis of primed T cells at different times after challenge indicates that the capacity to transfer memory is diminished at the peak of the primary cytotoxic T lymphocyte response, challenging speculations that the transition to memory first requires full differentiation to effector status. It seems that location rather than CD62Lhi/lo phenotype may be the more profitable focus for further dissection of the early establishment of T cell memory.

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This study explored families’ views and experiences of their residential location in relation to their children's health. Thematic analysis of interviews with mothers revealed that decisions to live in an outer Melbourne municipality were strongly influenced by ideals around children however; all spoke of experiencing difficulties in raising children in terms of accessing services, recreation facilities, transport and work. Analysis of these findings using Bronfenbrenner's Social Ecology Model revealed how factors could interact to affect children's health and wellbeing. The study findings highlight the importance of parental perceptions of residential location in understanding the relationship between children's health and place.

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Sensor Networks have applications in diverse fields. They can be deployed for habitat modeling, temperature monitoring and industrial sensing. They also find applications in battlefield awareness and emergency (first) response situations. While unique addressing is not a requirement of many data collecting applications of wireless sensor networks, it is vital for the success of applications such as emergency response. Data that cannot be associated with a specific node becomes useless in such situations. In this work we propose a novel dynamic addressing mechanism for wireless sensor networks that are not location-aware. The scheme enables successful reuse of addresses in event-driven wireless sensor networks introducing minimal latencies and efficiently addressing packet loss. It also eliminates the need for network-wide Duplicate Address Detection (DAD) to ensure uniqueness of network level addresses.

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Whether one writes in the field of literary studies or that of creative writing, one begins with the 'blank page'. The field of interest I am calling the 'blank page' has implications for the discipline of creative writing, and can be useful to theorising creativity, writing practice, and pedagogy. One creates out of, or into, the 'blank page '; one's practice is partly determined by how one theorises, however subconsciously, this blank page (how does one start? how blank is the page? how have others figured the blank page); and one teaches students who have to face literal blank pages. ln this paper I will consider how the theorisation of the blank page in literary studies addresses such creative-writing issues. I will then engage D.W. Winnicott's psychoanalytic theory on 'the location of play' to consider the implications of conceptualising the blank page as 'the location of writing'. A Winnicottian approach to the blank page, as a space akin to the potential space of play, allows various insights into the process of writing, especially as a proccss involving paradox.

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In this article, we report on a cross-disciplinary, cross-cultural digital exchange project between Australian Drama and Education students and Dutch English Language and Culture students, and examine the impact of the place-independent, technology-mediated communications and collaboration on their learning trajectories. The intensive, intercultural collaboration between the two groups of students resulted in a 50-minute group-devised, digital theatre play entitled Quarter Acre Dreaming. This play, performed through live interactive media by both Dutch and Australian students, traced the historical development of the Australian suburb, while integrating scenes of Dutch immigration into Australia. In the creative process, the students on either side of the globe interacted through Computer-Mediated Communication (CMC), and used videoconferencing and Skype for live rehearsals and discussions to advance their learning of English, their performance repertoire and cross-cultural understanding.

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Background: A major question in behavioural ecology concerns the relationship between genetic mating systems and the strength of sexual selection. In this study, we investigated the genetic mating system of the two-spotted goby (Gobiusculus flavescens), a useful fish model for the study of sexual selection whose genetic mating system remains uncharacterized. We developed four polymorphic microsatellite markers and used them to conduct parentage analyses on 21 nests collected during the breeding season to examine the rates of multiple mating by males and to test for evidence of alternative mating strategies.

Results: Results of this study indicate that male G. flavescens mate with multiple females and enjoy confidence of paternity. We detected only one instance of sneaking, so cuckoldry contributed a very small percentage (~0.1%) of the total fertilizations in this population. Nests were nearly full and males that maintain larger nests have higher mating and reproductive success, irrespective of body size.

Conclusion: Overall, our investigation shows that G. flavescens is similar to other, related gobies in that the nests of care-giving males often contain eggs from multiple females. However, G. flavescens differs from other gobies in displaying an extremely low rate of cuckoldry. The study of ecological factors responsible for this important