By Dr Pat Pepper

NCWQ Environment Adviser


Danger of anthropogenic mass extinction of species:  In the past the earth has suffered mass extinctions of species:- Ordovician–Silurian extinction events 450–440 Ma (million years ago); Late Devonian extinction: 375–360 Ma Permian–Triassic extinction event 252 Ma Triassic-Jurassic, c 200 Ma; Cretaceous–Paleogene extinction event, c 66 Ma.  Many species could not adapt when the environment changed so rapidly.  Various causes have been proposed:- changes in sea level; lack of oxygen in the ocean triggered by global cooling or oceanic volcanism; flood basalt lava events and  inhibited photosynthesis caused food chains to collapse both on land and at sea from massive land volcanic eruptions; sustained warming.

However, while extinctions, even mass extinctions, are not unprecedented, mankind is now being warned that anthropogenic impacts as such as habitat loss and modification, the spread of invasive species and climate change could well be precipitating another mass extinction.

In a study published in the peer-reviewed journal Proceedings of the National Academy of Sciences, scientists from Stanford and Mexico University, Ceballos, Ehrlich and Dirzo found in a sample of 27,600 land-based mammal, bird, amphibian and reptile species that 32% had decreased in population size and range.  A more detailed analysis of 177 mammal species between 1900 and 2015 found all had lost 30% or more of their geographic ranges and more than 40% of the species had experienced severe population declines.  The problem was not confined to a few high-profile species but also affected populations of many more common species Ceballos G, García A, Ehrlich PR and  Dirzo R, (2017) Biological annihilation via the ongoing sixth mass extinction signaled by vertebrate population losses and 1704949114;   This annihilation was attributed to three major factors; population growth of the human race and how that population is fed, climate change and poaching.

https:// extinction-what-can-we-do-to-stop-it/ 


Australia has the fourth-highest level of animal species extinction in the world.  The latest update of the Red List of Threatened Species published recently by the International Union for Conservation of Nature has the number of extinct animal species in Australia at 40, with 106 also listed as critically endangered.  Australia’s unique reptiles are considered particularly vulnerable, with 7% threatened with extinction.

As one of the world’s 17 megadiverse countries, with 10% of global biodiversity, Australia has the second highest rate of biodiversity deterioration.  The most significant pressures on biodiversity are from land clearing and habitat fragmentation and deterioration, invasive species, climate change, fire regimes and altered hydrology.  Unfortunately, many of these are worsening over time Cresswell ID & Murphy HT (2017). Australia state of the environment 2016: biodiversity, independent report to the Australian Government Minister for the Environment and Energy, Australian Government Department of the Environment and Energy, CanberraThe rate of land clearing in Queensland is of particular concern with over 10% of its tree cover lost between 2010/11 and 2014/15 ABS (2017), Land Account: Queensland, Experimental Estimates 2011-2016, Australian Bureau of Statistics, Canberra,

While the National State of the Environment 2016 report provided a good qualitative sense of the pressures and challenges facing Australia’s ecosystems and species, quantitative conclusions were limited by the lack of long-term, national-scale data sets.  Plans to develop a national biodiversity monitoring and reporting system in the 2010 National Biodiversity Conservation Strategy were not implemented.  Other national-level initiatives, such as the River Health Program and the Wetlands Inventory, were discontinued.

As the authors of the State of the Environment 2016: Biodiversity say The lack of effective monitoring and reporting has been raised in every jurisdictional report, and multiple other reports and papers as a major impediment to understanding the state and trends of Australian biodiversity” Cresswell ID & Murphy HT (2017). Australia state of the environment 2016: biodiversity, independent report to the Australian Government Minister for the Environment and Energy, Australian Government Department of the Environment and Energy, Canberra   Biodiversity monitoring in Australia is limited and often sub-optimal.  Depending on the taxonomic group, 21–46% of threatened vertebrates, and 70% of threatened ecological communities, are not monitored at all.  For threatened animal species, monitoring quality is highly variable: monitoring was most adequate for threatened frogs and birds, followed by mammals, then fish, with reptiles a distant last.  Without monitoring, changes in population and when management intervention is needed cannot be determined.


If good policy which will conserve threatened species, is to be developed good data over time is needed. The Threatened Species Recovery Hub advocates national monitoring programmes that are 1) fit-for-purpose; 2) take place across sites that represent the threatened entity’s distributional and environmental range; 3) occur with appropriate periodicity; 4) run for time periods that are long enough to detect trends; 5) are designed with sufficient statistical power for detecting change; 6) are coordinated across jurisdictions/organisations/ stakeholders; 7) produce monitoring data that is publicly available and regularly reported. In addition, monitoring should be 8) clearly linked to management, and monitoring may be better interpreted when 9) information on demography/life history is collected as well as abundance/distribution data. .  01 May 2018


The Commonwealth government’s 2015 Threatened Species Strategy does have annual specific action plans focused on priorities.  The first such plan, for 2015/16, identified four key action areas: tackling feral cats, providing safe havens for species most at risk, improving habitat and undertaking emergency intervention to avert extinctions.  Each action area identified specific measurable targets.  Lists of 20 priority mammals, 10 priority birds and 27 threatened plant species were developed, with each having at least one project under way to contribute to their recovery (DEE (2016), Reef 2050 Plan: Update on Progress, Australian Government and Queensland Government,   OECD (2019), OECD Environmental Performance Reviews: Australia 2019, OECD Environmental Performance Reviews, OECD Publishing, Paris,


However, the State of the Environment 2016 Report noted that 1,907 species and ecological communities were listed as threatened under national law.  The list includes little known insects, frogs, fish and plants, through to iconic species such as the Koala, Cassowary and Leadbeater’s Possum.  Threatened ecological communities include grasslands, banksia woodlands, rainforest and alpine wetlands.  Invasive species, bushfires, disease and climate change all imperilled the threatened wildlife and ecosystems but the destruction and loss of habitat was the primary cause.



Number of plant species listed under the Environment Protection and Biodiversity Conservation Act 1999, 2011 and 2015 Source: Species Profile and Threats Database, Australian Government Department of the Environment and Energy

Numbers of plant species and critically endangered plant species listed under the Environment  Protection and Biodiversity Conservation Act 1999 in each Interim Biogeographic Regionalisation for Australia region Source: Environmental Resources Information Network, Australian Government Department of the Environment and Energy, 2016


Despite 1907 species and ecological communities being listed as threatened Australia’s national critical habitat register lists only five places as critical habitat with the most recent critical habitat listing in 2005.

Register of Critical Habitat

The Australian Conservation Foundation undertook analysis of existing recovery plans for animals listed as critically endangered and endangered under the EPBC Act.  Out of 230 listed species it was identified that 127 (55%) had recovery plans and 105 (45%) had clearly identified critical habitat that was essential to their survival.  Of the species surveyed, 25 (10%) had identified critical habitat wholly or partly located on Commonwealth land.  Despite this, only two had habitat listed on the national critical habitat register, Australia’s Extinction Crisis Protecting Critical Habitat. 190_ACF_2018_critical_habitat_report_AW.pdf


The OECD Report suggested Australia could follow New Zealand’s lead to obtain robust national and regional biodiversity data.  New Zealand adopted a three-tiered approach to monitoring, designed in consultation with scientists and local councils and led by the Department of Conservation.  Tier 1 monitoring comprises a nationally consistent, systematic biodiversity monitoring programme based on an 8 km national grid.  Tier 2 monitoring is undertaken to assess the effectiveness of management interventions on species and ecosystems.  Biodiversity monitoring protocols are followed to ensure consistency in sample design using a master sample, indicator selection, measures and methods across the country. Tier 3 monitoring involves intensive research into ecosystem dynamics, methods and tools to improve understanding and inform policy and management. OECD (2019), OECD Environmental Performance Reviews: Australia 2019, OECD Environmental Performance Reviews, OECD Publishing, Paris,

Clearly if effective strategies are to be implemented to save Australia’s biodiversity, national  monitoring programmes are needed to run over a species’ distributional and environmental range and for time periods long enough to detect trends.  Sampling needs to be sufficient to give confidence in the results which need to be available in a timely manner for effective recovery plans to be implemented.

Perhaps the efforts of voluntary citizen-scientists as demonstrated by the dedicated bird watchers could be coordinated and extended to other taxa.  As improved tools and technical advances (e.g. satellite telemetry; remote cameras and audio devices) become more available hopefully the situation will improve.


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