The value of nature

Abstract

According to many accounts we are in the midst of a major extinction crisis, one that is unrivaled in extent and pace in evolutionary history. Despite enormous energy and expenditure devoted to conservation, we will be unable to save all imperiled species and places. How can (or even should) we come up with a prioritization approach that helps us make decisions about what is worth saving? One of the most widely promoted schemes is monetary valuation of species and ecosystems, based on the goods and services that we as humans receive. These ecosystem services can be delivered directly (eg food, fiber, or beauty) or indirectly (eg water filtration, carbon capture). While some have advocated monetary valuation as a democratic process in deciding which species or places to conserve (Nunes and van den Berg 2001; Ecol Econ 39: 203–22), others consider this a “selling out” of nature (McCauley 2006; Nature 447: 27–28). The important question is, can the economic model of anthropocentric valuing of species, ecosystems, and their goods and services deliver conservation benefits as promised? I propose a performance-based assessment using successes and failures over the past several decades, when the economic model has reigned supreme. Although space limitations prevent a detailed accounting here, I choose two crude metrics: protecting species and protecting ecosystems. Evidence suggests that we are doing rather poorly on the first, given accelerating species loss. Conversely, using protected areas, we have done better, by currently placing 12% of the global terrestrial surface area under some level of protection, with a goal of 20% by 2020. However, this growth in protected areas essentially “locks up” these places in conservation and out of the “normal” marketplace, so their applicability to assess performance of monetary evaluation is questionable. Furthermore, setting areas aside for conservation alone may not result in desired conservation benefits – we can't squeeze all of Earth's terrestrial biota into 10% or even 20% of the available area. Moreover, many protected areas are largely rock and ice (that is, not the most productive habitats) and global change will require many species to relocate. While I'm unable to judge whether – in the absence of the economic conservation model – biodiversity would have fared even worse, the status quo can't be one of comfort and promise for the future. I believe that any economic valuation of species or ecosystems will clash with long-term conservation goals. The most formidable obstacle is that managing species and ecosystems based on their utility to humans requires accurate measurements of the services that are provided and a thorough accounting of all costs and benefits. This raises serious questions about the ecological knowledge required to make such decisions. The economic value we assign to species will shift based on available information about the functional roles of species in ecosystems or food webs. For instance, we now recognize the role of top predators as structuring forces in terrestrial and aquatic environments, yet we do not assign them appropriate economic value. Non-lethal diseases and many parasites are now increasingly appreciated for their beneficial effects, for example in priming our immune systems. Any conservation approaches built on market-based evaluations rooted in past or incomplete ecological knowledge could result in extinction of species we undervalued previously. Furthermore, it is unclear how costs and benefits are being apportioned (locally, regionally, nationally, or globally). This raises serious questions about issues of accounting, governance, and enforcement, as well as the length of time economic models need to cover to account for cumulative or long-term effects. Finally, assigning trust and power to unregulated, market-based institutions to manage conservation interests implies that theoretical foundations, institutional structures, and their governance are sound and can be relied upon. The recent global financial crises indicate the opposite, because short-term profit maximizations overrode long-term stewardship responsibilities. While humans will clearly continue to be the beneficiaries of ecosystem services, the only hope for long-term conservation is to increase societal support. This requires a redefinition (in non-market terms) of our relationships with the natural world (including other people). In fact, this may provide the only means to assure the survival of many species and biotic communities for which we (currently) have no use or value. I agree with Aldo Leopold in that I have no hope for recruiting future generations of conservation-minded individuals by appealing to their pocketbooks. Instead, we should strive to reach their hearts. A nation does not buy conservation but learns it.