Loss of habitat through ecosystem degradation and land use change is one of the major causes of threat to wild plant populations. Habitat restoration is one approach that may allow plant populations to recover without the use of introduced propagules. However, spontaneous recovery of rare plant populations in restored sites may be constrained by the absence of naturally occurring propagules. In this case, the reintroduction of individual plants in the wild is an essential measure to ensure the in situ conservation of threatened species.
The ultimate objective of a reintroduction programme is to establish or reinforce viable, self-maintaining populations of the selected species, so that it will persist for an ecologically significant period of time. The placement of plant material into the landscape is thus undertaken with the goal of integrating these plants and their progeny into a functioning ecosystem.
Reintroduction as a means of restoring or increasing the viability of plant populations is not an easy exercise. The procedures are long-term, time-consuming and expensive, and if their application is to be considered as a valid conservation exercise, require rigorous control.
It is important to ensure appropriate environmental studies are carried out as the basis of reintroduction programmes. Such studies should include:
Wallace (1992) suggested a series of practical criteria that could be applied before a reintroduction programme is initiated:
A range of guidelines on plant introductions are available – such as those available provided by the IUCN/SSC Re-introduction Specialist Group and BGCI’s Handbook for Botanic Gardens on the Reintroduction of Plants to the Wild.
Ecosystem restoration is the process of actively managing the recovery of an ecosystem that has been degraded, damaged or destroyed. It is a conscious intervention based on traditional or local knowledge and scientific understanding. Its goal is to restore ecosystems to be resilient and self-sustaining with respect to their structure and functional properties.
More background information on ecological restoration is available here, including principles of good ecological practice, developed by the Society for Ecological Restoration (SER) and IUCN, based on experience gained over several decades and consistent with the principles of the Ecosystem Approach of the CBD.
Effective implementation of restoration projects requires an array of tools, best practice and guidelines. A wealth of tools, useful good practice cases and practical guidance is currently available at a variety of spatial scales and levels of specificity depending on the targeted end-user.
An Ecological Restoration Alliance of Botanic Gardens has been established to share best practice and build capacity for restoration work in botanic gardens. More information, including case studies of ongoing projects is available on the website: www.erabg.org.
SER has published detailed guidelines for developing and managing ecological restoration projects. These are available for download from their website in English, Portuguese and Italian.
Information relevant to the restoration of specific ecosystems is also available: