Today I highlight a new paper just out online in Diversity and Distributions by James Watson and colleagues: Wilderness and future conservation priorities in Australia. It’s certainly one for the Potential list.
Australia has a pretty bad biodiversity conservation track record – we have some of the worst mammal extinction trends in the world, and we’ve lost at least 50 % of our forested area since European colonisation. Despite our relatively large system of parks and reserves, things aren’t going to well (even in the parks!).
Our rapidly expanding influence means that we have to start protecting larger and larger areas if we want to have any chance of slowing the modern extinction crisis. This means we have to go beyond dedicated biodiversity reserves and sequester more ‘wilderness’ (defined as “…large areas that have experienced minimal habitat loss“). Watson and colleagues therefore used Australia as a good example to determine the extent to which the national protected area network captures ‘wilderness’, and how Australia’s planned expansion of the reserve system will include ‘wilderness’ in the future.
Although there wasn’t much planning involved initially, Australia (like many other countries) started to take biodiversity conservation seriously in the mid-1990s, such that now we have about 11 % of our 7.7 million km2 land area within a National Reserve System. Planning didn’t feature heavily in the early years, but it has been embraced now by nearly all planning bodies within government.
Using estimates of the total wilderness area in Australia (Fig. a), Watson and colleagues determined how much was included in the Reserve System (Fig. b), and how this value changed between 2000 and 2006.
Of the 2.93 million km2 of wilderness (38 % of land area, mostly in northern and western Australia), only 14 % was protected in 2000. This value increased marginally to 19 % by 2006 as the size of the Reserve System itself increased by 37 % (i.e., from 652597 to 895326 km2).
Bottom line – our growth in reserve area didn’t really capture the necessary wilderness; instead, gains were made in areas largely modified by humans. Even where wilderness has been captured, it’s predominately in ‘multiple use’ regions (incorporating mining, forestry and grazing, for example).
This isn’t a bad thing really – by focussing on areas of high biodiversity value that are under relatively high threat embraces the biodiversity hotspot approach to conservation and emphasises restoration. This is, of course, needed. But not incorporating a wider component of the habitats within wilderness could bias conservation toward range-restricted species.
Watson and colleagues therefore make a number of recommendations:
- We should strive to quantify and map spatially the important ecological and evolutionary processes that drive the distribution and abundance of biodiversity so they can be explicitly incorporated into reserve area prioritisations.
- We should focus on predicting the magnitude and distribution of future threats and incorporate them into the spatial prioritisation framework.
- We should incorporate realistic constraints (e.g., financial costs) into prioritisation.
- We need to map and analyse a range of social and economic factors that define opportunities for conservation in conjunction with information on conservation values, threats and costs.
The bottom line is that we need to find a better balance between planning that protects threatened species and ecosystems in already highly fragmented (threatened) landscapes, and planning that protects large areas of wilderness that still contains most of its conservation values (wilderness). We’re getting there, but slowly, and hopefully in time to save our remaining threatened species from extinction.
Watson, J., Fuller, R., Watson, A., Mackey, B., Wilson, K., Grantham, H., Turner, M., Klein, C., Carwardine, J., Joseph, L., & Possingham, H. (2009). Wilderness and future conservation priorities in Australia Diversity and Distributions DOI: 10.1111/j.1472-4642.2009.00601.x