National recovery plan for the Nightcap Oak (Eidothea hardeniana)
Threatened Species Unit, Western
New South Wales Department of Environment and Conservation, 2004
ISBN: 0 7313 6781 2
6. Proposed Recovery Objectives, Actions and Performance Criteria for the Nightcap Oak
- Specific Objective 1: Habitat Management
- Specific Objective 2: Research
- Specific Objective 3: Ex-situ conservation
The overall objective of this Recovery Plan is to protect known populations of the Nightcap Oak from decline by human-induced impacts, and to ensure that wild populations of the Nightcap Oak remain viable in the long-term.
Specific objectives of the Recovery Plan for the Nightcap Oak are listed below. For each of these objectives a number of recovery actions have been developed, each with a justification and performance criterion.
Recovery Action 1.1. Fire management
The DEC recommends that management aim to exclude fire from the Nightcap Oak habitat. The DEC will ensure that no new fire trails are constructed, or closed fire trails reopened, in the Nightcap Oak habitat. Fire Management Plan strategic placing of fire trails to protect species in the event of wildfire.
Justification: Fire is not likely to be necessary to promote regeneration of the Nightcap Oak and may have adverse impacts on the species as it occurs in rainforest habitat.
Performance Criterion: Fire is excluded from the Nightcap Oak habitat. No fire trails are constructed or reopened in the Nightcap Oak habitat. Fire Management Plan has mechanisms to protect the Nightcap Oak in wildfire event.
Recovery Action 1.2. Tourism
The DEC will not permit commercial tourism activities to be conducted in the Nightcap Oak habitat, outside existing roads or tracks.
Justification: The Nightcap Range area is subject to increasing recreational activity, particularly by commercial operators visiting with groups of various sizes. Commercial tourism has the potential to adversely impact on the Nightcap Oak and its habitat. This impact may be by physical damage to habitat or individual Nightcap Oak plants or by introduction of disease, pests and weeds.
Performance Criterion: No commercial tourism activities are conducted in the Nightcap Oak habitat outside existing roads or tracks.
Recovery Action 1.3. Site visitation and location confidentiality
The DEC will coordinate the development of a site access strategy. This strategy will detail conditions of access to the Nightcap Oak sites and the maintenance of the confidentiality of the locations of the Nightcap Oak. Access is to be limited to essential research and management purposes. The strategy will also investigate the production of film footage of the Nightcap Oak and its habitat to provide to commercial film operators who would otherwise want to access the sites.
Justification: There has been significant media and public interest in the Nightcap Oak since its discovery in 2000, which has led to increased visitation for reasons ranging from research to film making. Unrestricted access has the potential to adversely impact the Nightcap Oak habitat or individuals by physical damage or by introduction of disease, pests and weeds. In addition, illegal collection of plants or plant parts by enthusiasts may have adverse impacts upon the species. It is therefore necessary to both limit access to the Nightcap Oak and to maintain confidentiality about the location of the Nightcap Oak.
Performance Criterion: A site access strategy is developed. Film footage is produced.
Recovery Action 1.4. Weed management
Management will aim to maintain the current weed-free status of the Nightcap Oak habitat. If weeds are identified in the Nightcap Oak, the DEC will treat the area as a priority using appropriate techniques.
Justification: Weeds are not present in any known sites containing the Nightcap Oak. Weeds have the potential to outcompete the Nightcap Oak seedlings and adversely modify the Nightcap Oak habitat.
Performance Criterion: The Nightcap Oak habitat remains free of weeds that may adversely impact upon the viability of the species.
Recovery Action 1.5. Environmental assessment
Standard survey and environmental assessment guidelines for the Nightcap Oak will be developed and distributed to all relevant consent authorities.
Justification: A standard minimum survey effort should be undertaken when determining if the Nightcap Oak is present in or near an area of potential development. Presence of the species should require implementation of effective mitigation measures to reduce the impact of proposed development.
Performance Criterion: Standard survey and environmental assessment guidelines are developed and distributed.
Recovery Action 1.6. Investigation of listing of Critical Habitat
An assessment of the need to declare Critical Habitat for the Nightcap Oak under the TSC Act will be investigated in order to determine if it would produce any demonstrable benefits to the species.
Justification: A declaration of Critical Habitat under the TSC Act may deliver significant conservation benefits for the species.
Performance Criterion: Listing of Critical Habitat is investigated and pursued if appropriate.
Recovery Action 2.1. Survey
Targeted surveys for the Nightcap Oak in suitable habitat will be carried out. As extensive targeted surveys have already been undertaken, additional survey should be done opportunistically during any resource inventory work that is undertaken.
Justification: Additional targeted survey will assist with establishing whether any further individuals or populations of the Nightcap Oak exist.
Performance Criterion: Additional targeted survey is carried out during resource inventory work.
Recovery Action 2.2. Monitoring
The Nightcap Oak has been known for only three years, therefore little is known of the species population dynamics and demography. While floristic, environmental and ecological data have been collected from a range of sites (Kooyman, 2001) critical questions remain:
- Is the population stable, increasing, or in decline?
- What is the turn over rate for larger stems, smaller stems and seedlings?
- What is the survivorship of seedlings?
- Does the species flower and fruit every year?
- Do fruit crops vary substantially between years?
- How important is the clonal reproductive strategy for the maintenance of the population?
A population monitoring program will be developed to study population dynamics, seedling recruitment, seedling survivorship, flowering and fruiting, habitat attributes, and edaphic, biophysical, and climatic factors.
It is recommended that broad area (whole of population) population structure monitoring be undertaken on a regular (annual to bi-annual) basis to detect any variations in population dynamics and the species response to any disturbance events. In addition to this, demographic studies based on yearly monitoring of permanently marked individuals at a number of locations (three areas minimum) will be developed. Reproductive success of the population will be monitored to ensure that the population remains viable. Tree health will be monitored on a regular basis.
Justification: Population monitoring is essential to understand whether the population is stable, in decline or expanding and to determine the viability of the Nightcap Oak in the wild.
Performance Criterion: A population monitoring program is developed and undertaken on a regular basis.
Recovery Action 2.3. Genetics
Investigate the amount and distribution of genetic variation within the Nightcap Oak using microsatellite analysis.
Justification: By obtaining direct measures of gene flow (ie. through the genetic investigation of parental and seed material) it will be possible to elucidate the breeding system and population dynamics within this species. Simple experimentation can also be designed to assess the correlation between genetic diversity and seedling fitness. All understanding of current levels of genetic diversity will provide important information on the long-term viability of the Nightcap Oak. It is essential to comprehend what the limiting factors (if any) to its breeding success are, and how gene flow contributes to the maintenance of current levels of diversity.
Performance Criterion: Information on genetic diversity and gene flow from the entire species, as well as data on a representative number of ex-situ germinated seedlings is obtained.
Recovery Action 2.4 Pollination biology and breeding system
Studies into the pollination biology and breeding system of the Nightcap Oak will be carried out to determine the reproductive biology of the Nightcap Oak.
Justification: In order to manage populations of the Nightcap Oak in the wild, it is important to have some knowledge of its reproductive biology, particularly given that pollination and self-compatibility are potentially limiting factors in the species ability to reproduce.
Performance criterion: Pollinator(s) of the Nightcap Oak determined and the breeding system is characterised to improve knowledge of its reproductive biology.
Recovery Action 3.1. Ex-situ conservation
Ex situ plants of the Nightcap Oak will be established in appropriate locations (e.g. regional and national botanic gardens or universities). Ex-situ conservation should aim to sample the variation within the population by propagating plants from a range of parent trees. At a minimum, ten trees should be established as part of the general garden display.
It is unlikely that establishment of a seed bank is appropriate given the probable short-viability of the seed, which is typical of large-fruited Proteaceae.
Justification: As the population numbers of the Nightcap Oak are very low in the wild, it is appropriate that ex situ plants are established at suitable institutions to act as an insurance against any catastrophic disturbance to wild plants. In addition, due to the taxonomic and natural history interest of this species, it is appropriate for plants to be established as part of the living display collection in suitable botanic gardens as an educational resource.
Performance Criterion: Ex situ plants are established as appropriate.
Recovery Action 3.2 Seed collection
Seed collection will need to be undertaken for the ex-situ conservation program. Seed needs to be collected from a range of plants to sample any variation that may be present in the population.
Justification: Seed collection from across the population must be undertaken to allow the establishment of plants for a representative ex-situ collection.
Performance Criterion: Seed is collected from a range of the Nightcap Oak plants.