The first Threatened Plant Index (2020)

Learn about the main results of the Threatened Plant Index from the TSX Team:

Threatened Plant Index for Australia 2020 for all sites

Interpreting the index graphs

The index shows the average change in populations compared to a base year. It shows a relative change and not population numbers themselves. The base year of this index is 1995, which gets an index score of one. A score of 1.2 would mean a 20% increase compared to numbers in 1995 on average, while a score of 0.8 would mean a 20% decrease compared to 1995 on average.

The Living Planet Index team has produced a blog which illustrates how the numbers are typically crunched to produce an index. This is the same for the calculation of the Threatened Species Index.

Threatened Species Index for Australian Plants 2020

The 2020 index for threatened plants in Australia shows us that between 1995 and 2017 there was a 72% decrease on average in Australian plant populations across all sites for which we have data.

We can also look at how plants are doing at sites with and without conservation management such as herbivore control, weed/disease management, pest control or translocations. At sites where conservation actions have occurred, threatened plants have decreased on average by about 60%, and by about 45% since 2000 for only those sites where translocations have occurred. At sites where no conservation actions have been undertaken (that we know of), populations have decreased on average by about 80%. The separation of plant sites into sites with and without conservation management is based on information communicated by our data custodians.

The overall index is based upon data for many species and subspecies. The 2020 plant index includes data for 112 threatened plants from over 600 time series. As of 2020, this index does not include data on near-threatened plants. As more data is added these numbers will grow.

Within this, some species have decreased a bit more and others a bit less. The grey cloud around the index trend represents some of the variability in the trends of individual species that make up the overall multi-species index. It is created by randomly sampling species trends from all possible trends in the dataset 100 times, and dropping the 5 trends that are furthest from the average, resulting in a 95% “confidence limit”.

In addition to the Australian index, our web visualisation tool allows you to generate indices for individual Australian states and territories and for a range of species groups, such as orchids or shrubs.

More details on the Australian index and all state and territory indices can be found in our research findings factsheets. This project and the factsheets were developed in collaboration with the Commonwealth Department of the Agriculture, Water and the Environment, and all of our major data contributors, including all state and territory governments.

Threatened Species Index for Plants 2020 findings factsheets:

Australia (PDF, 2.9MB)

Australian Capital Territory (PDF, 1.9MB)

New South Wales (PDF, 2.6MB)

Queensland (PDF, 2.2MB)

South Australia (PDF, 2.5MB)

Tasmania (PDF, 1.8MB)

Victoria (PDF, 2.6MB)

Western Australia (PDF, 2.6MB)

Data sources

The current Threatened Species Index for Australian plants includes data sources from the following institutions/reports:

1. ACT Government (2020). Brindabella Midge orchid monitoring. Australian Capital Territory. Aggregated for National Environmental Science Program Threatened Species Recovery Hub Project 3.1. Generated on 2020-11-16
2. ACT Government (2020). Canberra spider orchid monitoring. Australian Capital Territory. Aggregated for National Environmental Science Program Threatened Species Recovery Hub Project 3.1. Generated on 2020-11-16
3. ACT Government (2020). Ginninderra Peppercress monitoring. Australian Capital Territory. Aggregated for National Environmental Science Program Threatened Species Recovery Hub Project 3.1. Generated on 2020-11-16
4. ACT Government (2020). Small Purple pea monitoring. Australian Capital Territory. Aggregated for National Environmental Science Program Threatened Species Recovery Hub Project 3.1. Generated on 2020-11-16
5. ACT Government (2020). Tarengo Leek orchid monitoring. Australian Capital Territory. Aggregated for National Environmental Science Program Threatened Species Recovery Hub Project 3.1. Generated on 2020-11-16
6. ACT Government (2020). Tuggeranong Lignum monitoring. Australian Capital Territory. Aggregated for National Environmental Science Program Threatened Species Recovery Hub Project 3.1. Generated on 2020-11-16
7. Callen R, Silock J (2020). R. Callen & J. Silcock, unpublished data on Grevillea hodgei. Compiled by Jen Silock. The University of Queensland. Aggregated for National Environmental Science Program Threatened Species Recovery Hub Project 3.1. Generated on 2020-11-16
8. Carter O (2020). Unpublished data on Phebalium daviesii from the Tasmanian threatened flora database. Compiled by Oberon Carter. National Action Plan for Australia’s Imperilled Plants (draft). Aggregated for National Environmental Science Program Threatened Species Recovery Hub Project 3.1. Generated on 2020-11-16
9. Collier P, Garnett R, Carter O, Dick J (2020). Forico and Threatened Plants Tasmania, Wildcare Tasmania Inc. (2016 MOU), see 2017 report at DPIPWE and Forico. Phil Collier. Aggregated for National Environmental Science Program Threatened Species Recovery Hub Project 3.1. Generated on 2020-11-16
10. Collier P, Garnett R, Carter O, Dick J (2020). Forico and Threatened Plants Tasmania, Wildcare Tasmania Inc. (2016 MOU), shared data. Phil Collier. Aggregated for National Environmental Science Program Threatened Species Recovery Hub Project 3.1. Generated on 2020-11-16
11. Collier P, Garnett R, Carter O, Dick J (2020). Owners of Rubicon covenanted property: orchid monitoring data, see annual reports at DPIPWE or TLC. Phil Collier. Aggregated for National Environmental Science Program Threatened Species Recovery Hub Project 3.1. Generated on 2020-11-16
12. Davies R (2020). Superb Groundsel (Senecio megaglossus) adjacent to The Dutchmans Stern Conservation Park in South Australia. Davies, R (2004). The endangered Superb Groundsel (Senecio megaglossus) in and adjacent to The Dutchmans Stern Conservation Park in South Australia. Consultants report to Yorke and Mid-North Region, Department for Environment and Heritage. Aggregated for National Environmental Science Program Threatened Species Recovery Hub Project 3.1. Generated on 2020-11-16
13. Davies R-JP (2020). Monitoring of vulnerable daisy Senecio macrocarpus in Messent Conservation Park, South Australia. Davies R-JP (2009, 2005a, 2005b). The monitoring of the impact of fire and hydrological change on the nationally threatened daisy Senecio macrocarpus in Messent Conservation Park in the Upper South East of South Australia, 1992-2009. Consultants report prepared for South East Region, Department for Environment & Heritage. Aggregated for National Environmental Science Program Threatened Species Recovery Hub Project 3.1. Generated on 2020-11-16
14. Davies R-JP (2020). Population Trends for Threatened Plant Species in Parks and Pastoral Leases in South Australia – Acacia menzelii. Davies, R (2000). Population Trends for Threatened Plant Species in Parks and Pastoral Leases in South Australia. Report prepared for the Department for Environment and Heritage. Aggregated for National Environmental Science Program Threatened Species Recovery Hub Project 3.1. Generated on 2020-11-16
15. Davies R-JP (2020). Population Trends for Threatened Plant Species in Parks and Pastoral Leases in South Australia – Balcanoona Wattle. Davies, R (2000). Population Trends for Threatened Plant Species in Parks and Pastoral Leases in South Australia. Report prepared for the Department for Environment and Heritage. Aggregated for National Environmental Science Program Threatened Species Recovery Hub Project 3.1. Generated on 2020-11-16
16. Davies R-JP (2020). Population Trends for Threatened Plant Species in Parks and Pastoral Leases in South Australia – Birds Nest Wattle. Davies, R (2000). Population Trends for Threatened Plant Species in Parks and Pastoral Leases in South Australia. Report prepared for the Department for Environment and Heritage. Aggregated for National Environmental Science Program Threatened Species Recovery Hub Project 3.1. Generated on 2020-11-16
17. Davies R-JP (2020). Population Trends for Threatened Plant Species in Parks and Pastoral Leases in South Australia – Caladenia gladiolata. Davies, R (2000). Population Trends for Threatened Plant Species in Parks and Pastoral Leases in South Australia. Report prepared for the Department for Environment and Heritage. Aggregated for National Environmental Science Program Threatened Species Recovery Hub Project 3.1. Generated on 2020-11-16
18. Davies R-JP (2020). Population Trends for Threatened Plant Species in Parks and Pastoral Leases in South Australia – Codonocarpus pyramidalis. Davies, R (2000). Population Trends for Threatened Plant Species in Parks and Pastoral Leases in South Australia. Report prepared for the Department for Environment and Heritage. Aggregated for National Environmental Science Program Threatened Species Recovery Hub Project 3.1. Generated on 2020-11-16
19. Davies R-JP (2020). Population Trends for Threatened Plant Species in Parks and Pastoral Leases in South Australia – Pleuropappus phyllocalymmeus. Davies, R (2000). Population Trends for Threatened Plant Species in Parks and Pastoral Leases in South Australia. Report prepared for the Department for Environment and Heritage. Aggregated for National Environmental Science Program Threatened Species Recovery Hub Project 3.1. Generated on 2020-11-16
20. Davies R-JP (2020). Population Trends for Threatened Plant Species in Parks and Pastoral Leases in South Australia – Prasophyllum pallidum. Davies, R (2000). Population Trends for Threatened Plant Species in Parks and Pastoral Leases in South Australia. Report prepared for the Department for Environment and Heritage. Aggregated for National Environmental Science Program Threatened Species Recovery Hub Project 3.1. Generated on 2020-11-16
21. Davies R-JP (2020). Population Trends for Threatened Plant Species in Parks and Pastoral Leases in South Australia – Pterostylis arenicola. Davies, R (2000). Population Trends for Threatened Plant Species in Parks and Pastoral Leases in South Australia. Report prepared for the Department for Environment and Heritage. Aggregated for National Environmental Science Program Threatened Species Recovery Hub Project 3.1. Generated on 2020-11-16
22. Davies R-JP (2020). Population Trends for Threatened Plant Species in Parks and Pastoral Leases in South Australia – Pterostylis cucullata. Davies, R (2000). Population Trends for Threatened Plant Species in Parks and Pastoral Leases in South Australia. Report prepared for the Department for Environment and Heritage. Aggregated for National Environmental Science Program Threatened Species Recovery Hub Project 3.1. Generated on 2020-11-16
23. Davies R-JP (2020). Population Trends for Threatened Plant Species in Parks and Pastoral Leases in South Australia – Resin Wattle. Davies, R (2000). Population Trends for Threatened Plant Species in Parks and Pastoral Leases in South Australia. Report prepared for the Department for Environment and Heritage. Aggregated for National Environmental Science Program Threatened Species Recovery Hub Project 3.1. Generated on 2020-11-16
24. Dickson C (2020). Nationally threatened flora status assessment in the South East of South Australia. Dickson C.R. (2016) Nationally threatened flora status assessment in the South East of South Australia. Report to Department of Environment, Water and Natural Resources, Government of South Australia. NGT Consulting – Nature Glenelg Trust, Mount Gambier, South Australia. Aggregated for National Environmental Science Program Threatened Species Recovery Hub Project 3.1. Generated on 2020-11-16
25. Duncan M (2020). National Recovery Plan for the Bald-tip Beard Orchid Calochilus richiae. Duncan, M. (2010). National Recovery Plan for the Bald-tip Beard Orchid Calochilus richiae. Department of Sustainability and Environment, Melbourne. Aggregated for National Environmental Science Program Threatened Species Recovery Hub Project 3.1. Generated on 2020-11-16
26. Fensham R, Silcock J, Foreman P (2020). Eriocaulon aloefolium Vegetation Census. Compiled by Rod Fensham. The University of Queensland. Aggregated for National Environmental Science Program Threatened Species Recovery Hub Project 3.1. Generated on 2020-11-16
27. Fensham R, Silcock J, Foreman P (2020). Eriocaulon giganticum Vegetation Census. Compiled by Rod Fensham. The University of Queensland. Aggregated for National Environmental Science Program Threatened Species Recovery Hub Project 3.1. Generated on 2020-11-16
28. Grimm W (2020). Genoplesium baueri monitoring Ku-ring-gai Chase NP & Ku-ring-gai Wildflower Garden populations. Wendy Grimm. Aggregated for National Environmental Science Program Threatened Species Recovery Hub Project 3.1. Generated on 2020-11-16
29. N Walsh, J Lynch, O Carter O, J Downe, Threatened Species Scientific Committee (2020). N. Walsh & J. Lynch unpublished data on Spyridium furculentum, and data from published sources. National Action Plan for Australia’s Imperilled Plants (draft) AND Carter O & Downe J (2006). National Recovery Plan for the Forked Spyridium Spyridium species 1. Department of Sustainability and Environment, Melbourne. Available from: http://www.environment.gov.au/biodiversity/threatened/recovery-plans/national-recovery-plan-forked-spyridium-spyridium-species-little-desert. In effect under the EPBC Act from 22-Dec-2006 as Spyridium sp. (Little Desert). AND Threatened Species Scientific Committee (2016). Conservation Advice Spyridium furculentum forked spyridium. Canberra: Department of the Environment and Energy. Available from: http://www.environment.gov.au/biodiversity/threatened/species/pubs/87544-conservation-advice-16122016.pdf. In effect under the EPBC Act from 16-Dec-2016. Aggregated for National Environmental Science Program Threatened Species Recovery Hub Project 3.1. Generated on 2020-11-16
30. Nano C, Nano T, Gibson J, Pavey C (2020). Recovery action implementation for threatened arid acacias. Nano et al. (2008). Recovery action implementation for threatened arid acacias: distribution, monitoring and Indigenous ecological knowledge of A. peuce, A. undoolyana, A. pickardii and A. latzii. Aggregated for National Environmental Science Program Threatened Species Recovery Hub Project 3.1. Generated on 2020-11-16
31. NSW Government (2020). Curly-bark Wattle (Acacia curranii) annual monitoring for NSW DPIE Saving Our Species project. Compiled by Darren Shelly. The State of New South Wales. Aggregated for National Environmental Science Program Threatened Species Recovery Hub Project 3.1. Generated on 2020-11-16
32. NSW Government (2020). Eriocaulon carsonii monitoring on artesian springs at Peery Lake for NSW DPIE Saving Our Species project. Compiled by Darren Shelly. The State of New South Wales. Aggregated for National Environmental Science Program Threatened Species Recovery Hub Project 3.1. Generated on 2020-11-16
33. NSW Government (2020). Grevillea kennedyana monitoring within exclosures in Sturt National Park for NSW DPIE Saving Our Species project. Compiled by Darren Shelly. The State of New South Wales. Aggregated for National Environmental Science Program Threatened Species Recovery Hub Project 3.1. Generated on 2020-11-16
34. NSW Government (2020). Saving Our Species monitoring – Pomaderris cotoneaster, Prasophyllum petilum. Compiled by Rob Armstrong. The State of New South Wales. Aggregated for National Environmental Science Program Threatened Species Recovery Hub Project 3.1. Generated on 2020-11-16
35. NSW Government (2020). Saving Our Species Monitoring – Astrotricha roddii, Isoglossa eranthemoides. Compiled by Jill Smith. The State of New South Wales. Aggregated for National Environmental Science Program Threatened Species Recovery Hub Project 3.1. Generated on 2020-11-16
36. NSW Government (2020). Saving our Species monitoring – Banksia vincentia. Data compiled by David Bain. The State of New South Wales. Aggregated for National Environmental Science Program Threatened Species Recovery Hub Project 3.1. Generated on 2020-11-16
37. NSW Government (2020). Saving Our Species monitoring – Caladenia tessellata. Compiled by Kylie Coutts-McClelland. The State of New South Wales. Aggregated for National Environmental Science Program Threatened Species Recovery Hub Project 3.1. Generated on 2020-11-16
38. NSW Government (2020). Saving Our Species monitoring – Calochilus pulchellus. Compiled by Kylie Coutts-McClelland. The State of New South Wales. Aggregated for National Environmental Science Program Threatened Species Recovery Hub Project 3.1. Generated on 2020-11-16
39. NSW Government (2020). Saving our Species monitoring – Diuris aequalis. Compiled by Laura Canackle. The State of New South Wales. Aggregated for National Environmental Science Program Threatened Species Recovery Hub Project 3.1. Generated on 2020-11-16
40. NSW Government (2020). Saving Our Species monitoring – Diuris ochroma, Pomaderris delicata. Compiled by Keith McDougall. The State of New South Wales. Aggregated for National Environmental Science Program Threatened Species Recovery Hub Project 3.1. Generated on 2020-11-16
41. NSW Government (2020). Saving Our Species monitoring – Diuris ochroma, Pomaderris delicata. Keith McDougall. The State of New South Wales. Aggregated for National Environmental Science Program Threatened Species Recovery Hub Project 3.1. Generated on 2020-11-16
42. NSW Government (2020). Saving Our Species monitoring – Eucalyptus recurva, Grevillea wilkinsonii, Prasophyllum affine, Zieria Adenophora, Zieria buxijugum, Zieria formosa. Compiled by John Briggs. The State of New South Wales. Aggregated for National Environmental Science Program Threatened Species Recovery Hub Project 3.1. Generated on 2020-11-16
43. NSW Government (2020). Saving our Species monitoring – Genoplesium baueri. Data compiled by David Bain. The State of New South Wales. Aggregated for National Environmental Science Program Threatened Species Recovery Hub Project 3.1. Generated on 2020-11-16
44. NSW Government (2020). Saving our Species monitoring – Grevillea obtusiflora. Data compiled by David Coote. The State of New South Wales. Aggregated for National Environmental Science Program Threatened Species Recovery Hub Project 3.1. Generated on 2020-11-16
45. NSW Government (2020). Saving Our Species monitoring – Pterostylis vernalis. Data compiled by David Bain. The State of New South Wales. Aggregated for National Environmental Science Program Threatened Species Recovery Hub Project 3.1. Generated on 2020-11-16
46. NSW Government (2020). Saving our Species monitoring – Wollemia nobilis. Compiled by Tony Auld and Berin Mackenzie. The State of New South Wales. Aggregated for National Environmental Science Program Threatened Species Recovery Hub Project 3.1. Generated on 2020-11-16
47. NSW Government (2020). Xerothamnella parvifolia census monitoring on Mt. Poole for NSW DPIE Saving Our Species project. Compiled by Darren Shelly. The State of New South Wales. Aggregated for National Environmental Science Program Threatened Species Recovery Hub Project 3.1. Generated on 2020-11-16
48. NSW Government (2020). Zieria obcordata population trend monitoring for NSW DPIE Saving Our Species project. Compiled by Darren Shelly. The State of New South Wales. Aggregated for National Environmental Science Program Threatened Species Recovery Hub Project 3.1. Generated on 2020-11-16
49. Reiter NH (2020). N. Reiter, unpublished data on Sphaerolobium acanthos. National Action Plan for Australia’s Imperilled Plants (draft). Aggregated for National Environmental Science Program Threatened Species Recovery Hub Project 3.1. Generated on 2020-11-16
50. Reiter NH, Walsh NG, Lawrie AC (2020). Causes of infertility in the endangered Australian endemic plant Borya mirabilis. Reiter et al. (2015). Causes of infertility in the endangered Australian endemic plant Borya mirabilis (Boryaceae). Australian Journal of Botany 63, 554-565. Aggregated for National Environmental Science Program Threatened Species Recovery Hub Project 3.1. Generated on 2020-11-16
51. Rule K, Molyneux WM (2020). Two new mallee Eucalypts (Myrtaceae) from Gippsland, Victoria. Rule, K. & Molyneux, W.M. (2011). Two new mallee Eucalypts (Myrtaceae) from Gippsland, Victoria. Muelleria 29, 16-26. Aggregated for National Environmental Science Program Threatened Species Recovery Hub Project 3.1. Generated on 2020-11-16
52. SA Government (2020). Acanthocladium dockeri natural sites counting in South Australia. Compiled by Doug Bickerton. The State of South Australia. Aggregated for National Environmental Science Program Threatened Species Recovery Hub Project 3.1. Generated on 2020-11-16
53. SA Government (2020). Northern Lofty Block Threatened Orchid Recovery Team – Caladenia argocalla, C. gladiolata, C. intuta, C. macroclavia, C. woolcockiorum, Pterostylis despectans, P. lepida. The State of South Australia. Aggregated for National Environmental Science Program Threatened Species Recovery Hub Project 3.1. Generated on 2020-11-16
54. SA Government (2020). Project 377: THREATENED ORCHID MONITORING (SE) Prasophyllum frenchii. The State of South Australia. Aggregated for National Environmental Science Program Threatened Species Recovery Hub Project 3.1. Generated on 2020-11-16
55. SA Government (2020). Project 832: IMPACT OF FIRE ON ORCHID POLLINATION-MLR Caladenia behrii, Caladenia rigida. The State of South Australia. Aggregated for National Environmental Science Program Threatened Species Recovery Hub Project 3.1. Generated on 2020-11-16
56. SA Government (2020). SA Murray Darling Basin Threatened Flora Recovery Team dataset. The State of South Australia. Aggregated for National Environmental Science Program Threatened Species Recovery Hub Project 3.1. Generated on 2020-11-16
57. Silock J (2020). J. Silcock unpublished data on Gunniopsis sp. The University of Queensland. Aggregated for National Environmental Science Program Threatened Species Recovery Hub Project 3.1. Generated on 2020-11-16
58. Taylor T (2020). T. Taylor, unpublished data on Gossia gonoclada. National Action Plan for Australia’s Imperilled Plants (draft). Aggregated for National Environmental Science Program Threatened Species Recovery Hub Project 3.1. Generated on 2020-11-16
59. Vic Government (2020). Victorian Biodiversity Atlas data extract – plants. The State of Victoria. Aggregated for National Environmental Science Program Threatened Species Recovery Hub Project 3.1. Generated on 2020-11-16
60. WA Government (2020). DBCA threatened plants monitoring – Midwest, South Coast, Warren and Wheatbelt. Compiled by Colin Yates. The State of Western Australia. Aggregated for National Environmental Science Program Threatened Species Recovery Hub Project 3.1. Generated on 2020-11-16

Three Springs Daviesia (Daviesia bursarioides), an Endangered shrub native to Western Australia. Photo: Andrew Crawford.