National recovery plan for Twelve Threatened Spider-Orchid Caladenia R. Br. Taxa of Victoria and South Australia 2000 - 2004
James A. Todd
Department of Natural Resources and Environment, Victoria
Flora and Fauna Statewide Programs, March 2000
Summary
Current Species Status
Ten of the twelve Caladenia taxa addressed in this plan are currently listed as Endangered under Commonwealth endangered species legislation, the list of threatened species maintained by the Endangered Flora Network of ANZECC and the IUCN Red List (Walter and Gillet 1998). The remaining two species are listed as Vulnerable under the same lists. Subsequent revisions of these lists will take account of the new information summarised in this plan, which recommends that Caladenia tensa be re-categorised from endangered to vulnerable and Caladenia versicolor be re-categorised from vulnerable to endangered.
Habitat Requirements and Limiting Factors
The threatened Caladenia taxa occupy a range of different habitats. Five of the taxa (C. formosa, C. lowanensis, C. tensa, C. versicolor and C. xanthochila) occupy dry woodlands of western Victoria and southeast South Australia mostly on Quaternary sand deposits. Three taxa (C. amoena, C. audasii and C. rosella) occupy box-ironbark forests and woodlands of inland Victoria on sandstone. Three taxa (C. fragrantissima ssp. orientalis, C. robinsonii and C. hastata) occupy near coastal heaths and heathy woodlands of eastern and western Victoria while C. thysanochila occupies grassy woodlands on granodiorite on the Mornington Peninsula.
A defining feature of most of the species is that they occupy uncommon habitats. These may have been naturally uncommon prior to European settlement, or more typically, because of clearing for agriculture and urbanisation since European settlement. Most species occur within severely fragmented ecosystems that are subject to a range of potentially threatening processes typical of such environments. These include weed invasions, grazing by native and introduced herbivores, inappropriate fire regimes and damage to populations by recreators.
Recovery Goals and Criteria
Short-term Goal: ensure that all existing populations are adequately protected; increase the numbers of plants in the wild; establish a genetically representative ex-situ collection of endangered taxa in cultivation; increase the number of populations in the wild; and raise public awareness and foster community involvement in this process.
Recovery Criteria
The criteria for assessing the achievement of this Goal are:
- Determination of the conservation status of all taxa in the wild;
- Establishment of a private and public land protected area network for threatened Caladenia taxa;
- A measurable decrease in the number and magnitude of identified threats to populations;
- An increase in the abundance of vulnerable taxa to at least twice current numbers;
- An increase in abundance of endangered taxa to at least 5x current numbers;
- Identification of key components of the biology and ecology of threatened Caladenia taxa;
- Development of successful propagation techniques and the establishment of at least 100 plants of each endangered taxon in the wild;
- Establishment of at least one additional population of each endangered taxon in a secure reserve in the wild; and
- Increased community involvement in pivotal aspects of criteria above.
Long-term Goal: to achieve secure, representative, self-sustaining metapopulations of all twelve threatened Caladenia taxa in the wild.
Recovery Criteria
The criteria for assessing the achievement of this Goal are:
- Achieving successful natural pollination, establishment of seedlings and recruitment at each population site for each taxon; and
- The protection of at least two populations of each taxon in nature conservation reserves.
Recovery Actions
Action1 Determine the conservation status of the twelve threatened Caladenia taxa in Victoria and South Australia- Identify and verify populations
Action 2 Protect identified Caladenia habitat
- Identify key populations for protection
- Protect key public land populations
- Protect key private land populations
Action 3 Protect populations from high-risk threatening processes
- Control high-priority weed species
- Control animal pests and predators and investigate grazing impacts
- Recover populations by fire and further investigate fire ecology
- Control the spread of Cinnamon Fungus
Action Develop and initiate fine-scale site management practices
- Hand pollinate plants
- Harvest and store seed
- Manage microhabitat
Action 5 Measure population trends and responses against recovery actions
- Conduct annual censusing
Action 6 Investigate the biology and ecology of threatened Caladenia taxa
- Identify the pollinator and determine natural pollination levels
- Determine the genetic relationships of disjunct populations
- Investigate germination and seedling establishment
Action 7 Establish ex-situ collections of threatened Caladenia taxa with rapidly declining or critically low populations in the wild
- Isolate and culture mycorrhizal fungi
- Develop in vitro propagating techniques and establish seedlings in cultivation
- Maintain a database on cultivated plants
Action 8 Establish new populations of endangered Caladenia taxa in the wild
- Assess habitat preferences and select introduction sites
- Prepare reintroduction plans and establish plants to the wild
Action 9 Develop a public education/community extension program
- Prepare education material and undertake community extension
Action 10 Manage recovery plan implementation
- Expand the Threatened Orchid Recovery Team (TORT)
- Establish a regional recovery team for each taxon
- Prepare and review the Victorian FFG Action Statements for various threatened Caladenia taxa
Estimated Cost of Recovery
|
Action |
2000 |
2001 |
2002 |
2003 |
2004 |
Total |
|
1 |
$20,170 |
$18,670 |
$0 |
$0 |
$0 |
$38,840 |
|
2 |
$0 |
$20,230 |
$15,400 |
$0 |
$0 |
$35,630 |
|
3 |
$32,840 |
$25,270 |
$21,300 |
$26,550 |
$26,550 |
$132,510 |
|
4 |
$16,630 |
$17,830 |
$17,580 |
$17,580 |
$17,580 |
$87,200 |
|
5 |
$33,360 |
$36,810 |
$36,810 |
$22,850 |
$22,850 |
$152,680 |
|
6 |
$0 |
$46,215 |
$46,215 |
$0 |
$0 |
$92,430 |
|
7 |
$1,000 |
$22,500 |
$22,700 |
$10,200 |
$1,200 |
$57,600 |
|
8 |
$0 |
$14,590 |
$14,590 |
$10,290 |
$10,290 |
$49,760 |
|
9 |
$42,100 |
$42,100 |
$0 |
$0 |
$0 |
$84,200 |
|
10 |
$10,950 |
$9,040 |
$14,040 |
$10,950 |
$10,950 |
$52,110 |
|
Total |
$157,050 |
|
$188,635 |
$96,510 |
$87,510 |
|
(Note: the year refers to the financial year, not calendar year ie. 2000 refers to the 12 months from July 2000 until June 2001).
Biodiversity Benefits
The recovery of the twelve threatened Caladenia taxa has a number of potential biodiversity benefits for other species and vegetation communities in Victoria and South Australia. Principally, this will be through the protection and reservation of habitat that would be otherwise unreserved. The adoption of broad-scale management techniques will also benefit a number of other plant species growing in association with the threatened Caladenia taxa, particularly those species with similar life forms and/or flowering responses (eg. lilies, orchids).
The recovery of the twelve threatened Caladenia taxa will also form an important public education role as spider-orchids have the potential to act as 'flagship species' for highlighting broader nature conservation and biodiversity issues such as land clearing, weed invasions and habitat degradation. Germination and cultivation techniques developed during the recovery phase will be of use for other threatened Caladenia taxa elsewhere in southeast Australia while the requirement to recover taxa across state boundaries will better develop working relationships between state departments on a broader range of biodiversity conservation issues.