The northern pig-footed bandicoot or yirratji, Chaeropus yirratji, was extinct long before it was described in 2019.
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Australia’s species extinction crisis in numbers: 2019

Monday, 23 December 2019  | 

Species are classified as Extinct (EX) when there is no reasonable doubt that the last individual has died, and Extinct in the Wild (EX(W)) when individuals only survive in cultivation, captivity, or outside their native range. Exactly 100 Australian species are validly listed as EX or EX(W) under Australian federal, state or territory legislation, and/or under the IUCN; 38 plants, 34 mammals,10 invertebrates, 9 birds, 4 frogs, 3 reptiles,1 fish, and 1 protist. The true number of extinctions is likely far higher, due to poor survey effort (especially non-vertebrate animals, plants and fungi) and uncertain taxonomy (undescribed extinct species). There has been a steady rate of known extinctions since 1788, ~4 extinctions per decade.

In Australia, 1892 species or subspecies at risk of extinction are listed as ‘threatened’ under the Environment Protection and Biodiversity Conservation Act: 156 birds, 134 mammals, 63 reptiles, 59 fishes, 41 amphibians, 66 ‘other animals’, and 1373 plants. Of these, 191 plants, 17 birds, 15 frogs, 10 mammals, 10 reptiles, 7 fishes and 30 other animals are Critically Endangered, meaning they have an extremely high risk of extinction—at least 10 birds and 7 mammals are predicted to be extinct within 20 years. The list of threatened species is incomplete and growing.

Major threats are invasive species (82% of species), ecosystem modification (74%), agriculture (57%), human disturbance (38%), and climate change (35%). Well-funded protected areas aid recovery, but 52% of species face threats outside protected areas, so coordination across tenures is vital. It is estimated that Australia needs to invest AUD$1.69 billion/year to recover threatened species. The current level of investment is ~AUD$122 million/year. Australia’s extinction crisis will deepen without further investment and unless the threats driving biodiversity loss are reduced.

Research Entries

Title
Aims
Results
Braby M. F. (2018) Threatened species conservation of invertebrates in Australia: an overview. Austral Entomol. 57, 173-181.
To outline steps in the invertebrate threated species conservation process and highlight areas that are currently inhibiting invertebrate conservation.
Invertebrates are disadvantaged within the EPBC Act, because unlike the IUCN act there is no Data Deficient category. This is problematic because of an estimated 320,500 invertebrate species in Australia, only 98,700 (c. 30%) have been described, and of the species described, a substantial proportion are lacking data related to spatial distributions and geographical range, abundance of populations, and basic ecological knowledge (e.g. critical habitats). Another failing of the EPBC listing framework is that it does not include criteria for species with ‘restricted area of occupancy and under threat’ which is highly relevant to many short range endemic invertebrate species. Only one Action Plan has been prepared for an invertebrate group (butterflys) in the last 16 years, and Recovery plans only exist for a few iconic species (butterflys).
Davies H. F., Mccarthy M. A., Firth R. S. C. et al. (2018) Declining populations in one of the last refuges for threatened mammal species in northern Australia. Austral Ecol. 43, 602-612.
To assess changes in mammal assemblages on Melville Island, including mammal species with major declines across mainland northern Australia.
Overall, trap-success was 62% lower in 2015, than in 2000-2002. Trap success in 2015 decreased for northern brown bandicoots (90%), brush-tailed rabbit-rats (64%), and black-footed tree-rats (63%), compared to 2000-2002. Site-level species richness reduced by 36% and the proportion of sites where no native mammals were trapped doubled from 13% to 26%, from 2000-2002 to 2015. Shrub density was a significant predictor of site-occupancy by the black-footed tree-rat and the brush-tailed rabbit-rat. Feral cat detection was only a significant predictor for brush-tailed rabbit rats. Fire was not a significant predictor for any of the detected native mammal species.
Garnett S. T., Butchart S. H. M., Baker G. B. et al. (2019) Metrics of progress in the understanding and management of threats to Australian birds. Conserv. Biol. 33, 456-468.
To develop and test standardised metrics to assess progress in research or management of threatened taxa, quantify needs for further action and effective threat alleviation, and provide the means to allocate resources to maximize the benefits of threat reduction to threatened taxa.
Across the 238 bird taxa that were threatened or near threatened in the last 25 years, 181 separate threats and 1847 threat-taxon combinations were identified. Of the 1847 threat-taxon combinations, no threat impact reduction was observed in 85% of cases. For 52% of threat-taxon combinations, research is providing strong direction for management, and management is underway for 43% of the combinations. Research needs were high for species with small ranges, mainland birds (compared to birds on islands), and passerines (compared to shorebirds). Research needs were lower for species listed as threatened under the EPBC Act. Invasive species (particularly cats and black rats) was the major threat class, with the highest scores for all need and achievement metrics. Urban development, agriculture, biological resource use, and natural system modification all had moderate scores and pollution and climate change or extreme weather measures high need scores. Overall, the highest density of threatened taxa is in seas of southern Australia, and the highest density of terrestrial threatened taxa are along the northern and eastern Australian coastlines. Few threatened Australian bird taxa have had all threats reduced to a stage where ongoing management is unnecessary, however there have also been some management successes (eradication of rats on islands ect.) and threat reduction has been achieved in over half of all taxa (55%).
Geyle H. M., Woinarski J. C. Z., Baker G. B. et al. (2018) Quantifying extinction risk and forecasting the number of impending Australian bird and mammal extinctions. Pac. Conserv. Biol. 24.
To predict which Australian mammals and birds are most likely to go extinct over the next 20 years, if current management practices continue.
Of the 40 birds and 41 mammals assessed, 58% and 22% respectively, were characterised as 'extinction imminent'. Of the 20 birds with the highest extinction risk, breed only on small islands (<40 km squared), two are from King Island (1098 km squared) and two others (migratory parrots that spend the non-breeding season in mainland Australia) in Tasmania (64519 km squared). The remaining 13 birds that have mainland distributions occur in intensively modified regions of southern Australia. Five of the 20 most at risk mammals occur only on islands (137-5786 km squared), but none of those islands support a highly threatened bird from the top 20. Half of the most at risk mammals occur mostly in central or northern Australia. From the 40 bird and 41 mammal species assessed, ~10 birds and ~7 mammals are estimated to become extinct within the next 20 years.
Ives C. D., Lentini P. E., Threlfall C. G. et al. (2016) Cities are hotspots for threatened species. Glob. Ecol. Biogeogr. 25, 117-126.
To assess the extent of threatened plant and animal species distributions, and thus, the currently under-utilised opportunity for national biodiversity conservation, within Australian cities.
Of the 1643 threatened species assessed (1215 plants and 428 animals) 30% had distributions that intersected with cities. The distribution of eight threatened species (all plants) entirely overlapped with cities. Cities on average held more threatened species per unit area than non-urban areas. 25% of threatened plants and 46% of threatened animals analysed had distributions intersecting cities. Threatened species richness was higher in coastal areas and around the edges of cities. Ten percent of threatened species found in cities had 30% of their distribution in urban areas. Plants were found in fewer cities (mean = 1.95 ± 2.34 SD) than animals (mean = 12.57 ± 16.63 SD), but had a larger percentage of their distribution overlapping with cities (plant mean = 0.16 ± 0.26 SD, animal mean = 0.04 ± 0.08 SD). From 99 cities, 89% held threatened plant species or appropriate habitat and for both threatened plants and animals, cities overlapped with their distributions more so than all other non-urban areas. On average cities contained 32 threatened species. Sydney contained the most threatened species (124), but few large cities contained high diversities of threatened species—only 12% of cities had more than 10 threatened plant species.
Kearney S. G., Adams V. M., Fuller R. A. et al. (2018) Estimating the benefit of well-managed protected areas for threatened species conservation. Oryx 1-9.
To examine the contribution of protected areas and targeted management to alleviating threats on threatened species
Australian threatened species face 11 major threat classes, with invasive and problematic species impacting the greatest proportion of species (82%), followed by natural system modifications and agriculture (56% of species). Well resourced protected areas could remove one or more threats for almost all threaterned species, whereas protected areas that lack resources could only alleviate one or more threats for 76% of species. Protected areas alone cannot remove all threats to threatened species, 52% face threats that require acitons beyond networks of protected areas.This highlights the importance of a landscape scale approach to threat management as many threatened species occur outside protected areas, and half (52%) of Australia’s threatened species face threats requiring concerted efforts across protected and non-protected areas.
Kearney S. G., Carwardine J., Reside A. E. et al. (2019) The threats to Australia’s imperilled species and implications for a national conservation response. Pac. Conserv. Biol. 25.
To "1) compare frequency with which threatening processes are listed under Australia’s threatened species legislation; 2) provide a national-level understanding of which threats are thought to be affecting Australia's threatened taxa; 3) consider current efforts to address the threats to Australian biodiversity, including the national Threatened Species Strategy and 4) provide recommendations for enhancing the planning and governance environment of threat management to improve the conservation of Australian biodioversity."
Of the 1533 EPBC threatened taxa (vertebrates, invertebrates, plants) reviewed, most species were threatened by invasive species (1257, 82%), ecosystem modification (1136, 74%) and agricultural activity (873, 57%). Other threats included human disturbance (38.4%), climate change (34.8%) and overexploitation (27.4%). Invasive species affected 94.1% of vertebrates, 79.5% of plants and 79.2% of invertebrates, and biggest threats by species were rabbits (Oryctolagus cuniculus), Phytophthora cinnamomic and Feral pigs (Sus scrofa). Other invasive species such as feral cats (Felis catus) and red foxes (Vulpes vulpes) have targeted impacts on critical weight range species. Ecosystem modification was most threatening for invertebrates and fish, such as the silver perch (Bidyanus bidyanus, Critically Endangered) which are impacted by damming of important water bodies such as the Murray Darling. Additionally, changes to fire regimes impact many plant species, such as the critically endangered orange dryandra which relays on fire for germination. Agricultural activity has the highest impacts on birds, mammals and invertebrates. Despite expansions of protected areas, many threatened species remain inadequately protected from listed threats.
Lintermans M. (2013) A review of on-ground recovery actions for threatened freshwater fish in Australia. Mar. Freshwater Res. 64, 775-791.
To review the diversity of on-ground recovery actions for threatened freshwater-fish in Australia, and examine patterns and issues that may guide future recovery efforts.
Of the 428 on-ground recovery actions for threatened freshwater fish, most occur in southern and eastern Australia, especially the Murray-Darling. On-ground recovery actions were reported for 54-74 of the listed species. More than 80% of actions had some form of monitoring and 63% of these reported that goals had been partially achieved, even though no threatened freshwater fish have been de-listed and population trajectories are not usually reported. There are no protected areas for freshwater fish and emergency response recovery actions are increasing, while the scale of most actions remains small-scale and site-based.
Melville J., Chaplin K., Hutchinson M. et al. (2019) Taxonomy and conservation of grassland earless dragons: new species and an assessment of the first possible extinction of a reptile on mainland Australia. R. Soc. Open. Sci. 6, 190233.
To provide an assessment of the taxonomy of grassland earless dragon lizards (Agamidae: Tympanocryptis) of southeastern Australia
On the basis of phylogeography (mtDNA), phylogenetics, external morphology, and micro X-ray CT scans, the authors redefine the distributions of two species and name two new species. They highlight that one species, Tympanocryptis pinguicolla, has not been confidentally sighted since 1969, and may therefore be the first reptile extinction recorded on mainland Australia.
Renwick A. R., Robinson C. J., Garnett S. T. et al. (2017) Mapping Indigenous land management for threatened species conservation: An Australian case-study. PLoS One. 12, e0173876.
To investigate the potential management of threatened terrestrial and freshwater species in Australia on Indigenous land, and the importance of this land for threatened species management.
Overall, 51.3% of threatened species habitat ranges occur on Indigenous land, and 74.3% of all threatened species have some part of their modelled range on Indigenous land. Mammals cover the largest area of range on Indigenous land (57.4%), then reptiles (43.3%), birds (42.9%), frogs (23.1%), and fishes (18.1%). Frogs have the highest percentage of species with some range on Indigenous land (85.7%), followed by mammals (82.3%), birds (73.8%), reptiles (68.9%), and fishes (57.5%). Fifty one percent of the range of threatened species occurs on Indigenous land. In areas where Indigenous people have established conservation co-management partnerships, only 4% of threatened species ranges are covered. Thirty two percent of threatened species ranges occur where Indigenous people have negotiated to take part in conservation management. For all species except reptiles, the coastal areas of Indigenous lands held the highest amount of threatened species.
Scheele B. C., Legge S., Armstrong D. P. et al. (2018) How to improve threatened species management: An Australian perspective. J. Environ. Manage. 223, 668-675
To identify factors that lead to ineffective and inefficient management of threatened species
The paper highlights six core areas of threatened species management that require improvement: "1) stakeholder engagement and communication; 2) fostering strong leadership and the development of achievable long-term goals; 3) knowledge of target species' biology and threats, particularly focusing on filling knowledge gaps that impede management, while noting that in many cases there will be a need for conservation management to proceed initially despite knowledge gaps; 4) setting objectives with measurable outcomes; 5) strategic monitoring to evaluate management effectiveness; and 6) greater accountability for species declines and failure to recover species to ensure timely action and guard against complacency."
Scheele B. C., Legge S., Blanchard W. et al. (2019) Continental-scale assessment reveals inadequate monitoring for threatened vertebrates in a megadiverse country. Biol. Conserv. 235, 273-278.
To evaluate the extent to which current monitoring complies with key recommendations for all threatened terrestrial and freshwater vertebrates in Australia. Then using the strengths and weaknesses of monitoring techniques to guide management and prevent species loss.
Of the 408 threatened australian vertebrates (excluding marine mammals and fish), only 74% received some monitoring. The proportion of species monitored was highest among mammals (89%), followed by birds (76%), amphibians (75%), reptiles (62%), and fish (53%). Endangered and critically endangered taxa were more likely to be monitored than vulnerable or other taxa. Monitoring quality was highest for birds, than amphibians, fish, mammals, and reptiles. Also, currently the EPBC act threatened species list does not incorporate the total number of taxa requiring conservation action. Of the 56 fish considered in the review, only 38 were EPBC listed.
Tingley R., Macdonald S. L., Mitchell N. J. et al. (2019) Geographic and taxonomic patterns of extinction risk in Australian squamates. Biol. Conserv. 238.
First comprehensive IUCN assessment of Australian terrestiral squamates
Most species (86.4% of 948 species) were listed as Least Concern, 4.5% as Data Deficient, 7.1% as Threatened (3.0% Vulnerable, 2.7% Endangered, 1.1% Critically Endangered, one species Extinct (Emoia nativitatis), and two Extinct in the Wild (all endemic to Christmas Island). Agriculture, fire and invasive species were most dominant threats among species. The number of threatened species is higher on islands, southern Alps, and northern Australia. One in five threatened species are not present in any protected areas.
Ward M. S., Simmonds J. S., Reside A. E. et al. (2019) Lots of loss with little scrutiny: The attrition of habitat critical for threatened species in Australia. Conserv. Scien. Prac. 1.
To assess how effective the Australian EPBC Act has been at regulating the loss of potential habitat for terrestrial threatened species, terrestrial migratory species, and threatened ecological communities, between 2000 and 2017.
An estimated 7.7 million ha of potential habitat and communities was cleared in Australia between 2000 and 2017. The EPBC Act is the policy which is intended to protect this habitat, but it is not enforced. The lack of enforcement means that most land clearing is not referred to the Federal Government for assessment and therefore 93% of land clearing investigated was not scrutinized under the EPBC Act.
Wintle B. A., Cadenhead N. C. R., Morgain R. A. et al. (2019) Spending to save: What will it cost to halt Australia's extinction crisis? Conserv. Lett.
To estimate the amount of direct expenditure by Australian governments on threatened species recovery aggregated across the Commonwealth, states and territories, and estimate how much Australia should have been spending to prevent further biodiversity loss
The upper limit of expenditure to recover threatened species in Australia, including direct expenditure and other investment, was estimated to be AU$391 million in 2018-19 and AU$766 million in 2017-18. This level of funding is estimated to be about 15% of what is needed to avoid extinctions and recover threatened species. Across all Australian states, territories and commonwealth jurisdictions, around AU$122m/year is allocated towards targeted threatened species recovery, is about US$51,000 per extant EPBC Act listed species per year. Between 2011 and 2016 the U.S. government spent at least US$1.45b/year on direct threatened species conservation and recovery actions, which is about US$903m per threatened species per year. Evidence suggests that spending by the US is sufficient to achieve relatively strong recovery in listed species, e.g. 85% of birds listed in U.S achieve documented stabilisation or recovery. Funding Australian threatened species recovery at $/species rate of funding provided to species recovery in the U.S would result in an approximately 20-fold increase in funding in Australia compared with current expenditure. When accounting for Australia’s disproportionally large invasive species problem, actual cost of recovering threatened species is estimated at AU$1.29b/year. This is less than half the amount of money Australians spent on pet care in 2019.
Woinarski J. C. Z., Braby M. F., Burbidge A. A. et al. (2019) Reading the black book: The number, timing, distribution and causes of listed extinctions in Australia. Biol. Conserv. 239.
To discern the number, timing, distribution and causes of listed extinctions in Australia, with an aim to learn from those losses in order to avert or reduce the likeliness of future losses.
Since Australia's colonisation by Europeans in 1788, 100 Australian endemic species (ten invertebrates, one fish, four frogs, three reptiles, nine birds, 34 mamals, one protist, and 38 plants) have been validly listed as extinct (or extinct in the wild). The EPBC Act only recognises 62 of the 100 extinctions, with 45 listed on the IUCN Act, and 87 listed under state legislation. The first extinction (Porphyrio albus) is thought to have occurred within a decade of European colonisation, with at least one recorded extinction each decade since 1830, at a rate of loss of 4.3 species per decade, with three extinctions and two extinctions in the wild occuring within the last decade. Of the 100 extinct Australian species, 21 were restricted to islands smaller than Tasmania, including 100% of extinct reptiles, 78% of extinct birds, and 18% of extinct mammals. Most extinctions have occured in semi-arid areas or bioregions dominated by islands, with 78 of Australia's 89 bioregions having had at least extinction record. The causes that have contributed most to extinctions include introduced animals (64 extinctions impacting mostly mammals, reptiles, and birds) and habitat loss (62 extinctions impacting mostly plants and invertebrates). Threats varied between taxonomic groups, e.g. clearing was the highest contributor of extinctions for plants and disease for frogs. The sole extinction due at least in part to climate change was in fact the most recent extinction, the Bramble Cay Melomys (Melomys rubicola).
Woinarski J. C. Z., Garnett S. T., Legge S. M. et al. (2017) The contribution of policy, law, management, research, and advocacy failings to the recent extinctions of three Australian vertebrate species. Conserv. Biol. 31, 13-23.
Detail the circumstances of three species extinctions; Christmas Island pipistrelle (Pipistrellus murrayi, CIP), Bramble Cay melomys (Melomys rubicola, BCM), and Christmas Island forest skink (Emoia nativitatis, CIFS), detail key characteristics of the extinctions, identify causal or contributory factors and devise recommendations to reduce the likelihood of similar future failures
There are failings in Australian environmental legislation and policy. Despite both CIP and BCM being listed as endangered in a timely manner, the recovery plans were implemented either too late, or were not threat specific, and neither considered the emergency response of captive breeding. Listing the CIF was severely delayed (15 years) and no recovery plan was implemented. For Christmas Island species, poor biosecurity allowed threats to establish on the island that ultimately contributed to both extinctions. A severe lack of funding to prevent extinction was noted for all three species — multiple attempts at securing government funding for research were rejected — contributing substantially to extinctions. Systematic monitoring programs for CIFS and BCM were absent. An effective monitoring program was established for CIP however data was left unpublished and there were no inbuilt decline thresholds to trigger a conservation response.
Woinarski J. C., Burbidge A. A. & Harrison P. L. (2015) Ongoing unraveling of a continental fauna: decline and extinction of Australian mammals since European settlement. PNAS. 112, 4531-40.
A review of the conservation status of all Australia’s land and marine mammal species and sub-species since European arrival in Australia.
Of Australia’s 273 endemic species of land mammal, almost half are now extinct (30 species, 11%), threatened (56 species, 21%) or near threatened (52 species, 15%). Mammal extinctions in Australia have occurred at roughly two per decade and this rate is continuing. The proportion of threatened or extinct non-endemic species is much lower than for endemic species. Fifty-five terrestrial mammal species have worsened in conservation status since 1992, and Australian mammal extinctions comprise 35% of recent global mammal extinctions. Higher rates of loss have been observed in rodent and marsupial species within the “critical weight range” of 35 g to 5.5 kg, and relatively less loss in bat species. Feral predators are among biggest threats to native terrestrial mammals, along with the loss of Indigenous management, habitat clearing, pastoralism, human exploitation, changed fire regimes, and disease. Marine mammals are influenced mainly by global threats (exploitation, bycatch in fisheries, marine pollution ect.). Substantial declines of marine mammals in Australian waters occurred historically for some exploited species, particularly larger whales, seals, and sea lions.