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Forest vertebrate fauna provide critical services, such as pollination and seed dispersal, which underpin functional and resilient ecosystems. In turn, many of these fauna are dependent on the flowering phenology of the plant species of such ecosystems. The impact of changes in climate, including climate extremes, on the interaction between these fauna and flora has not been identified or elucidated, yet influences on flowering phenology are already evident. These changes are well documented in the mid to high latitudes. However, there is emerging evidence that the flowering phenology, nectar/pollen production, and fruit production of long-lived trees in tropical and subtropical forests are also being impacted by changes in the frequency and severity of climate extremes. Here, we examine the implications of these changes for vertebrate fauna dependent on these resources. We review the literature to establish evidence for links between climate extremes and flowering phenology, elucidating the nature of relationships between different vertebrate taxa and flowering regimes. We combine this information with climate change projections to postulate about the likely impacts on nectar, pollen and fruit resource availability and the consequences for dependent vertebrate fauna. The most recent climate projections show that the frequency and intensity of climate extremes will increase during the 21st century. These changes are likely to significantly alter mass flowering and fruiting events in the tropics and subtropics, which are frequently cued by climate extremes, such as intensive rainfall events or rapid temperature shifts. We find that in these systems the abundance and duration of resource availability for vertebrate fauna is likely to fluctuate, and the time intervals between episodes of high resource availability to increase. The combined impact of these changes has the potential to result in cascading effects on ecosystems through changes in pollinator and seed dispersal ecology, and demands a focused research effort., (© 2015 John Wiley & Sons Ltd.)

Land clearing threatens biodiversity, impairs the functioning of terrestrial, freshwater, and marine ecosystems, and is a key contributor to human-induced climate change. The rates of land clearing in the State of Queensland, Australia, are at globally significant levels, and have been the subject of intense and polarised political debate. In 2016, a legislative bill that aimed to restore stronger controls over land clearing failed to pass in the Queensland Parliament, despite the clear scientific basis for policy reform. Here, we provide a short history of the recent policy debate over land clearing in Queensland, in the context of its global and national ecological significance. Land clearing affects regional climates, leading to hotter, drier climates that will impact on the Queensland economy and local communities. Loss of habitat from land clearing is a key threatening process for many endangered animals and plants. Runoff from land clearing results in sediment and nutrient enrichment, which threatens the health of the Great Barrier Reef. Australia has made national and international commitments to conserve biodiversity and reduce our greenhouse gas emissions, but current land clearing policies are not consistent with these commitments. Stronger regulation is needed to reduce vegetation loss, such as target-based regulation, which sets a cap on land clearing and could effectively halt vegetation loss over the long term. Lasting policy reform is required, and we recommend an effective policy mix that restricts clearing, provides economic opportunities for vegetation retention, and informs the Australian community about the value of native vegetation. [ABSTRACT FROM AUTHOR]

Aim Climate change is predicted to adversely affect wildlife populations at the trailing edge of their range, with extreme weather events acting as a catalyst for local extinctions and range contractions. We assessed the relative importance of long-term climate averages, short-term drought and habitat in predicting species occupancy and range edge, using the koala ( Phascolarctos cinereus) as a case study. Location Queensland, Australia. Methods We used mixed effects models to quantify the influence of habitat quality and climate on koala distribution at the trailing edge of their range, at three spatial scales. We used piecewise logistic regression to estimate thresholds in the relationship between the range edge and key environmental variables. Results Both climatic and habitat variables explained koala presence. At the site scale, the quality of habitat was important within landscapes that had experienced higher levels of rainfall during a decade-long drought. The spatial pattern of the koala's present-day western range limit reflects closely a breakpoint of ~350 mm in summer rainfall during the drought years, supporting both theoretical predictions and empirical research on the influence of climate extremes on contracting edge populations. Main conclusions The distribution of fauna at their range margin in semi-arid regions reflects extreme climate events, such as drought. Within suitable climate conditions, habitat quality is important in determining site occupancy. The identification and protection of habitat refugia, where local microclimates and habitat characteristics can mitigate the impacts of extreme events on fauna species at the contracting edge of the range, may allow species to persist for longer under changing climate conditions. [ABSTRACT FROM AUTHOR]

Environmental changes result in physiological responses of organisms, which can adversely affect population dynamics and reduce resistance to disease. These changes are expressed in chronic levels of stress. The measurement of glucocorticoid (GC) concentrations in faeces is a non-invasive method for monitoring stress in wildlife. The metabolism and excretion of steroids differ significantly between species and, as a consequence, non-invasive methods must be physiologically validated for each species. Koalas (Phascolarctos cinereus) are declining in numbers through much of their range. The role of chronic stress in koala populations has not been identified. Prior to the assessment of faecal GC concentrations in wild koala populations, the excretion timing and concentrations of GCs need to be determined. In this study, we assessed a method for identifying and measuring the concentrations of GC metabolites in faecal pellets of captive koalas following ACTH treatment. The results show that an elevation of plasma cortisol concentrations, using sustained release of ACTH, results in elevated concentrations of faecal cortisol/cortisol metabolites. Taking into account the excretion time lag, an increase in faecal cortisol metabolite concentrations corresponds to the release of GCs from the adrenal cortex as early as 36 h before faecal pellet collection. The calculations of steroid partitioning of plasma cortisol showed that the ACTH-stimulated values were significantly different from the control values for the concentrations of free, corticosteroid-binding globulin-bound and albumin-bound cortisol. This study validates the use of faecal cortisol analysis to assess the activity of the hypothalamo-pituitary-adrenocortical axis in freshly collected koala faecal pellets and indicates that the method should be suitable to assess the adrenocortical status of koalas in wild populations. [ABSTRACT FROM AUTHOR]

Abstract: Globally, land use and land cover changes to provide resources for human society have led to loss of biodiversity and declines in ecosystem services. Climate change will compound these impacts. Ecological restoration can reverse environmental degradation and is starting to restore ecological services, as well as help mitigate climate change. Although this may be an anathema to some, we must systematically assess and proactively redesign and manage the landscapes we inhabit so they can continue to provide ecosystem services essential for all species, including humans. We define three restoration pathways based largely on existing land use and the degree of modification: restoration for areas of natural ecosystems; repair for production landscapes; and reinvention for urban areas. Challenges and research priorities include understanding: the effects of mean climate change and climate extremes on species’ distribution and ecosystem composition; how restoration can be used for carbon sequestration; the effects of proximate and endogenous drivers on landscape change; how to better bio-design landscapes for multiple functions; integration of different scales of restoration planning and design; and the establishment of long-term monitoring and adaptive management. [Copyright &y& Elsevier]

Highlights: [•] Higher faecal cortisol levels were recorded during drought compared to post-flood. [•] Drought diets were mainly composed of species with high leaf moisture. [•] Low minimum temperatures increased faecal cortisol concentrations. [ABSTRACT FROM AUTHOR]