140 research outputs found
Bird responses to targeted revegetation : 40 years of habitat enhancement at Clarkesdale Bird sanctuary, central-western Victoria
A program of planting Australian shrubs and trees has been conducted in degraded farmland at the Clarkesdale Bird Sanctuary (central-western Victoria) since the 1960s, to address the issue of declining native birds, as perceived by the late landowner Gordon Clarke. The shrubs and trees were selected to attract birds, and included many species that were not native to the region. This form of management is often practised by private landholders (at various scales), but its effects are rarely documented. Bird surveys were conducted for this study between 1999 and 2001 at 27 sites: 11 in native eucalypt forest on ridges and slopes, 13 in planted areas on ridges and slopes, and three in planted areas on river-flats and a small gully (with three supplementary sites in a pine plantation). Total bird abundance and species per count were highest in the planted sites on river-flats and gully, and higher in the planted sites on ridges and slopes than in native forest on similar topography. Honeyeaters (Meliphagidae), Superb Fairy-wrens Malurus cyaneus, open-country birds, seed-eating birds and five insectivorous guilds reached their maximum abundance in planted sites. Barkforaging insectivores, canopy-foraging insectivores, frugivores and a generalist insectivore were marginally more common in native forest than in planted sites. Introduced birds were uncommon. Generalised linear modelling showed that total bird abundance was positively related to the cover of planted native vegetation, native low shrubs and young wattles Acacia spp. and to the presence of indigenous Cherry Ballart Exocarpos cupressiformis. Various guilds showed positive relationships with the cover of planted native vegetation, native low shrubs, young wattles, original old wattles, original old eucalypts and trees with small or large hollows. The planting program has provided new habitat for many native forest birds. A greater challenge is to address the needs of some uncommon species that have declined locally, such as the Brown Treecreeper Climacteris picumnus and Speckled Warbler Chthonicola sagittata
Modeling abundance using N-mixture models: the importance of considering ecological mechanisms
Predicting abundance across a species' distribution is useful for studies of ecology and biodiversity management. Modeling of survey data in relation to environmental variables can be a powerful method for extrapolating abundances across a species' distribution and, consequently, calculating total abundances and ultimately trends. Research in this area has demonstrated that models of abundance are often unstable and produce spurious estimates, and until recently our ability to remove detection error limited the development of accurate models. The N-mixture model accounts for detection and abundance simultaneously and has been a significant advance in abundance modeling. Case studies that have tested these new models have demonstrated success for some species, but doubt remains over the appropriateness of standard N-mixture models for many species. Here we develop the N-mixture model to accommodate zero-inflated data, a common occurrence in ecology, by employing zero-inflated count models. To our knowledge, this is the first application of this method to modeling count data. We use four variants of the N-mixture model (Poisson, zero-inflated Poisson, negative binomial, and zero-inflated negative binomial) to model abundance, occupancy (zero-inflated models only) and detection probability of six birds in South Australia. We assess models by their statistical fit and the ecological realism of the parameter estimates. Specifically, we assess the statistical fit with AIC and assess the ecological realism by comparing the parameter estimates with expected values derived from literature, ecological theory, and expert opinion. We demonstrate that, despite being frequently ranked the “best model” according to AIC, the negative binomial variants of the N-mixture often produce ecologically unrealistic parameter estimates. The zero-inflated Poisson variant is preferable to the negative binomial variants of the N-mixture, as it models an ecological mechanism rather than a statistical phenomenon and generates reasonable parameter estimates. Our results emphasize the need to include ecological reasoning when choosing appropriate models and highlight the dangers of modeling statistical properties of the data. We demonstrate that, to obtain ecologically realistic estimates of abundance, occupancy and detection probability, it is essential to understand the sources of variation in the data and then use this information to choose appropriate error distributions. Copyright ESA. All rights reserved
Redrawing Boundaries: WITNESS and the Politics of Citizen Videos
This article engages with several pressing issues revolving around ‘citizen witnessing’, with specific reference to the human rights advocacy group, WITNESS. In the course of tracing WITNESS’ development over the past two decades, it offers an evaluative assessment of the challenges its members have faced in promoting a grassroots, citizen-centred approach to video reportage. More specifically, this advocacy is informed by an ethical commitment to advancing human rights causes by equipping citizens in crisis situations with cameras, and the training to use them, so that they might bear witness to the plight of others. In so doing, this article argues, WITNESS offers a tactical reformulation of the guiding tenets of peace journalism, one with considerable potential for recasting anew its strategic priorities
Using smart pumps to help deliver universal access to safe and affordable drinking water
It is estimated that broken water pumps impact 62 million people in sub-Saharan Africa. Over the last 20 years, broken handpumps have represented US$1·2–1·5 billion of lost investment in this region, with 30–40% of rural water systems failing prematurely. While the contributory factors are complex and multi-faceted, the authors consider that improved post-construction monitoring strategies for remote water projects, which rely on smart pumps to monitor operational performance in place of physical site visits, may address some of these problems and help reduce the heavy time and resource demands on stakeholders associated with traditional monitoring strategies. As such, smart pumps could play a significant role in improving project monitoring and might subsequently help deliver universal access to safe and affordable drinking water by 2030, which constitutes one of the key targets of United Nations sustainable development goal 6 and is embedded in some national constitutions
Outside the gate: sub-urban legal practices in early medieval England
Many aspects of English early medieval (Anglo-Saxon) legal landscapes can be discerned in archaeological and toponymic evidence, ranging from the locations of legislative councils and judicial assemblies to sites of capital punishment. Among the corpus of such sites a striking group can be detected at the periphery of urban spaces. Gates into a number of towns appear to have functioned as legislative meeting-places, and even gave their names to some legally constituted communities, while suburban locations also feature prominently as sites of gallows and public punishment. In this paper historical, archaeological and toponymic evidence is used to examine this phenomenon of suburban legal practices and to pose questions about the wider dimensions of the early medieval legal landscape
Rethinking journalism practice through innovative approaches to post conflict reporting
Journalism has a long history of interviewing vulnerable people caught up in natural disasters, conflict or tragedy. While it is widely recognised that journalists have an important role to play in telling the stories of those traumatised by such events, the concepts of ‘peace journalism’ or ‘journalism of attachment’ have often elicited a negative reaction in traditional journalistic circles. Drawing on the authors’ research project working with young people embroiled in Colombia’s civil conflict, this paper sets out an alternative and innovative approach to the retelling of the stories of others. It outlines how the research team engaged with the young people, some of whom had operated as child soldiers before Colombia’s peace accord with FARC rebels, and encouraged them to narrate their own stories in their own style. Through a series of workshops, the team experimented with oral and visual representations of their experiences, staying close to their accounts, enabling their voices to be heard. The participants combined traditional narrative with animation to produce a short documentary setting out their hopes for peace and reconciliation. This project, with its focus on immersion and listening, offers an alternative approach for journalists trying to relay the experiences of traumatised individuals marginalised in society as a result of their participation in the armed conflict. While the project was located in the specific context of Colombia, the paper argues that the journalistic approaches used could be applied more widely to the reporting of trauma in post conflict or marginalised communities
Forest landscape ecology and global change: an introduction
Forest landscape ecology examines broad-scale patterns and processes and their interactions in forested systems and informs the management of these ecosystems. Beyond being among the richest and the most complex terrestrial systems, forest landscapes serve society by providing an array of products and services
and, if managed properly, can do so sustainably. In this chapter, we provide an overview of the field of forest landscape ecology, including major historical and present topics of research, approaches, scales, and applications, particularly those concerning edges, fragmentation, connectivity, disturbance, and biodiversity. In addition, we discuss causes of change in forest landscapes, particularly land-use and management changes, and the expected structural and functional consequences that may result from these drivers. This chapter is intended to set the context and provide an overview for the remainder of the book and poses a broad set of questions related to forest landscape ecology and global change that need answers
Variation at the DRD4 locus is associated with wariness and local site selection in urban black swans
Managing Habitat Trees in Queensland Forests: A Report by the Habitat Tree Technical Advisory Group to the Queensland Department of Natural Resources, Forest Resources
Bird population responses to wildfire and planned burns in foothill forests of Victoria, Australia
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