(Janzen, 2000). This process has several names—restoration, rewilding, renaturalization—and provides a constructive, creative counterpoint to the stop-loss approach of traditional conservation. Thus, the future of biodiversity is not just what we can save of what is left, but also what we can create from what is left [see also Soule and Terborgh (1999)]. As Young (2000) put it, “The conservation mindset is one of loss on a relatively short time horizon, whereas the restoration mindset is one of long-term recovery.”
Successes abound. The regeneration of tropical forest in Guanacaste Province, northwestern Costa Rica (Janzen, 2000, 2002), is particularly heartening for several reasons: it involves restoration of multiple habitat types; it is large-scale yet local and decentralized; and it was achieved by using a portfolio of innovative mechanisms and via broad collaboration among scientists, businesspeople, politicians, and the local community. The result has been the regeneration and conservation of 700 km2 of tropical dry forest along with abutting chunks of rain and montane forest. In poverty-stricken Niger on the fringe of the Sahara, farmers have helped hold off desertification in many areas by nurturing saplings in their fields rather than removing them—and they have begun to reap benefits from this greening of the countryside (Polgreen, 2007). In the oceans, researchers have had some success transplanting live coral fragments onto degraded reefs (Guzman, 1991). Likewise, efforts to rebuild damaged watersheds and wetlands have been a major focus of scientific restoration ecology [e.g., Mitsch and Wilson (1996)], with important implications for the availability of potable water.
Large animals are particularly extinction-prone, at both the population and species levels. They are also often particularly important to ecological dynamics. Returning megafaunal species to what remains of their historical ranges (Donlan et al., 2006) can yield a number of overlapping benefits: the return of these charismatic species undoes population extinctions, makes habitats more interesting and exciting, and can restore ecological interactions with appealing systemwide consequences. The repatriation of wolves to Yellowstone National Park in 1995 not only titillated tourists but also revived a multispecies trophic interaction involving elk, beavers, and trees, which has rejuvenated the region’s riparian ecosystems (Ripple and Beschta, 2007b; Wolf et al., 2007).
These examples and others illustrate that ecological restoration has a critical role in determining where biodiversity goes from here; we hope for enormous and rapid expansion of such revival efforts, even if the ultimate ecological goals take centuries to achieve. The only caveat is that many projects branded as “restoration” may be only weakly beneficial or neutral for biodiversity (Zedler and Callaway, 1999). Tree plantations are not forests.