A recent Federal Court decision setting aside approval of the Carmichael coal mine in Queensland has sparked debate about whether courts should have that kind of power.

The claim: Greens Leader Richard Di Natale says Australia has "one of the highest loss of species anywhere in the world".

Greens Leader Richard Di Natale says Australia has "one of the highest loss of species anywhere in the world". The verdict: When comparing places on the IUCN Red List, Australia is in the top five for extinction of animals and plant species, and the top 10 for endangered and threatened species. Senator Di Natale's claim is correct.

The project was sidelined because the Federal Government had not properly considered environmental advice around two vulnerable species in the area.

Greens leader Richard Di Natale says it is important that endangered species be considered by the courts because Australia has "one of the highest loss of species anywhere in the world".

ABC Fact Check investigates.

Australia's biodiversity

Australia has one of the most diverse collections of plants and animals in the world.

"We have more species of higher (vascular) plants than 94 per cent of countries on Earth, and more non-fish vertebrate animals (mammals, birds, reptiles and amphibians) than 95 per cent of the world's countries," environmental advocacy group the Wilderness Society's summary of Australia's biodiversity says.

"We have more species of mammals than 93 per cent of countries, more birds than 79 per cent of countries, more amphibians than 95 per cent of countries, and more reptiles than any other country on Earth."

The continent is home to more than one million known species of plants and animals, with many endemic (unique) to Australia.

"About 85 per cent of flowering plants, 84 per cent of mammals, more than 45 per cent of birds, and 89 per cent of inshore, freshwater fish are endemic," the federal Department of the Environment's website says.

What is extinction?

Surveys to determine whether the Tasmanian tiger (Thylacine) was extinct or not began in the 1930s.

For a species to be considered extinct there is a set criteria it must meet. That criteria can differ between states and countries, which means that state, national and international extinction lists do not always match up.

Australia's Threatened Species Commissioner Gregory Andrews told Fact Check that the federal and state governments are working towards a unified criteria based on the International Union for Conservation of Nature (IUCN) Red List's criteria.

He said: "Assessors only declare a species extinct when it hasn't been detected, despite appropriate and extensive surveys and beyond reasonable doubt, for a length of time relevant to its lifespan (longer timeframes for longer-lived species)."

How many species are extinct?

The Australian Government keeps track of endangered and extinct species through the Environment Protection and Biodiversity Conservation (EPBC) Act list.

According to the EPBC Act list of threatened fauna 54 mammals, birds, frogs and other animals are extinct, and one fish is extinct in the wild.

The brush-tailed bettong is on the EPBC list as extinct. ( Supplied: Australian Wildlife Conservancy )

The corresponding list for flora (plant species) lists 39 extinct species.

Mr Andrews told Fact Check that Australia has the highest loss of mammal species anywhere in the world.

"35 per cent of all global mammal extinctions since 1500 have been Australian (30 out of 84 world-wide extinctions).

"Australia has lost 29 mammals since European colonisation, and feral predators are implicated in 28 of these extinctions. This compares to the loss of only one mammal in North America – the Sea Mink," he said.

Mr Andrews said Australia's mammal losses "are especially significant given our terrestrial mammal fauna is extremely unique".

Terrestrial mammals are those that live predominantly, or solely, on land.

"Almost 90 per cent of terrestrial species are found only in Australia," Mr Andrews said.

John Woinarski, a professor of conservation biology at Charles Darwin University in the Northern Territory, told Fact Check that Australia has lost more mammal and plant species over the past 200 years than any other country.

Sorry, this video has expired Watch John Barron present the facts

In a paper published in April 2015, Professor Woinarski and colleagues Andrew A. Burbidge and Peter L. Harrison write: "The 29 Australian endemic mammal extinctions comprise 35 per cent of the world's modern mammal extinctions. Some 1.5 per cent of the world's 5,500 mammal species are extinct, a proportion substantially less than for Australia."

The paper says of the 273 Australian endemic land mammal species, 11 per cent are extinct.

It also says 2.1 per cent of native but non-endemic land mammal species were extinct in Australia.

How do we compare?

Mr Andrews told Fact Check that a fair way to compare Australia's extinction rate with other nations is to look at the International Union for Conservation of Nature and Natural Resources (IUCN) Red List.

The Red List was first set up in 1964 and is maintained year-round and updated regularly, most recently in June 2015.

Mr Andrews said that while the Red List does not tally exactly with Australian lists, "given its consistency of measurement across countries, the IUCN's data is best for international comparisons".

"According to the IUCN, only three countries have lost more animal species than Australia. Australia is fourth (behind USA, Mauritius, French Polynesia) across about 250 countries," he said.

Professor Woinarski also recommended the Red List as a point of reference.

The most recent version of the Red List shows that only four places have more extinct and extinct in the wild species (plant and animal) than Australia.

Extinct species USA 266 French Polynesia 89 Mauritius 46 Saint Helena, Ascension and Tristan da Cunha 36 Australia 35 Source: IUCN Red List tables 6a & 6b

The Red List does not count territories of nations as part of the one entity. So Australia's listing does not include Christmas, Norfolk or Cocos (Keeling) islands. When added, these areas boost Australia's extinct species to 46.

But the list also does not include, for example, the French overseas territory French Polynesia as part of France.

Most places on the lists have fewer than 10 extinct species listed. Other countries with more than that include Mexico with 31, New Zealand on 28, and Sri Lanka on 21.

Australia is also in the top 10 for endangered and threatened species with 909 species categorised as critically endangered, endangered or vulnerable. Across Australia, Christmas, Norfolk and Cocos (Keeling) islands the total is 1018.

The country with the most endangered species - almost double the second highest, Malaysia on 1252 - is Ecuador, with 2308.

Why don't the lists match?

In a public lecture in September 2013 Stephen Garnett, professor of conservation and sustainable livelihoods at Charles Darwin University, said that there were many reasons why the Australian and IUCN extinction and endangered lists do not tally.

"There are three reasons for the discrepancies between the two lists. The first is that the government could be legitimately reluctant to change the EPBC list because of legislative implications, and require a higher level of proof of threat than the IUCN Red List, which can afford to be more precautionary," he said.

The ornamental snake (Denisonia maculata) is on the EPBC list as vulnerable. It is one of two animals that were the cause of a court decision to overturn a mine approval in Queensland. ( Wikimedia: Stewart Macdonald )

Professor Garnett said a lack of resources in Australia to monitor the list was the second reason.

"Between 2000 and 2011 there were just 27 changes in status for Australian birds compared with more than double that number for the IUCN Red List (56)," he said.

"The third reason flows from the second. Almost 85 per cent of all taxa listed under the EPBC Act have been carried over from the previous Act and so never tested against the criteria of the EPBC Act... Thus, assessments of status can date back 25 years without adjustment up or down despite new knowledge, new criteria, sometimes even new taxonomy as well as genuine changes in status."

What drives species loss?

Professor Woinarski and his colleagues write that "much of the current biodiversity decline is occurring in areas subject to the most rapid human population growth and highest rate of habitat loss and transformation, and in countries whose limited economies constrain the allocation of resources to biodiversity conservation".

Australia however does not fit that criteria.

"On these criteria, Australia should have relatively few conservation concerns: its population density is extremely low by global standards, most of the continent remains very sparsely settled and little modified, and the Australian nation is relatively affluent: indeed, most of the continent comprises one of the world's few remaining large areas of largely natural environments," they said.

Leadbeater's possum is on the EPBC critically endangered list. ( AAP: Healesville Sanctuary )

What's more, the scientific community does not know for sure what is causing these extinctions.

"Some of the causes of the post-1788 Australian mammal losses remain unresolved, baffling, and contested. This is so for even the most recent of the mammal extinctions," they wrote.

They said feral animals and invasive species were a major problem.

Mr Andrews said there were many reasons for Australia's extinction rates.

The verdict

When comparing places on the Red List, Australia is in the top five for extinction of animal and plant species, and the top 10 for endangered and threatened species.

Even more species are listed as extinct on the Australian EPBC Act list than on the Red List, and experts agree Australia is experiencing high rates of species loss.

Senator Di Natale's claim that Australia has "one of the highest loss of species anywhere in the world" is correct.

Sources