After millions of years of evolution from ancestors in or before the dinosaur era, the Wollemi Pine is teetering on the edge of extinction. Human beings are the biggest threat to its survival. One visitor to the site could destroy the population by introducing pathogens, for example a root fungus.
Translocation
Establishing a new population of Wollemi Pines at a new location had been an aim of the Wollemi Pine Recovery Team for a long time. Why? The four sites with Wollemi Pines are all in the same catchment in the Blue Mountains, and so the risk of losing the entire wild population of Wollemi Pines in a single catastrophic event, like a fire, is high. Establishment of a new population some distance from the original population reduces this risk, following the principle of “don’t keep all your eggs in one basket”.
One hundred and ninety-one Wollemi Pines were planted at a new site in August 2012. The translocation site was chosen because it matched the warm temperate rainforest community characteristic of the wild site, and had land tenure that was secure in the long term. Because of our research indicating that seedling growth increased with light, at the translocation site we planted the seedlings along a light gradient, from deep in the rainforest (similar to the wild site) up to the woodland-rainforest edge.
So far, the survival rate of the translocated seedlings is 83% - with higher survival where there is more available light. Moreover, some plants have shown growth rates of almost 30 cm (in height) per year, this is much greater than the 1-2 cm per year seen in the wild. Monitoring of the translocated population is ongoing, and we can’t wait until these plants grow to produce seedlings of their own.
Papers
- *Zimmer H C, *Offord C A, Auld T D & Baker P J, 2016, ‘Establishing a wild, ex situ population of a critically endangered shade-tolerant rainforest conifer: A translocation experiment’ PLOS ONE | DOI:10.1371/journal.pone.0157559
* indicates staff and students of the Royal Botanic Gardens Sydney
See also