Two decades of plant translocations in Western Australia: Assessing success and recovery of threatened species

Background/Question/Methods

Plant translocations, the movement of plant material for conservation purposes, have been used as part of species recovery programs in Western Australia for the past two decades. In this time the Department of Environment and Conservation translocated 58 taxa to 94 sites. These translocations have predominantly been set up as experiments, under an adaptive management framework, to improve establishment and success rates. This approach has also been used to develop success criteria which can subsequently be applied in a re-assessment of the species conservation status.

An overarching success criterion for these translocated populations is that they are self-sustaining. Only then can they be considered when ranking the conservation status of that species. Many of the species in Western Australia’s translocation program are long lived, take many years to reach maturity, and may take years (or require a disturbance event) before subsequent generations are recruited. This makes developing long term success criteria challenging. Consideration is now being given to surrogate measures such as predictions based on PVA, and benchmarking genetic diversity and mating system estimates of translocated populations against natural populations. Alternatives, such as long term monitoring to confirm self-sustainability over multiple generations, are often not possible due to limited resources.

Results/Conclusions

In this talk we assess the two decades of data collected from the 94 translocation sites. We discuss the results from the experiments designed to test establishment techniques, in particular the survival and growth data from watering, mulching and vertebrate herbivore exclusion experiments. We examine whether any of our 94 translocations can be considered successful and in light of these reviews, evaluate the appropriateness of our success criteria. We also assess the contribution made by translocated populations to the overall conservation of threatened plant taxa.