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Addressing threats to biodiversity from pest species is a global challenge. One such challenge is to mitigate the impact of an overabundant Australian songbird, the noisy miner Manorina melanocephala, on woodland birds. The overabundance of noisy miners is listed as a key threatening process under federal biodiversity legislation, but current understanding of where and how noisy miner populations can be managed to yield conservation benefits is unclear. We evaluated the effectiveness of noisy miner removal across 12 treatment areas totaling 3913 ha and nine control areas totaling 1487 ha important for the critically endangered regent honeyeater Anthochaera phrygia. Removal of noisy miners significantly reduced their densities in all but one of the treatment areas. In 10 of the 12 treatment areas, noisy miner densities remained below an impact threshold of 0.65–0.83 birds ha−1 for at least 3 to more than 12 months. The percentage of suitable noisy miner habitat in the surrounding landscape was not a strong predictor of noisy miner management success. Regent honeyeaters occupied six treatment areas, nesting successfully in four. The abundance of other songbirds increased post‐miner removal in seven areas, decreased in three, and was mixed in two. Data from the control areas showed some variation in songbird numbers was independent of noisy miner management. We conclude that noisy miners can be managed in areas of high conservation value for a minimum cost of AUD $10 ha−1. Larger treatment areas may be more important than the broader landscape context in maintaining long‐term noisy miner suppression. Standardized, long‐term monitoring is crucial to identify not only the drivers of pest species recolonization but also locations where threats from pests on endangered species can be addressed effectively while minimizing animal welfare and financial costs. [ABSTRACT FROM AUTHOR]

Act 1 - prequel: From the first European settlement to the formation of the Australian Entomological Society, much of Australian entomology was driven by the need to understand and manage a raft of indigenous and invasive pest insect species. This very applied imperative influenced how people approached ecology, which tended to be very much autecological: species focused questions addressing the distribution and abundance of the organism. Not surprisingly that applied focus continued after the formation of the society in 1964, which marks the beginning of Act 2 - The last 50 years. Here I focus in part on what has been published in the flagship journal of the society since its inception and analyse the trends that are evident. The emphasis on basic biology is reflected in the publication trends in the society's journal. I use some of the key native and imported pests - locusts, H elicoverpa, Queensland fruit flies, sugar cane-feeding scarabs, diamondback moth - to illustrate how ecological thinking has developed. There were some Australian giants in the field of population ecology, and their public disagreements continue to reverberate. But there have been many notable contributions by lesser mortals, if only students and their mentors would read and cite appropriately! One can only allude to the encore, or Act 3 - the sequel or the next 25-50 years. The thinking of Australian entomologists continues to be at the forefront of spatial ecology, perhaps reflecting the scale at which fieldwork is undertaken in Australia. Other younger members of the society will no doubt write the epitaph and obituaries of the current crop of researchers and judge their contributions accordingly. [ABSTRACT FROM AUTHOR]

Wide community participation in ecological restoration projects is encouraged because of the multiple values generated. However, it is often assumed that volunteer projects cannot contribute to the production of generalizable ecological knowledge because they are locally focused and don't follow scientific protocols or ecological theory. Anecdotally, the many successful volunteer projects suggest that some amateurs possess insight that could benefit restoration ecology generally, but the processes of generating, testing, and sharing local restoration knowledge remains poorly understood. This ethnographic study of the volunteer restorationist organization, Friends of Organ Pipes National Park, in Victoria, Australia, explores local ecological knowledge generation. Our results suggest that there are similarities between amateurs' knowledge practices and traditional ecological knowledge such as extended apprenticeships, narratives, and the importance of experience of place. There are also similarities with practices of science, for example, semistructured planning, monitoring, evaluating, and documenting observations. We conclude that the ways amateurs generate, share, and test knowledge are complex and dynamic, producing a kind of hybrid between local and scientific knowledge. [ABSTRACT FROM AUTHOR]

Almost all researchers now accept that Australia's Aborigines were managing their country with the broad-scale use of fire when Europeans arrived. In respect to Tasmania, this article goes further, arguing that fire was not merely broad-scale, but applied variably and precisely, to make, then connect, a complex range of useful ecosystems. The article also argues that Aboriginal land management must be seen in cultural as well as ecological terms. [ABSTRACT FROM AUTHOR]

The article presents a study investigating the effect of independent measures of both spatial pattern and heterogeneity of elements on bird occurrence in farm-scale agricultural mosaics in southeastern Australia. The study uses information-theoretic approach to identify the mosaic properties that influenced bird species richness. Results fo the study shows that woodland birds were richer in mosaics with higher cover of native vegetation while open-tolerant species responded to the extent of scattered trees. It was observed that mosaic heterogeneity and landscape context had the most influence in bird species richness.

To a large extent, the condition of riparian areas in Australia is determined by the management actions of private landholders. In this study, we discuss findings from our research in the Goulburn Broken Catchment comparing landholder and scientist assessments of the condition of riparian areas. We interviewed 33 landholders and undertook ecological condition assessments at 38 sites on privately managed river frontages. Using mail survey data that included landholder assessments of riparian condition, we were then able to compare landholder and scientist assessments. Despite substantial effort in this catchment to improve riparian condition, the riparian zones sampled were generally in poor condition. Landholder and scientist assessments of ecological condition showed a significant positive correlation. This indicated broad agreement, despite some substantial differences in assessment of some components of the condition score. Disparities between scientist and landholder assessments were related to the estimation of native ground cover, leaf litter cover and tree canopy continuity within riparian zones. The capacity of this simple assessment tool to differentiate varying levels of riparian zone degradation demonstrates the potential utility of mailed, self-assessment surveys to inform management programs and decisions about the allocation of resources for restoration efforts. [ABSTRACT FROM AUTHOR]

1. Ecological invasions are often associated with persistent changes to underlying ecological processes. Restoration of invaded communities is dependent on manipulation of these processes to favour the target species composition and impart resistance to further invasion. We applied these principles to extensively degraded grassy woodlands in temperate agricultural regions of Australia, where widespread invasion by mediterranean annuals is related to altered ecological processes such as soil nutrient cycling. 2. We investigated carbon supplementation and spring burns, in association with re-establishment of native perennial grasses, as potential management tools for manipulating nitrogen cycling, soil seed banks and establishment conditions in degraded woodland understoreys. Through these mechanisms we aimed to enhance native cover and increase resistance to invasion by exotic annuals. 3. In two contrasting degraded remnants, repeated sucrose applications temporarily reduced soil nitrate to inferred pre-European levels, which dramatically reduced growth of exotic annuals and enhanced native perennial abundance. Repeated spring burns did not reduce soil nitrate but reduced exotic annual grasses through effects on soil seed banks and/or establishment conditions. 4. Spring burns and carbon supplements both significantly enhanced establishment of Themeda australis, a dominant tussock grass prior to European settlement. Combinations of T. australis seed addition and either spring burning or carbon supplements enhanced native plant abundance more effectively than treatments without seed addition. 5. Within 18 months of their establishment, T. australis seedlings significantly reduced soil nitrate in some treatments, providing a preliminary indication that re-establishment of a dense sward of this species may restore ecosystem function to a low-nitrate state that favours native perennials over exotic annuals. 6. Synthesis and applications. Ecological restoration can be viewed as targeted intervention in species–environment interactions, whereby ecological conditions are manipulated to enhance establishment or vigour of key species, and these species in turn help restore ecological processes that favour the target species composition. In grassy ecosystems re-establishing a perennial sward of appropriate native tussock grasses may be critical for restoring pre-disturbance nitrogen cycles and improving resistance to invasion by exotic annuals. Carbon supplements and spring burns facilitate this process through complementary mechanisms. [ABSTRACT FROM AUTHOR]

1. Evaluation of the success of biological control agents is essential to improve the efficiency and safety of future programmes. This study assessed the impact of Carmenta mimosa, a stem-mining moth, introduced into northern Australia as a biological control agent of mimosa Mimosa pigra. Litter fall, seed banks, vegetation cover, density and age structure of mimosa stands were compared using data collected at nine sites where Carmenta mimosa was present and eight sites where it was initially absent. 2. Mimosa seed rain was negatively correlated with Carmenta mimosa damage and declined by more than 90% at the highest Carmenta mimosa densities. Seed banks also declined with Carmenta mimosa damage. 3. Percentage cover of competing vegetation was significantly higher under stands defoliated by Carmenta mimosa and this inhibited mimosa seedling establishment and apparently increased the susceptibility of mimosa to fire, by increasing fuel loads beneath stands. 4. Four of the eight stands where Carmenta mimosa was absent expanded and none contracted. In contrast, none of the nine stands where Carmenta mimosa was present expanded and three contracted. Analysis of the age structure of mimosa stands indicated that contracting stands were typified by an absence of seedling regeneration. 5. In contrast to previous studies, no impact could be attributed to the flower feeder Coelocephalapion pigrae or to the stem-mining moth Neurostrota gunniella, whilst the bruchid Acanthoscelides puniceus consumed up to only c. 10% of seed. However, it is argued that, while these agents are unlikely to suppress dense mimosa thickets, they may reduce the rate mimosa can expand. 6. Synthesis and applications. By preventing stand regeneration, Carmenta mimosa is predicted to cause widespread reductions in mimosa populations and should therefore be redistributed to areas of mimosa where it is absent. Differences between the age structures of stands with Carmenta mimosa present may highlight how biological control could succeed for a suite of woody legume weeds with long-lived seed banks. [ABSTRACT FROM AUTHOR]

1. The movement of native herbivores onto agricultural land is a key management issue world-wide as they may compete with domestic livestock for pasture and contribute to overgrazing and soil erosion. Eastern grey kangaroosMacropus giganteusare viewed as a problem species in temperate south-eastern Australia, where high-density populations in reserves encroach on nearby farmland.2. This study examined home range size and use inM. giganteusacross different types of land use and in relation to population density and pasture availability.3. Farmland adjacent to either radiata pine plantations or reserves supporting high-density populations ofM. giganteuswas subject to frequent incursions by kangaroos moving onto farmland to rest or graze. However, animals from reserves moved on average only 135 m onto farms.4. Home ranges ofM. giganteuswere significantly smaller in the reserves than in farm study sites where population densities were lower. At reserve sites, home range size was limited by higher population densities and limited opportunity for dispersal across surrounding open farmland because of a lack of cover. Home range size was not affected by resource availability.5. Where suitable vegetation cover occurred on farmland (e.g. woodland remnants or scrub),M. giganteusoccurred as resident or roving small mobs. This may be seen by farmers as a disincentive to preserve remnant vegetation as it can provide habitat for unwanted native wildlife.6. Home range attributes ofM. giganteussuggest the species could be controlled by culling. However, recolonization occurs quickly and little is known of dispersal.7. Synthesisandapplications.Population density, presence of cover and reluctance to disperse across cleared landscapes are key factors influencing kangaroo home range size and use of adjacent farmland. Currently, little incentive exists for farmers to preserve remnant vegetation, as it may be regarded as providing habitat for unwanted or‘pest’ kangaroos. Given the potential importance of remnant vegetation on private land for the conservation of plants and other species of wildlife, government incentives and compensation programmes may be required to limit land clearing on farms and to encourage improved pasture management.Journal of Applied Ecology(2005)42, 99 –107doi: 10.1111/j.1365-2664.2005.01001.x [ABSTRACT FROM AUTHOR]

1. Timber harvesting exemplifies many aspects of experimental manipulation in applied ecology. Evaluation of the research approaches used to assess ecological effects of harvesting thus has relevance to a diverse range of ecological questions that address large-scale and human impacts on the environment. 2. We measured the frequency of approaches, and also design and statistical issues, in assessments of harvesting effects on three response variables (tree regeneration, vertebrates and water) in two major native forests of south-east Australia. Our evaluation was based on 124 documents that contain unique, field-based research and that represent the complete written record (published and unpublished) of relevant research prior to mid-2002. 3. The dominant approach was contrasts between manipulated stands, nearly always involving mature and old-growth stands as the reference or control. In studies of tree regeneration, focus on wood-production objectives was apparent in the relatively frequent use of stocking standards, and in the use of between- and within-stand contrasts without a control condition. Comparatively greater use of models in vertebrate and water studies suggested more frequent integration of generic principles and, in water studies, reflected strong collective knowledge based on the repeated use of BACI-type designs (i.e. before–after, control–impact) or long-term data sets. 4. Statistical issues such as poor reporting of experimental designs and of sample statistics were common. Explicit hypotheses were rare, and there was no evidence of definition of critical effect sizes, use of power analysis or use of non-classical statistical approaches (e.g. Bayesian inference). 5. Lack of treatment replication was widespread in between-stand contrasts and less frequent in within-stand contrasts. Inappropriate interpretation of results from non-replicated experimental designs remains an ongoing issue. 6. Synthesis and applications. The amount of information obtainable from stand-level manipulations of forest would substantially increase through greater attention to data quality and experimental protocols. Studies require broader experimental contexts, including their potential place in meta-replication frameworks. Increasingly, constraints of large-scale manipulations necessitate the integration of data and the acknowledgement of uncertainty in formalized systems (e.g. Bayesian methods and adaptive management frameworks). Our evaluation suggests the alternative is a perpetuation of short-term, isolated studies that repeat errors and have limited potential to refine knowledge on the ecological effects of timber harvesting and other similarly scaled disturbances. Journal of Applied Ecology (2004) 41, 585 –598 [ABSTRACT FROM AUTHOR]

Abstract Fire is a significant feature of Australia's savannas. Its use is being encouraged for cattle rangeland management, but there is little knowledge of the ecological effects of prescribed fire regimes on native biodiversity. The responses of ant communities to five experimental fire regimes over 2 years are reported from the Victoria River District in the semi-arid tropics of northern Australia. The experiment was stratified at two levels: soil type (red and black) and fire treatment (unburnt; burnt twice in successive years in early (May) or late (October) dry season and unburnt thereafter; and burnt twice, 3 years apart, in early or late dry season). Ants were sampled twice in April, corresponding with the end of the 1997 and 1998 wet seasons. Ant species richness was not responsive to fire treatment, but reduced with time since fire on black soil. Total ant abundance also reduced with time since fire on the black soil, with significant different abundances in burnt versus unburnt plots in the 1998 sample. Soil type and sampling time had the greatest influence on ant community composition in multivariate analysis than did fire regime, although there were moderate gradients of time since fire with the black soil plots. The abundance of 19 species were significantly different between fire regimes in anova, 13 on red soil and six on black soil. The abundance of eight species (four each on red and black soil) changed significantly with time since fire, with seven promoted by burning. Ant functional group profiles changed little with fire. Total ant abundance and richness had significant relationships with key pasture species and vegetative variables. The responses of ants largely recapitulated those of plants, birds and reptiles on the same plots. It is envisaged that ants will have an important role to play in the sustainable management of Australia's rangelands aiding the off-reserve conservation of biodiversity. [ABSTRACT FROM AUTHOR]

Environmental questions have become a permanent feature of the political landscape in contemporary Australia and now play a significant role in election campaigns at both state and federal levels. Indeed, one of the most significant policy debates in the 1996 Federal election focussed on the environmental policy proposed by the Liberal/National Party coalition, which sought to fund a host of environmental programs from the proceeds of a part privatisation of Telstra. The trade-offs involved in this policy have generated substantial opposition to it and served to underline the prominence of environmental questions in Australian politics. Despite the importance of 'the environment' in popular thought, public debate is still typically characterised by 'feel good' policy announcements by politicians, sensationalist media reporting and deceptive claims by some environmental interest groups. Whilst progress has undoubtedly been made, the result has often been a plethora of inchoate and frequently conflicting policies. Not surprisingly this 'muddle through' approach has produced numerous instances of government intervention not only failing to meet its planned objectives but also generating unintended consequences. [ABSTRACT FROM AUTHOR]

Invasive species have had a profound impact on ecosystems all over the world. Their presence can lead to fundamental changes in the biodiversity of a given ecosystem as well as the extinction of native species. In particular, this work looks at the effect on the Gecarcoidea natalis (Red Crab) population on Christmas Island due to the presence of vast arrays of supercolonies containing Anoplolepis gracilipes (Yellow Crazy Ant). We primarily study the inter-species interaction occurring during the crab migration to the island coast. We propose a microscopic model for the dynamics of the crabs and ants with the goal of increasing crab survival. Through analysis of the model, we investigate a range of potential preventative measures that could be taken to preserve the native crab population dependent on their locations. The main result of this work is that by considering the locations of ant supercolonies incorporated into Monte Carlo simulations of the model, we can identify the order that the supercolonies need to be removed to provide the greatest chance at survival for the crabs per migration cycle., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Inc. All rights reserved.)

The article reports that the Minister for Planning of Victoria, Australia, has instructed the Major Projects Victoria to prepare an Environment Effects Statement for the planned Long-term Containment Facility for prescribed industrial waste under the authority of the Environment Effects Act of 1978. The proposed facility is aimed at containing treated prescribed industrial waste for which there are no foreseen capabilities for re-use. The facility will feature containment bays and capping system.

The article presents the key accomplishments of Australia's Green Power program as contained in the Green Power Quarterly Report covering the period January 1, 2006 to March 31, 2006. More than 240,000 residential and 13,000 industrial customers have joined the program. The program's customers increased by 20% over the fourth quarter of 2005, while sales increased by 32% over the first quarter of 2005. The program registered a 65% and 35% overall sales for the commercial and residential sectors, respectively. There were 20 Greenpower products offered by 12 providers for the quarter.

The article reports that the Brian Robinson Foundation Fellowship for 2006 has been awarded to Larissa Brown during the Environment Industry Dinner on June 5, 2006, Victoria, Australia, for her project in identifying leadership skills and effective methods of teaching said skills to bright young Victorians working on environmental sustainability. As part of her task, Brown will be visiting and auditing international environmental leadership programs. The government of Victoria established the Foundation in 2004 in cooperation with the Environment Protection Authority and EcoRecycle Victoria.