The relevance of plant translocation as a conservation tool in France

Abstract

The practice of plant translocations to mitigate the deleterious human effects on biodiversity has been increasing over the last decades. In France, although translocations are planned as conservation actions, there is no study that reviews conservation and protection status of translocated species, or that examines the identified threats to the populations for either mitigation-driven (as part of a regulatory mitigation process) or conservation-driven (outside the mitigation context) translocations. Using the TransLoc database, we compiled data on 436 translocated plant populations in France to determine the level of endangerment of the 193 translocated species using the French National Red List of vascular plant species, and their national and regional protection status. We also examined the identified threats to the populations following the IUCN threats classification scheme, and compared mitigation and conservation-driven translocations according to the reported threats and the regions of translocation. There were less mitigation than conservation-driven translocations overall (142 vs 229 respectively), with large differences between regions. We detected large and significant differences between mitigation and conservation-driven translocations in the local threats affecting populations. For mitigation-driven translocations, the most frequent threats were (i) transportation and service corridors and (ii) residential and commercial developments, while for conservation-driven translocations it was (i) human intrusions and disturbance, and (ii) natural system modifications. Approximately one third of the translocated species were nationally protected and two thirds were regionally protected (34% and 72%, respectively). In the IUCN red list, only 14% of the translocated species were considered threatened (CR, EN, VU) at the national level and 33% at the regional level. This result reflects the fact that conservationists are reluctant to use translocations as a means of conservation for the most threatened species, because they require a lot of work, a lot of information on the biology and ecology of the species, and their results are very uncertain, in contrast to habitat protection, which is generally considered the best way to protect species.