Publications

Action 8: Establish new populations of endangered Caladenia taxa in the wild

For many endangered Caladenia taxa known from single or very few populations, the risk of extinction in the wild from lack of population vigour or from a stochastic disturbance event remains very high. This is particularly so for taxa that are unreserved. In order to reduce this risk it will be necessary to establish new populations at other sites.

Techniques are currently being developed at KPBG that are expected to greatly improve the probabilities of success of plant transfer into new areas (K. Dixon, KPBG, pers. comm.). It is intended that these techniques will be further developed as part of the current recovery plan. The aim of recovery will be to develop at least one additional self-maintaining population of each endangered Caladenia taxon in at least one protected reserve area.

8.1 Assess habitat preferences and select introduction sites

There are good quality habitat data available for several taxa but more detailed habitat information will be collected for other taxa from present and known former sites to define habitat preferences for each taxon. Data to be collected will include associated species, vegetation structure, geology and soils, rainfall and disturbance history.

The selection of suitable sites for introduction will need to consider a range of variables including site size, habitat, threats, management, land tenure and security. Where applicable, a range of introduction sites will be selected across the former range of the taxon to enable maintenance of regional genetic diversity pending the results of Action 6.2. 1: 100 000 Ecological Vegetation Class mapping (NRE in prep.) exists for the majority of sites containing populations of the twelve threatened Caladenia in Victoria as does floristic vegetation mapping of South east South Australia (Croft et al. 1999). These sources will be used to identify potential habitat and re-introduction sites.

Funds are required in years 2 and 3 of recovery to cover the salary and associated field/travel costs (eg. vehicle hire, travel allowance, consumables) of a project officer to collect and collate key data for the selection of introduction sites for each endangered Caladenia taxon. Land management agencies will cover the cost of staff involved with the selection of appropriate sites within reserves while state departmental staff will assist with the collection and collation of regional datasets such as disturbance histories.

8.2 Prepare reintroduction plans and establish plants at sites

A reintroduction plan will be prepared for each endangered Caladenia taxon, detailing any preparation of cultivated plants prior to reintroduction, methods of reintroduction (including using seed, tubers, seedlings or mature plants), timing, numbers of plants, experimental design, permanent marking grids and photo-points, monitoring techniques and frequency and other information as required.

Plants will be introduced to re-introduction sites following the guidelines set out in the reintroduction plans. The action requires the successful integration of horticultural and ecological experience, and will be undertaken by a specialist contractor, under contract to NRE. The contractor will be required to fully consult with all relevant land management agencies (eg. Parks Victoria) and interest groups.

Funding will be sought for years 4 and 5 of recovery to cover the costs of appointing a contractor to prepare reintroduction plans for all endangered taxa and to oversee the establishment of new populations, including site protection works such as weed control, pest animal control and/or fencing. Some funding will also be required in years 2 and 3 to implement re-introduction of taxa that are ahead of this general schedule (eg. C. amoena). Relevant land management agencies and regional threatened Caladenia community groups will be involved in the site preparation, planting, future monitoring and management of sites as detailed in the introduction plans.