Abba Bell (Darwinia sp. Williamson) interim recovery plan 2003-2008

Interim recovery plan no. 139
Gillian Stack & Val English
Department of Conservation and Land Management, Western Australia, 2003


Scientific Name: Darwinia sp Williamson Common Name: Abba Bell
Family: Myrtaceae Flowering Period: October
Dept Region: South West Dept District: Blackwood
Shire: Busselton Recovery Team: South West Region Threatened Flora Recovery Team

Illustrations and/or further information: A. Brown, C. Thomson-Dans and N. Marchant (Eds) (1998) Western Australia's Threatened Flora. Department of Conservation and Land Management, Perth.; V. English (1999) Shrubland Association on Southern Swan Coastal Plain Ironstone, Draft Interim Recovery Plan. Department of Conservation and Land Management, Perth.

Current status: Darwinia sp. Williamson was declared as Rare Flora under the Western Australian Wildlife Conservation Act 1950 in October 1996 and ranked as Critically Endangered (CR) in November 1998. It currently meets World Conservation Union (IUCN, 2000) Red List category 'CR' under criteria A4ce; B1ab(iii)+2ab(iii) and C2a(ii) (IUCN 2000), as it is only known from a single population of less than 250 mature individuals, with continued decline in the quality of the habitat. Darwinia sp. Williamson is also listed as Endangered under the Commonwealth Environmental Protection and Biodiversity Conservation Act 1999 (EPBC Act).

An Interim Recovery Plan was developed for the species in 1999 (Stack et al. 1999). Information accumulated since that plan was completed has been incorporated into this plan and this document now replaces Stack et al. (1999). This IRP will be implemented in conjunction with the IRP for the 'Shrublands on southern Swan Coastal Plain Ironstones' (English 1999) and with IRPs for other CR taxa that occur at the same locality (Brachysema papilio, Lambertia echinata subsp. occidentalis and Petrophile latericola).

Critical habitat: The critical habitat for Darwinia sp. Williamson comprises the area of occupancy of the known wild and translocated populations; similar habitat within 200 metres of wild and translocated populations; corridors of remnant vegetation that link wild and translocated populations; the local catchment area for the surface and groundwaters that supply the wetland habitat; and additional nearby occurrences of similar habitat that do not currently contain the species but may have done so and may be suitable for additional translocations.

Habitat critical to the survival of the species, and important populations Given that this species is listed as Critically Endangered it is considered that all known habitat for wild and translocated populations is critical to its survival

Benefits to other species/ecological communities

Population 1 is located within an occurrence of a Threatened Ecological Community (TEC) listed as Endangered under the EPBC Act, and Critically Endangered in Western Australia. Other listed flora also occur in the wider habitat of Population 1 of Darwinia sp. Williamson (Gastrolobium papilio (previously Brachysema papilio), Lambertia echinata subsp. occidentalis, and Petrophile latericola). Recovery actions implemented to improve the quality or security of the habitat of Darwinia sp. Williamson Population 1 are likely to improve the status of the TEC in which this population is located, and also that of other listed flora that occur in the wider habitat.

International obligations

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 Darwinia sp. Williamson is not listed under any international agreement, the implementation of other international environmental responsibilities is not affected by this plan.

Role and interests of indigenous people

There are no known indigenous communities interested or involved in the management of areas affected by this plan. Therefore no role has been identified for indigenous communities in the recovery of this species.

Social and economic impacts

The implementation of this recovery plan is unlikely to cause significant adverse social and economic impacts. There are mineral leases over the area that contains population 1 of Darwinia sp. Williamson, however, an agreement has been negotiated with the mining company with regard the future management of the area that is to be mined immediately adjacent to the population. Recovery actions refer to continued liaison between stakeholders with regard this area.

Evaluation of the Plans Performance

The Department of Conservation and Land Management, in conjunction with the Recovery Team will evaluate the performance of this IRP. In addition to annual reporting on progress with listed actions and comparison against the criteria for success and failure, the plan is to be reviewed within five years of its implementation.

Habitat requirements: Darwinia sp. Williamson is known from a single wild population (Population 1) at the base of the Whicher Range, and is confined to a highly restricted ironstone habitat. The habitat is a winter-wet area of shrubland over shallow red clay over ironstone. A fire in 1993 resulted in the death of almost all mature individuals, however, 100 seedlings were located at the site in October 1994. Associated species are Hakea varia, Loxocarya magna and Chamelaucium roycei. The plant association in which the species occurs is the Critically Endangered Threatened Ecological Community (TEC) 'Shrublands on southern Swan Coastal Plain Ironstones' (English 1999). There are six priority species and six additional Declared Rare Flora (DRF) species in the ironstone community in the vicinity of Darwinia sp. Williamson. Three of these DRF are also ranked Critically Endangered.

Existing Recovery Actions: The following recovery actions have been or are currently being implemented:

  1. All appropriate land managers have been notified of the presence and threatened status of the species.
  2. Four areas that contain the ironstone habitat have been purchased as conservation reserves.
  3. Seed has been collected from Population 1 on three occasions, and is stored in the Department's Threatened Flora Seed Centre at -18°C.
  4. The Botanic Garden and Parks Authority currently have eleven plants of Darwinia sp. Williamson from three clones.
  5. An experimental translocation has been implemented in stages in 2001 and 2002, with planting occurring into two recently acquired reserves. Actions implemented in association with the translocations include treatment of translocates with phosphite, weed and rabbit control, and fencing to prevent grazing.
  6. In 1997, samples were taken by staff of the Department's Science Division which positively identified the presence of the plant pathogen Phytophthora cinnamomi (dieback) in the habitat.
  7. The site of the wild Darwinia sp. Williamson population has been sprayed with phosphite a number of times to combat dieback disease. Spraying and monitoring of the effects of treatment are ongoing. Disease hygiene procedures are implemented during all operations.
  8. A fire response plan has been developed, and is being implemented.
  9. An information sheet about the TEC habitat of the species has been produced by the local catchment group in liaison with the Department.
  10. Implementation of the recovery actions outlined in the IRP for the TEC ‘Shrublands on southern Swan Coastal Plain Ironstones’ (English 1999) has commenced and is ongoing. Various actions that protect the community in which it occurs also protect this taxon.
  11. An information sheet that describes and illustrates the taxon, threats to it and recovery actions has been produced.
  12. Blackwood District staff have developed a map that defines areas not available for commercial wildflower picking to help prevent accidental damage or spread of disease to the population.
  13. Staff from the Department's Blackwood District regularly monitor wild and translocated populations of the species.
  14. The South West Region Threatened Flora Recovery Team is overseeing the implementation of this IRP and will include information on progress in an annual report to the Department's Corporate Executive and funding bodies.

IRP Objective: The objective of this Interim 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.

Recovery criteria

Criteria for success: The number of individuals within populations and/or the number of populations have increased by ten percent or more.
Criteria for failure: The number of individuals within populations and/or the number of populations have decreased by ten percent or more.

Recovery actions

  1. Coordinate recovery actions
  2. Maintain disease hygiene
  3. Continue Phytophthora control
  4. Map critical habitat
  5. Implement the fire management strategy
  6. Continue the translocation process
  7. Liaise with land managers
  8. Monitor populations
  9. Continue weed control
  10. Control grazing
  11. Conduct further surveys
  12. Collect seed and cutting material
  13. Obtain biological and ecological information
  14. Stimulate the germination of soil-stored seed
  15. Promote awareness
  16. Review the need for a full recovery plan