Lofty Block Threatened Orchid Recovery Project
About the Project
The Lofty Block Threatened Orchid Recovery Project is a community-based conservation project that has been operating since 1998. The main aim of the project is to plan and implement the recovery of nationally threatened orchids in the Lofty Block region of South Australia (see map of project area and distribution of threatened orchids (600Kb PDF)). The project currently manages twelve orchid species, which are listed below:
The project is currently funded by the Department for Environment and Heritage, Commonwealth Department of the Environment and Water Resources, Adelaide & Mount Lofty Ranges Natural Resource Management Board, and the Northern & Yorke Natural Resource Management Board. The Threatened Plant Action Group and the Native Orchid Society of South Australia are key project partners; both groups contribute significant amounts of volunteer time, skills and expertise to the project. Recovery PlanningIn 2006 a recovery plan for the twelve species was completed (Recovery Plan for Twelve Threatened Orchids in the Lofty Block region of South Australia 2002-2012 (1.3Mb PDF)). The plan provides detailed information about each of the twelve species covered by the project. Importantly, it prescribes recovery objectives aimed at improving the conservation status of each species in the long-term, including:
Two recovery teams comprised of government staff, scientific experts, members of community conservation groups and landholders oversee the management of the project. Threats to RecoveryAll of the orchid species covered by the project are subject to a wide range of threats, which are collectively contributing to species decline. Implementing on-ground threat abatement actions is an important part of the recovery project. Some of the key threats are described below: Climate ChangeClimate change is a serious long-term threat to many of the orchids covered by the project. These species have limited capacity to adapt to changes in the average climate, especially decrease in average annual rainfall, and increase in average annual temperatures, as is predicted for much of South Australia. Vegetation ClearanceVegetation clearance has resulted in the loss and fragmentation of habitat for the species covered by the project, and has contributed to the extinction and decline of many orchid populations. A large number of the orchid populations occur in small isolated remnants of vegetation, and have limited capacity for transfer of pollen and seed between populations. Weed Invasion
Weed invasion directly impacts on the growth, recruitment and survival of many of the orchid populations covered by the project through competition for space, light, nutrients, and moisture. Highly invasive environmental weeds such as Bridal Creeper, Montpellier Broom, Boneseed, Watsonia, Sweet Pittosporum, and Topped Lavender are particularly problematic. HerbivoryHerbivory (grazing or browsing) by native and introduced animals, including kangaroos, rabbits, sheep, cattle, deer, possums, birds and invertebrates is a serious threat to many of the orchid populations covered by the project. Browsing of flowers is particularly damaging as it prevents the possibility of pollination and seed set. Lack of PollinationMany of the orchid populations covered by the project have low levels of pollination and seed set. This is thought to be caused by the decline or extinction of pollinators through habitat loss, pesticide drift, and competition with honeybees. Many orchids have specific pollinator species, therefore a decline in pollinators can be a limiting factor for these species.
Road and Track Management
Many of the orchid populations covered by the project occur in roadsides and along track verges. Management of these roads and tracks often conflicts with orchid conservation. Activities such as grading, widening, bituminising, stockpiling materials, constructing turnout drains, and spraying herbicide can all cause damage to orchid populations. Illegal CollectionMany of the orchids covered by the project are at risk from illegal collection. These species are sought after by orchid growers, and are occasionally taken from the wild for private collections. All of the species in the project are protected under Commonwealth and State legislation and cannot be taken from the wild without a permit. They are also listed under CITES (Convention on International Trade in Endangered Species) which controls international trade in wildlife. On-ground Recovery ActionsThe recovery plan also outlines the actions needed to achieve the recovery objectives. Some of the key on-ground recovery actions being undertaken are described below: Surveys and Monitoring
Population surveys are undertaken at over 100 sites to monitor the size of orchid populations, and to evaluate the success of recovery actions. Targeted surveys of historical and potential habitat are also being undertaken. These have already resulted in the discovery of 43 additional orchid populations between 1998 and 2007. Annual monitoring of individual orchids is also undertaken at over 50 sites to determine the rates of flowering, pollination, seed set, seedling germination and establishment, and herbivory within orchid populations. Knowledge about the demographics of the orchids covered by the project is generally poor, and requires ongoing studies. The data gained from population surveys and monitoring are vital for determining population trends, and predicting the likelihood of species recovery and long-term survival. This information also provides the basis for evaluating the effectiveness of the recovery actions. Weed Control
Weed control programs are undertaken in over 40 orchid populations to prevent weeds from displacing the orchids and continuing to modify habitat critical to survival. Minimal disturbance 'bush care' methods are used to control weeds around the orchid populations to prevent off-target damage. These include hand pulling or grubbing out weeds, and other techniques that use minimal herbicide such as 'cut and swab' (cutting the stems of woody weeds and applying herbicide directly to the cut stem) and 'drill and fill' (drilling holes in the stems of woody weeds and applying herbicide directly into the holes). Herbicide use around orchid populations is generally avoided when the orchids are actively growing (often in spring). Herbivore ControlRabbit control programs are undertaken in over 10 orchid populations to reduce the level of herbivory. Regional kangaroo management programs have also helped to protect threatened orchids.
Stock-proof fences are installed around more than ten orchid populations to reduce herbivory and trampling of threatened orchid populations, and to prevent habitat degradation. This is often supported by Natural Resource Management On-ground Works funding programs. Kangaroo and rabbit proof fences are installed around three orchid populations to protect them against herbivory. The University of South Australia has undertaken ongoing monitoring of herbivory within and outside these exclosures since 2000. Wire-mesh cages are placed around plants in over 30 orchid populations to protect them from herbivory by rabbits, hares, kangaroos, and other hebivores. Seed Collection and propagationSeed has been collected from more than 100 orchid populations for long-term storage at the Botanic Gardens of Adelaide. The mycorrhizal fungi (soil-based root fungi) required to germinate the seed is also being collected and stored. Specialised techniques for germinating the seed in symbiosis with the fungi are being tested for each of the species covered by the project. Successfully germinated seedlings will be cultivated, and may be used for re-introductions into the wild in the future. Hand pollination of orchid flowers is sometimes undertaken to enhance seed-set in orchid populations that have low levels of natural pollination and seed-set. Ecological Disturbance Trials
Studies are being undertaken at some sites containing the species covered by the project to determine whether certain types of disturbances are required to stimulate orchid flowering and recruitment. Many species of native orchids flower prolifically after fire, and germinate after soil disturbance. Some of the spider-orchids covered by the project are known to respond favourably to fire or soil disturbance. However, some of the greenhood orchids are known to decline after fire. Community InvolvementThe Lofty Block Threatened Orchid Recovery Project is a community-based recovery program involving more than 15 community groups. Over 60 volunteers are involved with the project each year, including members of the:
Getting InvolvedAnyone can become a volunteer for the project. Volunteers are involved in a range of activities including surveys, monitoring, weeding, caging, fencing and other recovery actions. If you are interested in becoming involved or would like more information about the project please contact the Department for Environment and Heritage (see contacts below). Author/ContactJoe Quarmby, Project Officer, Threatened Orchids, Department for Environment and Heritage |
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