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Animal welfare legislation is placing increasing emphasis on researchers to demonstrate competence in all procedures that their research may require, even if some are infrequently performed. Many field biologists rarely need to carry out euthanasia, but they may nevertheless require a legal, transportable and reliable method to be available for them so that they can obtain the necessary approvals to undertake their work. A small CO2 system, reproducing the recommended method used widely in laboratories, seemed likely to meet these requirements. Three sources of CO2 that could be taken into field situations were tested: soft drink carbonating machines; the chemical production of CO2 by mixing sodium bicarbonate and acetic acid; and, small disposable CO2 cartridges. Of these, a system designed to use CO2 cartridges was found to be the most reliable and practical. This new equipment was tested for efficiency against a conventional, standard laboratory CO2 euthanasia system using laboratory mice (8) and rats (6) that were due for euthanasia. No statistical difference was found between the two systems in the time taken for either species to succumb to CO2. This new equipment therefore meets welfare guidelines and its small size, compact nature and simplicity to operate make it highly suited to use in the field. Finally, because cartridges are available in a variety of sizes, it can be readily adapted and scaled to meet the needs of different taxa. [ABSTRACT FROM AUTHOR]

River red gum ( Eucalyptus camaldulensis ) is the most widely-distributed eucalypt, an important timber resource, and critical to the sustainable function of many Australian waterways. Agricultural development, including decades of river regulation, has resulted in extensive degradation of E. camaldulensis woodlands, and restoration is now required to maintain ecological function in many floodplain areas. To aid restoration planning, we quantified the structural characteristics of E. camaldulensis trees in an intensively farmed region of eastern Australia. We studied tree populations on two rivers with different hydrological regimes: (1) Bogan River - ephemeral and surrounded by dryland agriculture, and (2) Macquarie River - permanent and the focus of irrigated agriculture. The two populations showed clear differences in allometric relationships. Trees on the ephemeral river were shorter with relatively wider canopies than trees with similar stem diameter on the permanent river. Trees on the ephemeral river progressed through stages of senescence at smaller stem sizes than those on the permanent river. Tree growth was episodic and strongly related to tree senescence, but the amount of growth in stem diameter was less on the ephemeral river. Tree senescence and stem diameter had the strongest effects on the probability of trees bearing hollows, with a lesser interactive effect of river hydrology. Variation among individual trees, sites and sub-catchments was large and not fully explained by the site characteristics measured. Our data enable predictions of future vegetation growth and fauna habitat development in semi-arid riparian woodlands that are not managed for silvicultural production. Our findings indicate that differences in the hydrological regimes of inland rivers manifest as differences in structural attributes of E. camaldulensis , even among individuals occupying the same catchment management area. Such differences should be reflected in future management strategies to sustain the function and biodiversity of riparian forests and woodlands. [ABSTRACT FROM AUTHOR]

Nest boxes have been widely used across the world to provide shelter for animal species, often to restore areas following the loss of natural tree hollows. While the microclimates of installed nest boxes have been studied, limited attention has been paid to whether microclimate is influenced by nest box size, shape and entrance dimensions. In this study the temperature and humidity patterns were recorded within six nest box designs that were exposed to direct sunshine. All were constructed of 19 mm plywood but varied in length by a factor of 2X, in volume by 3.5X and in entrance areas by 5X. All next boxes behaved the same thermally, closely following ambient during the night, but during the day they heated to 5 °C warmer than ambient by mid-afternoon. Fluctuations in humidity varied, with small nest boxes with large entrances being closer to ambient humidity than those with small entrances or large volumes. Overall, nest box size and shape had no detectable influence on the internal temperature fluctuations, but did to a slight extent on humidity patterns. Construction material and nest box placement are the likely drivers of the temperature and humidity patterns within nest boxes, and need to be the focus of efforts to keep nest boxes habitable when deployed, and designs should be selected on the basis of the target animal's preferences for size and shape. [ABSTRACT FROM AUTHOR]

Essential to effective vegetation management and habitat conservation is an understanding of tree and stand structure. However, such data for Australian Eucalyptus woodlands come mostly from forestry research and tend to be restricted to production forest types, and merchantable stems and species. We aimed to improve understanding of allometric relationships and stand dynamics for temperate Eucalyptus from critically endangered temperate woodlands. We explored relationships among tree height, diameter at breast height (DBH), crown width, crown senescence, and vegetation density. We measured 3748 naturally-occurring trees on 105 one-hectare sites in remnant vegetation in an agricultural landscape in semi-arid eastern Australia. Four species accounted for 94% of trees measured: Eucalyptus camaldulensis Dehnh. (river red gum), E . melliodora A.Cunn. ex Schauer (yellow box), E . microcarpa Maiden (grey box) and E. populnea F.Muell. subsp. bimbil L.A.S.Johnson & K.D.Hill (poplar box). Six Eucalyptus species were present in relatively low numbers. At about 15 cm DBH, growth changed from being directed primarily at height gain to increasing relative crown width. Trees with DBH ⩾ 15 cm showed large and increasing variation in shape with increasing DBH, and tree dimensions varied among species. For a given DBH, yellow box were taller with relatively narrow crowns than poplar box, and river red gum and grey box intermediate to these two species. Human manipulation of the agricultural landscapes has impacted on these allometric relationships. Past attempts by people to kill trees has resulted in frequent coppicing, with up to 13 trunks. Up to 50% of trees of each species (mean 29%) had multiple stems and multi-stemmed trees had relatively broader crowns than single-stemmed trees. Similarly, decreasing vegetation density by tree removal generally resulted in shorter trees with wider canopies for any DBH. Progression through crown development and senescence was similar among species except that it occurred at different trunk sizes for different species. The variability of allometric relationships within temperate Eucalyptus species, combined with their variable growth rates, makes it difficult to accurately predict outcomes of current land management decisions in terms of vegetation structure and biological habitat attributes. [ABSTRACT FROM AUTHOR]

Conservation planning for many fauna relies on an ability to predict length of time lags to production of habitat requirements in restoration plantings or with natural regeneration. One key consideration is the growth rate of dominant trees, as tree age and size are linked to characteristics that provide fauna habitat, such as canopy cover, tree hollows and coarse woody debris. In this study we examined growth rate and mortality of Eucalyptus species for all individuals with diameter at breast height (DBH) ⩾ 15 cm on forty one-ha sites in temperate semi-arid woodland in eastern Australia. Over five years (2008–2013) encompassing drought and flood, mean growth was <2.5 cm in DBH. Mixed effects models indicated that growth rate differed among species, and decreased with increasing senescence and greater initial foliage projective cover on the site. There was no link between initial tree DBH and growth rate for most species. Growth in DBH was similarly variable in large and small trees. Consequently increases in cross-sectional area, and hence biomass accumulation, are likely to be faster in larger trees. Growth of E. microcarpa , E. camaldulensis , E. blakelyi and E. conica did not significantly differ but was faster than that of E. populnea and E. melliodora . The random factors site and tree identity (for multi-stemmed trees) explained around 10% and 30% of the overall variability in growth rate respectively. Twelve trees (∼1%) died and 4 live trees were cut down and removed. Five (6.5%) of the 75 standing dead trees present in 2008 collapsed, and a further eight (10.5%) were cut down and removed by people. Forty saplings of four species with DBH < 15 cm in 2008 grew to DBH ⩾ 15 cm by 2013, equating to a recruitment rate of <4%, but this occurred on only nine of the 40 sites. Our study suggests mortality rate is being met by recruitment rate at the regional scale, but recruitment was extremely patchy and may result in site scale extinctions. The growth rates measured indicate that trees planted to create fauna habitat may take centuries to reach sizes that would contain large nesting or roosting hollows for fauna. [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]