Photo: Jonathan Rhodes.
By Jonathan Rhodes, Yan Liu, Agung Wahyudi, Martine Maron, Sayed Md Iftekhar, and Shantala Brisbane.
One major challenge for conservation is understanding how we protect species in landscapes that humans are rapidly transforming. A solution popular with governments around the world is biodiversity offsets, where developers must compensate for the biodiversity losses that they cause by creating biodiversity gains elsewhere. Yet, offsets are controversial because they are often ineffective and lead to ongoing losses of biodiversity.
This paper identifies the upsides and downsides of a strategic investment approach to offsetting a landscape being rapidly transformed by people. Most offset policies only use habitat metrics, such as habitat area, as proxies to estimate biodiversity losses and gains in each offset trade. Yet, this doesn’t necessarily guarantee gains in species abundance and offset sites sufficiently offset losses at impact sites. But if we could carefully make strategic choices about the location of offsets sites this limitation could potentially be overcome and improve offset outcomes for species. By integrating new models of human land-use change, species distributions, and policy settings, we show that governments could improve offset outcomes for species’ abundance if they invest financial contributions from developers strategically to deliver offsets. However, a downside is that the government then takes on the financial risk of delivering offsets on the developer’s behalf and can expose itself to having insufficient financial resources to match habitat losses with equivalent gains. This risk was found to be particularly high when finding potential locations for offsets sites is difficult.
Our findings are based on the application of our models to a koala (Phascolarctos cinereus) offset policy in South East Queensland, Australia where koalas are threatened by urban development and habitat loss. This has helped to identify new insights into how to design offset policies for the conservation of this iconic species in the region. Yet, the integrated models developed provide a general framework for evaluating offset policies in real landscapes where there are complex interactions between human land-use change, ecological processes, and policy processes.
Relational Thinking 