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Context: Fauna nestboxes are used for conservation, research and mitigation against tree hollow/cavity loss. Scant attention has been given to the microclimate inside boxes until recently, with concern that nestboxes may be ineffective or a thermal trap because of high internal temperatures during summer. Aim: Our study used construction design principles to guide modifications to nestboxes to reduce maximum temperatures inside boxes. Methods: Five trials were undertaken, and modifications included addition of thermal mass, creation of a double wall system and painting the box and/or outer wall white. Nestboxes were placed in full sun. Key results: The internal temperature difference from ambient between the worst (unpainted box) and the best box design was around 7°C at 30°C, and 9.5°C at 40°C. Painting boxes white had a marked impact on internal temperatures, but the single modification giving most protection from heat gain was construction of a ventilated double wall. This created a shaded air space around the internal box. Painting the outer layer white further improved insulation, and painting both the box and outer layer gave the best result. Conclusion: Double-walled, pale nestboxes can provide significant protection from solar heat. Implications Adding an air space to insulate a nestbox has considerable advantages over alternatives − it contributes little weight (compare using denser wood/materials); avoids environmental issues associated with insulators such as polystyrene or foil batts; is inexpensive; is easy to retrofit a second layer around existing boxes and it should improve nestbox longevity as the outer layer protects the inner box from weathering. Nestboxes may be a thermal trap in hot exposed conditions making them ineffective mitigation or conservation tools. Trials quantified that double-walled, pale painted boxes are substantially cooler than single walled nestboxes. Creating a double-walled air space avoids polluting synthetic insulation, is light-weight and can be retrofitted to existing boxes. [ABSTRACT FROM AUTHOR]

To purchase or authenticate to the full-text of this article, please visit this link: http://dx.doi.org/10.1111/j.1745-5871.2007.00474.x Byline: MICHAEL BEDWARD (1), CHRISTOPHER C. SIMPSON (1), MURRAY V. ELLIS (1), LISA M. METCALFE (1) Keywords: sheep-wheat belt; vegetation clearing history; logistic regression; spatial contagion Abstract: Abstract We consider the history of woodland clearing in central western New South Wales, Australia, which has led to the present highly cleared and fragmented landscape. A combined approach is used examining available historical land-use data and using regression analysis to relate the pattern of cleared and wooded areas in the recent landscape to environmental variables, taking into account the contagious nature of clearing. We also ask whether it would be possible to apply a simple simulation modelling approach to reconstruct a credible historical sequence of clearing in the study area. The historical data indicate that annual clearing rates have varied substantially in the study area and selective tree removal (ringbarking and thinning) has been common. These findings make it unlikely that a simple simulation approach would replicate the spatial and temporal sequence of woodland loss. Our regression results show that clearing patterns can be related to environmental variables, particularly annual rainfall and estimated pre-European vegetation type, but that patterns are dominated by contagion. Author Affiliation: (1)Biodiversity Conservation Science Section, Department of Environment and Conservation, PO Box 1967, Hurstville, New South Wales, Australia. Article History: Received 12 February 2007; Revised 8 May 2007; Accepted 31 May 2007 Article note: (*) Corresponding author. Email: michael.bedward@environment.nsw.gov.au

We used clearly defined measures of weather and time of day to determine their impacts on the number of bird species recorded in 5439 area-search surveys of 142 one-hectare sites in open temperate woodlands. Surveys recording the highest number of species spanned the full range of times of day and weather conditions. For our full dataset, the number of species recorded dropped by 16% at higher wind speeds (>20 km/h), 0.8%/h after sunrise (or 7.4% in the afternoon compared to morning), and 0.5% per degree temperature increase, but was unrelated to cloud cover. Resampling our full dataset, we separated impacts of effort from weather and analysed scenarios which might arise with time or budget constraints. Dawn surveys were less affected by time and weather, and recorded more species than other scenarios per unit of effort, especially at species-rich sites. We demonstrate that setting thresholds for these variables is not warranted if this reduces sample size in a study. Conversely, if researchers are restricted to a fixed number of surveys, then our data highlight that thresholds may be used to optimise results by avoiding periods when less productive conditions, particularly winds >20 km/h, prevail. [ABSTRACT FROM AUTHOR]

Summary: River Red Gums (Eucalyptus camaldulensis Dehnh.) are large trees that dominated many of continental Australia's riparian areas, providing abundant hollows for nesting and denning fauna. Land clearing and forestry have reduced the availability of large trees, and much of the remaining forest is dominated by small regrowth trees that lack visible hollow entrances. Inspection of recently felled River Red Gums revealed that heartwood decay, a precursor of hollow formation, can be common in relatively small trees. Internal decay and voids remain inaccessible until stochastic damage exposes them, which may not occur until the tree is old, and hence probably large. This discrepancy indicates that there is likely to be a size range of trees into which artificial entrances can be added to quickly increase hollow availability in landscapes undergoing active restoration as fauna habitat. [ABSTRACT FROM AUTHOR]

The article focuses on widespread historic declines of woodland-dependent species in southern Australia, including many bird species, and presents a study aimed to report changes over time to the avifauna in woodland in the Macquarie-Bogan sub-region of central New South Wales (NSW) and to investigate its relationships with landscape and climatic conditions. It also states that the restoration of these woodland bird communities active habitat reconstruction and management.

Loss and fragmentation of the native vegetation of the Central Western Plains of New South Wales was followed by declines of woodland-dependent species. Drought is likely to have further suppressed many animal populations. Here we report on changes in woodland bird reporting rates between surveys in 2005-2009 (drought declared period) and surveys in 2010-2013 following the droughtbreaking rains of 2010. By 2013 the number of species detected per survey had just recovered to the level of surveys in 2005/6.The 2013 species composition of the region was similar to that recorded in the 2005-2009 drought surveys, with half of the small insectivorous and nectarivorous woodland birds remaining rare and restricted. Woodland remnants in the landscape continued to be dominated by the same, usually large, species of birds, but reporting rates of 13 of the 15 most common species declined. Conversely, several smaller, foliage gleaning passerines had higher reporting rates post-drought, with Striated Pardalote and Western Gerygone becoming two of the most frequently recorded species. Taxonomic and life history attributes usually did not predict population changes for species postdrought, with the only feeding guild showing a consistent trend being the mistletoe specialists, with only two species. Even after the drought-breaking rains of 2010, there appears to be a reduced vigour in these woodland landscapes. [ABSTRACT FROM AUTHOR]

We conducted acoustic surveys of insectivorous bat fauna in riparian areas along the Macquarie and Bogan River systems in the wheatbelt of semi-arid central-western New South Wales, Australia. In surveys of 10 sites we detected I I species and two species groups of bats in eight genera. Four species, Chocolate Wattled Bat Chalinolobus morio, Large-footed Myotis A1yot/s macropus, Large Forest Bat Vespadelus darlingtoni and Southern Forest Bat V. regulus, are predominantly Bassian (chiefly coastal) in their recorded distributions but were detected in the semi-arid Eyrean sub-region on two rivers in vegetation dominated by River Red Gum Eucalyptus camaldulensis. The findings of this study highlight the need for further research to assess the importance of riparian corridors as habitat for insectivorous bats in semi-arid New South Wales. [ABSTRACT FROM AUTHOR]

The woodlands of southern Australia have been extensively cleared for agriculture. The loss and fragmentation of the native vegetation has been followed by dramatic declines in woodland-dependant species. Here we present data from the Central Western Plains of New South Wales on the occurrence of birds in woodlands that have been highly fragmented and structurally altered over the last 150 years. The species composition of the region is still very similar to that recorded 3 decades earlier but many small insectivorous and nectivorous woodland birds are rare and restricted, while the woodland patches and remnant tree groves in the landscape are now dominated by the Galah, Noisy Miner, Australian Magpie, Crested Pigeon, Apostlebird, Magpie-lark, Grey-crowned Babbler, Australian Raven, Eastern Rosella and Pied Butcherbird. [ABSTRACT FROM AUTHOR]