Australian Plant Reintroductions
Grevillea scapigera
The Corrigin Grevillea (G. scapigera: Proteaceae) is one of the world's rarest plant species, currently known from 5 plants in the wild in the Western Australian wheatbelt. In 1995, 10 plants were selected from 47 plants known at the time to act as genetically representative founders for translocation into secure sites. Ramets were micropropagated and introduced into one of these secure sites (Corrigin) in 1996, 1997, and 1998. By late 1998, 266 plants had been translocated and were producing large numbers of seeds. With the development of an artificial seed-germination technique, and lack of seed germination in situ, seed was collected from these plants, germinated ex situ, and 161 seedlings returned to the field site in winter 1999. We used AFLP ( a DNA fingerprinting technique) to (1) assess the genetic fidelity of the clones through the propagation process, (2) contrast genetic variation and average genetic similarities of the F1s to their parents to assess genetic decline, and (3) assign paternity to the reintroduced seeds to assess the reproductive success of each clone. We found that (1) 8 clones, not 10, were present in the translocated population and 54% of all plants were a single clone, (2) the F1s were on average 22% more inbred and 20% less heterozygous than their parents, largely because (3) 85% of all seeds were the product of only four clones. Ne (effective population size) was therefore about 2. Such rapid genetic decline may be a feature of many translocated populations when Ne is small, and may threaten long-term survival. Strategies to reverse such genetic declines include equalizing founder numbers, adding new genotypes when discovered, promoting multiple siring and reducing kinship, promoting seed germination in situ rather than germinating seeds ex situ, and creating a metapopulation of numerous translocated populations. Contact Siegy Krauss.
Grevillea althroferorum
Just 298 plants of Grevillea althroferorum (split-leaved Grevillea) still exist in the wild. The species is restricted to two small and considerably disjunct populations (the populations are separated by 200km of mainly cleared farmland) north of Perth, Western Australia. In September 2005, the Department of Conservation and Land Management introduced 73 plants grown from cuttings to South Eneabba Nature Reserve. Although the species has never been recorded at this site the habitat has similar soils and associated vegetation. A watering system has been installed and half the plants will be watered over the first summer to assess the importance of watering to translocation success. Further planting is planned to ensure the population is viable. A long term monitoring program has been developed to assess the success of this planting. Contact Leonie Monks, Department of Conservation and Land Management, Western Australia.
Synaphea quartzitica
As its name suggests, the Quartz-loving Synaphea (Synaphea quartzitica) is found only on quartz and chert hills north of Perth. As it was only known from four populations a decision was made to find a new site with suitable habitat in a nature reserve. Such a site was found north of Watheroo (approximately 200 km north of Perth, Western Australia) and in August 2005 225 plants grown using tissue culture techniques were planted out. Similar to the Split-leaved Grevillea half the plants were watered and the other half left unwatered to assess the need for watering over the first summer. Further updates on this translocation will be available as part of the ongoing monitoring of the translocation. Contact Leonie Monks.
Lambertia orbifolia
A decision was made to translocate Round-leaf Honeysuckle (Lambertia orbifolia) after the species was split into two subspecies following genetic work. This meant that the form near Albany, Western Australia (subsequently named Lambertia orbifolia subsp. orbifolia) was listed as critically endangered because it was known from just two populations of 169 individuals, both of which are infected with aerial canker and dieback (Phytophthora cinnamomi). To date we have introduced 714 seedlings and cuttings into a nature reserve a few kilometers away from the known populations. The survival of the first three years of planting is 47% of the 615 plants (the last 106 seedlings were only planted in May so survival data is not yet available). The plants from the first three years have all grown, flowered and set viable seed and at last count 104 naturally recruited seedlings have been found – a positive indication that this population may be self-sustaining. Contact Leonie Monks.