In his 2016 book Half Earth, Dr. E. O. Wilson presents the global community with a challenge: set aside half of the Earth for nature. He articulates why this must be done – the ever-growing human population and its consumption have degraded natural ecosystems and created a crisis for Earth’s biodiversity. By working toward a goal of 50% protection, he argues, the conservation community can focus on a tangible number that can be tracked and communicated clearly. The Half Earth book presents protected areas – state-designated lands and waters – as the key to achieving this goal. It also briefly notes the important role of other area-based conservation strategies, including conservation easements and efforts by private individuals.
But many questions arise: Which half of the Earth? Which level of biodiversity do we prioritize to protect (genetic, species, ecosystem, or functional)? How do we include the high seas in this equation, which are outside of national jurisdictions? Do we focus first on biodiversity hotspots to save the most species? Mustn’t we also represent all of earth’s ecoregions, ensuring that the diversity of life forms are secure – including species-poor deserts and ice fields? And once protected areas are established, is that the end of the story? Are protected areas sustainable indefinitely? Does protection itself assure the persistence of biodiversity? And is it possible to achieve the Half Earth goal equitably for people?
To address these questions and hope to achieve the Half Earth goal, we need an interdisciplinary approach. We can start with biological sciences to map the distribution of species and ecosystems, for instance. Although we do not have nearly close to a census of all species on earth, nor a full understanding of genetic or functional diversity, published maps of species and ecosystems are likely sufficient to guide conservation efforts given the urgency of the biodiversity crisis. Next, we should consider the spatial distribution and status of protected areas – and other area-based conservation interventions – to track conservation progress. Accounting for the spatial and regulatory histories of protected areas and other conservation interventions is critical. By tracking past boundary changes, regulatory roll-backs, and upgrades to protected areas, we can more adequately understand the influence of political history, contextualize the economic demands and pressures on the area, and make more informed and sustainable decisions. The body of literature on protected area downgrading (regulatory weakening), downsizing, (reductions), and degazettement (elimination) or PADDD can help.
Notably, protected areas are not the only way forward. We must track and evaluate other conservation interventions, like indigenous lands, payments for ecosystem services, and market-based mechanisms. Syntheses of the effectiveness of all conservation interventions (via evidence maps, for instance) will be helpful to understand how far we have come and allow us to set future priorities.
Setting priority regions for conservation can be done in a variety of ways – based on biodiversity hotspots, gaps in protection (of species or ecoregions), or connecting existing protected areas by restoring corridors. Prioritization can be global, regional, national, or local; work at one level can also inform the others. An example of a spatial prioritization effort is the advent of Key Biodiversity Areas – regions representing a high diversity of species. The KBA framework also accounts for species endemism and vulnerability, as well as the “manageability” of territorial units, hence considering the current boundaries of protected areas. Notably, this does not consider the history of boundary changes nor loss of protected areas via downgrading, downsizing, and degazettement (PADDD), so it may ignore important lands that were previously protected but dropped from the estate due to industrial or local-scale pressures. Although KBAs represent a useful and science-based framework to guide conservation directions, national and local governments – as well as private individuals – will likely draw on a variety of approaches to determine priorities for protection. These will include convenience (determining which lands and waters, if protected, will lead to the least conflict with local people or industry) and self-interest (considering financial incentives from eco-certification or REDD+ and carbon markets).
As human pressures on the planet continue to accelerate and less arable land is available, for instance, the pressure for natural resources on the last wild places will continue to increase. The future of the siting of conservation interventions will likely be subject to negotiations and political bargaining. Striking a balance between the goal of half earth with the needs of local communities – for water, food, land, and energy – will take constant effort at all levels, from local management to international policy. Local communities can and should be empowered as stewards of the land to ensure that work toward half earth does not unjustly exclude or marginalize them. Without this critical piece, efforts to protect lands upon which people depend directly may backfire and become a source of resentment. Insights from anthropology can inform this dynamic. In the terrestrial sphere, in certain places, we may be reaching a point of saturation for strictly protected areas which exclude all human activities. In these cases, only by engaging with local communities – including indigenous and non-indigenous groups – can we hope to achieve large-scale conservation that is fostered and sustained for generations. Management of protected areas must also be prioritized to the utmost. In the marine realm, for instance, recent work shows that the most important determining factors of success in marine protected areas are adequate staff and capacity for management.
It is clear that “people power” to manage, monitor, evaluate, and steward protected lands and waters is now and will continue to be fundamental to achieving the goal of Half Earth. Continued investment in the social sciences in conservation and collaborations between natural and social scientists – economists, geographers, anthropologists, and even ethics scholars – can ensure that this goal is supported by a strong evidence base and can therefore be sustained.
Happy #HalfEarth Day! October 22nd, 2017 marks six months since the first-ever Earth Optimism event on Earth Day 2017. Earth Optimism emphasizes the importance of positivity in messaging and a focus on conservation solutions; only with this approach can the conservation community hope to engage and excite decision makers and the public to support and value conservation efforts.
On Half Earth Day, I was honored to share the stage with Dr. E. O. Wilson at an event at the Smithsonian Castle, discussing protected areas and the way forward for Half Earth.