Habitat critical to the survival of a species is habitat identified as being critical to the survival of a listed threatened species or listed threatened ecological community. The area of occupancy of the currently known Banksia ionthocarpa subsp. ionthocarpa population has been mapped. However the total area of habitat critical to its survival has not yet been mapped and this is included as an action under this Recovery Plan.
The habitat critical for survival of Banksia ionthocarpa subsp. ionthocarpa comprises:
the area of occupancy of the known population;
areas of similar habitat within 200 metres of the known population that provides potential habitat for natural recruitment;
remnant vegetation that surrounds and links subpopulations (this is necessary to allow pollinators to move between subpopulations) and
additional occurrences of similar habitat that do not currently contain the subspecies but may have done so in the past (these represent possible translocation sites).
The species Banksia ionthocarpa is listed as Endangered under the EPBC Act and it is therefore considered that all known habitat for this species and its subspecies is habitat critical to its survival and all populations including translocated populations, are considered important populations. Recovery actions include survey for further populations that would lead to the identification of additional critical habitat.
Benefits to other species/ecological communities The two reserves in which the subspecies occurs have high conservation value as they provide habitat for a number of other threatened and Priority flora taxa, including Orthrosanthus muelleri (DRF), Stylidium diplectroglossum (P1), Verticordia huegelii var. tridens (P1), Chorizemacarinatum (P3), Hakea lasiocarpha (P3), Acrotriche parviflora (P3), Eucalyptus goniantha subsp. goniantha (P4), Pleurophascum occidentale (P4), and several flora species at the limits of their range (Atkins 2009).
This plan is fully consistent with the aims and recommendations of the Convention on Biological Diversity, ratified by Australia in June 1993, and will assist in implementing Australia’s responsibilities under that Convention. However, as Banksia ionthocarpa subsp. ionthocarpais not listed under any international agreement, the implementation of other international environmental responsibilities is not affected by this plan.
One subpopulation occurs in a Class C recreation reserve while the other subpopulation occurs in an adjacent unvested Class C reserve. Their protection may potentially impact on Shire operations.
Role and interests of indigenous people
According to the Department of Indigenous Affairs Aboriginal Heritage Sites Register, Banksia ionthocarpa subsp. ionthocarpaSubpopulation 1A occurs on the registered site Kamballup Pool and Subpopulation 1b and Population 7T occur within two kilometres of at least one of the registered sites Kamballup Pool, Kamballup Bridge, Kalgan Downs and Arizona Pool. The Department has welcomed all consultation seeking input and involvement from Indigenous groups that have an active interest in the areas that are habitat for B. ionthocarpa subsp. ionthocarpa. Indigenous involvement is included as a recovery action.
Social and economic impacts
As the subspecies is located on Shire reserves, the implementation of this IRP has the potential to have some minimal impact. However, the Shire of Plantagenet and DEC are currently considering combining the two reserves into one Nature Reserve (D. Coffey, personal communication). Recovery actions refer to continued negotiations between stakeholders with regard to these areas.
Guide for decision-makers
Section 1 provides details of current and possible future threats. Developments in the immediate vicinity of the single known population or within the defined critical habitat of Banksia ionthocarpa subsp. ionthocarparequire assessment to determine their level of impact. No developments should be approved unless the proponents can demonstrate that they will not have a detrimental impact on the species, or its habitat or potential habitat, or the local surface and ground water hydrology.
DEC, in conjunction with the Albany District Threatened Flora Recovery Team will evaluate the performance of this recovery plan. In addition to annual reporting on progress against the criteria for success and failure, the plan is to be reviewed within five years of its implementation. Any changes to management and/or recovery actions made in response to monitoring results will be documented accordingly.
2. RECOVERY OBJECTIVE AND CRITERIA
The objective of this Recovery Plan is to abate identified threats and maintain or enhance in situ populations to ensure the long-term preservation of the species in the wild.
Criteria for success: The total number of mature individuals within the natural population remains stable or decreases by no more than 10% during the five year period of the plan.
Criteria for failure: The number of mature individuals within the natural population decreases by more than 10% during the five year period of the plan.
3. RECOVERY ACTIONS
Existing or completed recovery actions
All land managers have been notified of the location and threatened status of Banksia ionthocarpa subsp. ionthocarpa. The notification details the Declared Rare and EPBC status the subspeciesand the legal responsibilities to protect it.
Staff from DEC’s Albany District regularly monitor the population.
Preservation of germplasm is essential to guard against the possible extinction of the wild population and may be used to propagate plants for translocations. Staff from DEC’s Threatened Flora Seed Centre (TFSC) have made eleven Banksia ionthocarpa subsp. ionthocarpaseed collections since 1990 with approximately five thousand seeds collected in total. The seed is stored at –18 degrees Celsius and requires no special treatment to achieve germination (3A. Crawford, personal communication). Seeds have been successfully germinated and the resulting seedlings grown and maintained in the Botanic Gardens and Parks Authority (BGPA) nursery. There were 283 Banksiaionthocarpasubsp. ionthocarpaseedlings translocated into the wild in 1999 and 2000 and 88plants currently housed at the BGPA nursery are intended for translocation in winter 2005 (4A. Shade, personal communication)
As discussed in Section 1, Leonie Monks conducted a masters study on three Banksia species including Banksia ionthocarpa subsp. ionthocarpa ms. The study looked at the species’ demography, fire ecology, granivory and drought-stress and included a number of small translocations. DEC staff have investigated factors affecting seedling recruitment and survival (Barrett and Cochrane 2004) (also discussed in Section 1). This included research into the soil seed bank, canopy seed bank, seed longevity, ex situ conservation, germination requirements and the role of disturbance (fire and smoke water application) in stimulating germination of the soil-stored seed reserve.
Firebreaks are maintained around the reserve by DEC (5G. Broomhall, personal communication).
Samples of Banksia ionthocarpa subsp. ionthocarpa were tested for Phytophthora cinnamomi in 1994 and 2001. All samples produced a negative result. However, to help maintain disease-free status, barriers have been put in place on the entry track into Population 1, to restrict access at times of dry soil conditions, and thereby reduce the risk of Phytophthora spread.
A shelter bed was planted around subpopulation 1A to inhibit weed invasion from the adjoining paddock. The area was initially sprayed with Roundup in preparation. Three rows were planted with Eucalyptus vegrandis subsp. recondita, E. uncinata and E. incrassata seedlings. Survival of the outer two rows of eucalypts was poor and the rows were consequently replanted with E. pleurocarpa seedlings. The shelter bed has been slow to establish (S. Barrett, personal communication). Additional seed was collected from Eucalyptus, Allocasuarina and Melaleuca species in November 2004. The seed has been germinated and will be ready for planting along the shelter bed in autumn 2005 (6A. Cochrane, personal communication).
Information regarding Banksia ionthocarpa subsp. ionthocarpa has been disseminated by DEC to the public and scientific community through the production of an information sheet that includes the plant’s description, status and habitat, research projects in progress and photos.
In August 1996 Leonie Monks commenced the translocation of Banksia ionthocarpa subsp. ionthocarpa to eight different study sites. The aim was to investigate whether the species would establish in different soil types or other areas with similar soil. Two of the translocation sites were within the known population (Population 1); two were in dark brown heavy clay soil, lower down the slope; two were on light coloured sandy loam soil, within the Kamballup Reserve; and the final two were on spongolite soil in Kalgan Plains Nature Reserve.
The plants were germinated from seed obtained from both known subpopulations and planted in sites within the same general area but under different land tenures. Herbivores were excluded from the sites using shade cloth and monitoring focused on initial survival, survival over the first summer and growth (height). It was determined that suitable habitat and the correct soil type must be combined for good survival. Seedlings had better survival in spongolite soils, however where the habitat (i.e. vegetation surrounding the population) was not suitable, the survival rate was significantly lower. Monks (1999) considered ongoing monitoring (until flowering, fruiting and seedling recruitment) is imperative.
Monks (1999) found Banksia ionthocarpa subsp. ionthocarpa to have the greatest percentage survival at one site in the Kalgan Plains Nature Reserve. The reserve is approximately 6.5 km from the natural population and has a similar vegetation structure and the same soil type. However, the population did not establish successfully long-term and by 2002 its condition was poor with only 58 of the 283 juveniles surviving. In 2004, 44 of the plants translocated in 1999 were surviving and only 2 of those planted in 2000 were surviving. Watering may have been inadequate over the first summer (1999). A further 566 plants were translocated to Kalgan Plains in winter 2005. All plants are watered and caged (L. Monks, personal communication).
Future recovery actions
Where populations occur on lands other than those managed by DEC, permission has been or will be sought from appropriate land managers prior to recovery actions being undertaken. The following recovery actions are roughly in order of descending priority; however this should not constrain addressing any of the priorities if funding is available and other opportunities arise.