Australasian Science: Australia's authority on science since 1938

Beyond Threat Maps

By Vivitskaia Tulloch and Ayesha Tulloch

Targeting threats alone won’t save our wildlife.

Too often, governments and conservation organisations have only one goal for restoring the populations of declining species: to reduce what they perceive as the main “threat”. However, the focus on ‘“threat hotspots” by nations and international conservation bodies can be wasteful and may even push threatened species closer to the brink.

To manage threats, organisations develop and use “threat maps”. Often these are maps of human pressures affecting species (e.g. loss of forest cover due to land clearing for agriculture and urbanisation, or the location of fishing pressure in marine areas). A huge number of organisations, including The Nature Conservancy, The World Wildlife Fund and the Wildlife Conservation Society, have a long history of developing and using threat maps to direct limited conservation funding. These organisations typically use threat maps to do one of two things: either target the areas that are the furthest removed from the threats for protecting wildlife (pristine “wilderness” areas) or target the areas that have the highest perceived threats to wildlife and work on that threat.

Unfortunately, these kinds of traditional threat-focused approaches have a number of drawbacks. They limit conservationists to solving only one part of the problem, can be expensive compared with alternative management choices, and may have undesired outcomes if the threat being targeted is only one of a suite of problems affecting the wildlife in an area.

For example, consider Australia’s numerous government-funded programs to eradicate introduced foxes in order to protect small native marsupials. If we only target the foxes with poison baiting, the number of feral cats and rabbits, which are suppressed by foxes, tend to boom once the foxes are gone. In many places the small marsupials will still be hunted – only by cats instead – and the rabbits will wreak havoc in the landscape, depriving native animals of food and shelter. Continued investment in fox baiting will do little to restore these populations without new thinking about alternative actions. And this could have serious consequences for conservation.

We recently led an effort to develop a new framework for making efficient and effective conservation decisions that solve these problems. Our main issue is that reducing threats isn’t a biodiversity outcome on its own. Prioritising threats rather than solutions leads us to cling to a single goal – and miss the big picture.

To avoid putting all our resources into “threat hotspots”, we propose a new conservation decision-making framework that considers all the threats, what else lives in the area, whether the threat is stoppable, the costs of alternative conservation actions and how likely they are to succeed.

Through this structured decision-making process we can weigh up the pros and cons of each action, and pick the action that’s not only cost-effective, but also results in positive outcomes for threatened wildlife.

Returning to our fox example, the new framework helps determine the best ways to achieve conservation outcomes that boost long-term survival of small marsupials rather than simply decreasing the number of foxes. This gives us many more options besides killing foxes. For instance, it may be cheaper to restore habitat to provide shelter that protects marsupials directly from multiple predators, or it might be more effective to set up enclosures or guard dogs to protect the breeding locations of threatened animals – and not waste money on baiting foxes at all.

Using this framework helps us pick our battles and know what we can and cannot stop. In doing so, we might find that it’s better to give up on one action when a threat is too difficult or costly to eliminate, and spend the money on something or somewhere else that will have a better outcome for threatened wildlife.

We need new approaches such as these to help save wildlife by ensuring that actions are prioritised in locations where the best outcomes for biodiversity can be achieved, not just in the places that we can map the threat.

Vivitskaia Tulloch and Ayesha Tulloch are members of the ARC Centre of Excellence for Environmental Decisions (CEED). Viv is based at the University of Queensland and Ayesha is based at the Australian National University.