Climate change will present new challenges to achieving ecosystem conservation and sound management of natural resources. Thanks to climate change, some species will increase, others will decrease, and the productivity of ecosystems will shift in ways that are difficult to anticipate. (A recent paper about how profound these changes might be, and how unprecedented, can be found here.) When species that we do not like (or are harmful to us and other species) increase, or when species that we use or appreciate decrease, we might want to take action. We might want to counteract those changes if we can. We call this climate change adaptation.
In this post, I discuss whether or not the discipline of conservation biology is up to the challenge of climate change adaptation using the tools that it already has. In other words, can conservation as we know it--the conservation tool kit that we already have--successfully combat the effects of climate change? I'll summarize the argument for both sides, but I think that the "no's" have it, at least for now.
First, we need to define what we mean by "successfully combat." Others may have different opinions, but I think that the best that we could hope for is achieving two things: 1) minimize biodiversity losses, including the extinction of species and the reduction of genetic diversity, and 2) maintain functioning ecosystems that provide benefits for humans, including water purification, recreational opportunities, and productive fisheries and forests. So now let's ask the question again: Is the current state of conservation biology, and the current management that we apply to ecosystems, enough to counteract the effects of climate change and achieve #1 and #2 above?
We already know what needs to be done to conserve biodiversity and maintain healthy ecosystems. To minimize the negative effects of climate change, we simply need to do these things more and better and over larger geographic areas. Specifically, we need habitats that support populations that are large enough to dip from random disturbances and climate change without going extinct. We also need these habitats to be connected over large geographic areas so that species can move naturally as the climate changes and relocate to keep up with changing climatic conditions. We know that rampant invasive species can directly consume or compete with species that we value and reduce native population sizes. Therefore, we know that we need to control many invasive species.
In the last several decades, we have identified relatively few new techniques for doing (and succeeding) at natural resource conservation. Captive breeding and zoos have become increasingly important, but they are not a substitute for maintaining large amounts of high quality habitat in the wild. In fact, most zoo programs count on the fact that habitats will be sufficiently restored for large-scale reintroductions. We have learned quite a lot about the relationship between people and nature and how to incentivize conservation. In many cases, we even need people and their economic activity to enable and advance conservation (e.g., sustainable timber harvest in a park to justify forest preservation). We also have identified new reasons to do conservation, including the potential to partially counteract greenhouse gas emissions through carbon uptake of forests and other vegetation. But the basic rules remain the same--maintain large, connected places with lots of buffering capacity so that local disturbances, and now climate change, have minimal long-term effects.
No--it is not
While the basic necessities for conservation are quite simple, it's unlikely that we can deploy traditional approaches enough to keep pace with the ecological effects of climate change. Some people think that only parts of conservation biology that truly count as "adaptation" are actions that are *different* than what we were doing before, something beyond business as usual. This implies that most standard conservation practices (e.g., setting aside land, managing invasive species) are not enough because they do not explicitly take steps to counteract climate change. Still, it is possible that our traditional practices could be adjusted according to climate change, such as doing prescribed burning earlier or later in the year as the seasonality of an ecosystem changes. Strategies for controlling an invasive species might also be altered if the invasive benefits from climate change. For example, hand pulling might have kept a species in check in the past but chemical control might become necessary with climate warming.
But even if we made adjustments to the toolbox so to that we use hammers and screwdrivers in ways that we did not use them before. Is that enough, or do we need new approaches all together? Overwhelming scientific data suggest that Earth's ecosystems are already under considerable pressure. Despite the existence of conservation biology, for example, the biodiversity crisis--the growing list of endangered species and increasing number of species that go extinct--continues and may be accelerating. Land is increasingly converted to agriculture, urbanization, or other uses that conflict with conserving large tracts of native habitat. Many of our endangered species already have small populations, probably too small to handle the additional stresses of climate change. And it seems unreasonable that massive new corridors would be established over areas such as the agricultural Midwest or urban, coastal California so that species could use these corridors for migration under climate change. There also are some data to suggest that select invasive species, because they are hardy and disperse more easily than native counterparts, might do better under climate change than they did in the recent past. This could lead to a weedier world, and controlling those invasive species could become harder, more time consuming, and more expensive. Given budget constraints, it also seems unlikely that we can just grow the scale of conservation operations, including land acquisition and the number of personnel needed to monitor and manage species adjusting to climate change. If we are already loosing ground without climate change, how can doing more of the same be sufficient?
If it's not enough, then what?
If conservation as we know it cannot keep up, then what? First, we can argue for the expansion in conservation monitoring and activities that would be necessary for it to try to keep up. We need a great deal of research to figure out how to adjust traditional tools to fit with changing climate, and we need an expanded commitment of resources and land to deal with the worldwide threat of climate change. Second, we will need new ideas that directly address the threat of climate change and overcome problems that are insurmountable with traditional approaches. These could include looking for conservation opportunities in non-traditional places, such as in urban parks and backyards. It could include moving particularly vulnerable or valuable species to new areas (where the risks of doing so are acceptable), and it could involve traditional or high-tech breeding to introduce resistant genes or facilitate evolution to changing climatic conditions. We may even need to change our definition of nature itself so that biodiversity conservation happens in more places than just wilderness and higher degrees of human intervention are tolerated for the benefit of particular species and ecosystems that really need it. These things will eventually create a conservation biology that looks very different than it does today.