At a glance
It seems unlikely, given the current overall poor status and deteriorating trends in biodiversity and the high impact of increasing pressures, that overall biodiversity outcomes will improve in the short or medium term. Our current investments in biodiversity management are not keeping pace with the scale and magnitude of current pressures, and we are increasingly needing to adapt to a potential reduction or shift in the ecosystem services we rely on. It is anticipated that novel ecosystems with a mixture of native and exotic species will increase as the distribution and abundance of invasive species continue mostly unabated. Biodiversity and broader conservation management will require major reinvestments across long timeframes to reverse deteriorating trends.
The Australian national outlook 2015 has indicated that it is possible to achieve a balance of sustainable environments, and economic and human population growth, but significant changes in policy, and implementation of new technology and tools will be required. For example, it is evident that market-based instruments for sustainable land management and protection of biodiversity will be increasingly important.
The co-development and application of effective research and management models with Indigenous people is key to improving management of areas that are vital for the ongoing maintenance of important elements of Australia’s biodiversity. Such approaches have huge potential to improve our ability to respond to both existing and possible new impacts through participatory monitoring and impact assessment methods, leading to new ways of managing biodiversity that enable sustainable development across a wide range of tenures.
The current overall state and trend of biodiversity has not improved since 2011, and present a very mixed outlook, with many assessments showing poor status and worsening trends. In addition, the impact of many of the pressures on biodiversity is high and increasing. Current management actions and effectiveness appear insufficient to redress the declining status of biodiversity. Although the impact of pressures overall has increased, the resources available for managing biodiversity, research and monitoring have not. An increase in the area of land managed for conservation provides some increased protection for biodiversity; however, the majority of our threatened species and communities are under-represented in the conservation estate.
Australian governments and NRM bodies that manage biodiversity are now considering the adoption of environmental accounting that includes trend and condition reporting for environmental assets, to better evaluate the status of our natural capital and better assess the return on investment in the environment. A whole-of-landscape approach is required to effectively manage impacts and achieve meaningful outcomes. More and more biodiversity management in any location involves a co-investment of multiple partners, and therefore reporting needs to move to measurements that report on the outcome of the total investment.
The concept of managing for resilience is becoming more widely adopted to manage landscapes in a changing environment, so that resilient, functioning systems can provide ecosystem services and can withstand, or recover from, external pressures while maintaining ecological functions. The pressure on biodiversity from cumulative pressures, including climate extremes, is increasing, and presents a serious and ongoing threat to the viability of many ecosystems. Outputs from the AdaptNRM project suggest that the potential degree of ecological change expected under high-emissions scenarios is very high in some parts of Australia (Williams K et al. 2014). For instance, across most of Australia, only about half of the current plant species are rated as having the potential to persist in their current locations by 2050. The highest potential for change is projected for the western coastline of south-western Australia, including the coastal sand-plain region where Perth is located. In contrast, areas such as Tasmania, the Nullarbor Plain and parts of central Australia show the lowest potential for change, although some degree of change is still expected.
During the past 5 years, concerns have increased that some present-day environments may disappear or become severely restricted in Australia in the future. Although most widespread ecological communities are considered unlikely to disappear completely, there are predictions that some communities will disappear at local levels. Plants and amphibians appear to be most at risk from the potential disappearance of their environments. Novel ecological environments (new ecological communities that currently do not exist) may arise in the future; however, very few areas are expected to become completely novel under current climate change scenarios.
Across Australia, species are on the move, with changes in range that have not previously been recorded (see Box BIO23). This presents both new opportunities for conservation and new dilemmas on what to conserve and how to deal with ‘newcomers’. Whether it be unwanted crocodiles moving south, or a greater variety of fish species caught by anglers, the need to manage emerging novel ecosystems will put increased pressure on our existing systems for biodiversity management.
Box BIO23 Range expansion of flying foxes
Range expansion may occur when:
- existing habitat that has not previously been colonised is reached
- appropriate conditions develop outside a species’ distribution, and the species colonises this new habitat
- appropriate habitat develops within a species’ range but in areas that were previously not occupied, and the species colonises this habitat.
More controversially, changes in the distribution of a species’ abundance (e.g. where the abundance of a species changes in different parts of its distribution in response to changes in conditions) might also be included here. In many instances, such changes in the distribution of a species’ abundance is the precursor to another form of range expansion.
Australian flying foxes (Pteropodidae, Pteropus spp.) are highly mobile species that exhibit all these forms of range expansion. Range expansions have occurred in several species. From the late 1800s to 2007, the black flying fox (P. alecto) expanded its southern range boundary polewards by 123 kilometres per decade, on average (Roberts et al. 2012). More recently, in the south of its range, the vulnerable grey-headed flying fox (P. poliocephalus) has established a permanently occupied breeding camp in Adelaide, some 500 kilometres from the nearest camp. In the north, newly established and permanently occupied breeding camps at Finch Hatton and Ingham are roughly 500 and 900 kilometres, respectively, outside the range boundaries. In each case, the camp is separated from the existing range, but is largely in an appropriate habitat.
Apparent expansion into adjacent but previously unoccupied habitat has been seen in the grey-headed flying fox, with apparently new camps established outside the species’ range on the Western Plains and in previously unoccupied habitat within the species range (e.g. Canberra and Tumut) during the past decade. However, examination of historical records indicates that the species was present in these areas (e.g. Wellington, Goulburn) in the 1800s, suggesting that range boundaries are highly dynamic across long timeframes as conditions vary.
Roberts BJ, Catterall CP, Eby P & Kanowski J (2012). Latitudinal range shifts in Australian flying-foxes: a re-evaluation. Austral Ecology 37(1):12–22.
The greatest perceived threat to biodiversity is the interaction of climate change with the impact of other current pressures. For instance, the projections of changing climate in landscapes with additional pressure from clearing lead to a much more severe outlook for the intensively used agricultural zones of southern and eastern Australia, including parts of Tasmania (Williams K et al. 2014).
The pressures on biodiversity from invasive weeds and animals are increasing. Overall, the negative impacts outweigh our current management efforts, and the outlook for the future is not positive. At least 2700 plant species introduced from other countries have already established self-sustaining populations in Australia, and the rate of establishment of further species is estimated at about 12 per year (Scott et al. 2014). Additionally, approximately 26,000 other exotic species, mainly garden plants, have also been introduced into Australia, and it is likely that many new weeds are yet to emerge from this group. With such a large threat already in Australia, and global trade representing an increased risk for further introductions, weed management will increase in importance in the future. Under climate change, we should anticipate the pressure from invasive species to further increase as the suite of invasive species changes and some species become more invasive (Scott et al. 2014).
Although the outlook presented here is grim, highlighting the multiple stresses biodiversity faces in Australia, there are multiple avenues for addressing many of these challenges that help to protect the environment, as well as maintaining economic prosperity. The Australian national outlook 2015 (CSIRO 2015) found that, across a range of future scenarios, Australia has the capacity to pursue economic growth and improved living standards while also protecting or improving the natural environment, if this is done with the right choices and technologies. For instance, new land-sector markets for carbon sequestration, energy feed stocks and voluntary conservation could be nationally transformative. Paying landholders for ‘carbon farming’ (sequestering carbon from the atmosphere by restoring vegetation on cleared land) is beginning to assist in controlling erosion, addressing dryland salinity and restoring native habitat. Land-sector credits will be instrumental in reducing Australia’s greenhouse gas emissions, and carbon incentives could also be harnessed to restore significant areas of native habitat, reducing extinction risk by 10 per cent or more (CSIRO 2015, Hatfield-Dodds et al. 2015). This could lead to a transformation, where the problem of changed fire regimes across many parts of northern Australia could become an opportunity for landowners and land managers to take advantage of market-based incentives, and deliver improved fire and environmental management outcomes (Russell-Smith 2016).
Citizen science continues to grow in Australia and has already demonstrated that it is now a key part of the management response required to halt the decline in biodiversity. The Reef Life Survey program (see Box MAR5 in the Marine environment report) provides a network of volunteer citizen scientists who collect species-level data for all conspicuous taxa on a cross-section of Australia’s shallow rocky and coral reefs. The survey program conducted the first Australian continental-scale reef biodiversity assessment based on detailed quantitative data, as one way to monitor biodiversity trends in relation to the key pressures on the marine environment. Similarly, citizen-based birdwatching initiatives provide the most comprehensive species-level bird data available for Australia. These largely voluntary efforts significantly add to existing government and industry-led scientific programs. The overall efficacy of citizen-science efforts is difficult to quantify, because evaluations of the monitoring of data quality and data collation are often not undertaken, and it is not possible to truly gauge their importance in the overall national effort.
Innovative new tools for harvesting biodiversity observations across all environments in Australia are continuing to be developed and taken up by Australians at rates that were unprecedented 5 years ago. Combining traditional approaches with novel ways to monitor and report on the status of species and ecosystems may lead to a revolution in how we perceive the current status of Australia’s biodiversity, and lead to new ways to deal with current declines in biodiversity.
Dr Ian Cresswell
Dr Helen Murphy
