Extinction is forever – and it is happening all around us

Extinction is forever – and it is happening all around us
7
Dec

Is there anything scarier than the thought of being the last of your species? Many movies have been made about it; lone survivors in a wasteland, struggling to survive. Well, as fantastical as that sounds, it may not be such a farfetched notion as we would like to think. And of course there is the sobering reality in all of our minds that simply states ‘extinction is forever.’

We humans are currently living through what scientists are calling the 6th wave of mass extinction. We know of some of the previous ones, including perhaps the most infamous; the one that wiped out the dinosaurs and led to the eventual rise of mammalian life-forms, including ourselves. But do many of us know that this is happening once more right now across the globe? Many of us have heard the term thrown loosely around in recent years, but do we really know what it means?

To make it a little more tangible, let’s bring the story close to home and look at Australia. Our country is an incredible kaleidoscope of evolutionary history that has led today to the existence of 560,000 species of plants and animals that inhabit many thousands of different ecological communities from luscious rainforests to vast coral cays and from interior baking deserts to mist-clad mountain-tops.

Did you know that over 92% of all of Australia’s plants and over 79% of all our animals are found nowhere else on the planet?

At the turn of the millennium, the Australian Federal Government, under the then newly-formed Environment Protection and Biodiversity Conservation (EBPC) Act, and in partnership with the International Union for the Conservation of Nature (IUCN), began comprehensively assessing the populations of a wide array of critically endangered species in Australia. Sadly the outcome of this has shown that over 1,700 of our unique species are currently threatened with extinction (Australian Government 2010) and even more alarming, since the year 2000, a further 98 species have now become extinct (Australian Government 2016; International Union for the Conservation of Nature 2016).

So now the questions beg to be asked: How did this happen? And how is it still happening? Well let’s take a look at some examples that begin to explain how this concerning situation has come to be in Australia.

Let’s begin in Tasmania where there once lived a unique creature called the Thylacine (Thalyacinus cynocephalus). A type of marsupial ‘wolf’, it inhabited the misty forests and tablelands of this small island state. This animal was a popular subject of many Indigenous rock artworks across Tasmania for thousands of years, and fossil-records show that at one point numbers were relatively high right across Australia and possibly even into Papua New Guinea. However, Thylacines slowly disappeared from mainland Australia due to competition with the introduced Dingo (Canis lupus dingo) and were eventually restricted to Tasmania around 2,000 years ago. When Europeans arrived on the island, and agriculture intensified, news spread widely that this species was a threat to livestock. A bounty of £1 per head was issued by the then Government of Tasmania to cull the Thylacine and in the latter 50 years of the 1800s this approach effectively exterminated the species from the wild. The last living Thylacine died in a zoo in Hobart in 1936.

A different story comes from our island territories. Lord Howe, Christmas, Cocos, Kangaroo and Norfolk islands are examples of the unique hotspots of Australia’s island biodiversity. The majority of native species found on these islands (save for a range of nomadic seabirds) are endemic, meaning that these species occur nowhere else on earth. More importantly these island ecosystems have evolved in the absence of any large land-based carnivorous predators, which has resulted in the evolution of unusual species such as dwarf emus, giant flightless waterbirds, oversized stick-insects, walking bats and giant parrots. Sadly, when Europeans reached these islands they brought with them many of their domesticated animals including rats, pigs and cats which resulted in the demise of so many of these unique species within just a few decades. Of the 98 species that have been declared extinct since 2000, 25 were from our islands.

Some species have become extinct despite their previously having occurred over enormous areas, and in some cases, being relatively common throughout their former ranges. Regionally nomadic birds such as the Paradise Parrot (Psephotellus pulcherrimus), marsupials like the Boodie (Bettongia lesueur subsp. graii), Yallara (Macrotis leucura) and Crescent Nailtail Wallaby (Onychogalea lunata) and wind-dispersed plants such as the Grey Groundsel (Senecio georgianus) once had ranges that extended many thousands of kilometres across several states. In the case of the ground-dwelling marsupials, the introduction of feral cats into Australia led rapidly to their demise as these efficient foreign predators quickly spread into the outback. With the current number of feral cats in this country being estimated at 4 million, and with each individual cat known to kill between 5-30 animals each day, the reality of the impact of just this one introduced species becomes startling (Australian Wildlife Conservancy 2016). For species such as the Grey Groundsel and the Paradise Parrot, large-scale agricultural expansion, resource extraction and land clearing has led to the loss of over 90% of their habitats in inner Australia.

Closer to home in our local patch of South-east Queensland we have extinctions occurring right on our doorstep. Of the 98 species that have disappeared, 6 were once found in our local region. This includes the Paradise Parrot (Psephotellus pulcherrimus), Southern Gastric-brooding Frog (Rheobatrachus silus), Mount Glorious Day Frog (Taudactylus diurnus), Acianthus ledwardii – a ground orchid found only at Burleigh Heads, Darling Downs Hopping-mouse (Notomys mordax) and Eastern Bettong (Bettongia gaimardi subsp. gaimardi). For the two frog species, they have died out as temperatures and atmospheric moisture levels have risen sharply at higher altitudes over the decades leading to the spread of a deadly fungal disease called Chytridiomycosis. This fungus does well in warm conditions attacking the skin pores of amphibians and suffocating them to death. Since 2000 we have officially lost 4 unique Australian frogs, forever. Similarly, and most recently, climate change has been found to be responsible for the extinction of Queensland’s Bramble Cay Melomys (Melomys rubicola). This small mouse-like marsupial was only found on the tiny island of Bramble Cay in the Torres Strait. This year, it became the first animal ever to be officially declared extinct as a direct result of human-induced climate change by the Australian Government. The University of Queensland found that mean sea level on the island had dramatically risen in recent decades at a rate twice that of the global average, and after multiple trips to the island to locate the animal in 2014 and 2015, it was declared extinct.

Unfortunately there are many more species on a rapid track to join this sombre hall of fame. The Mountain Pygmy Possum (Burramys parvus), Night Parrot (Pezoporus occidentalis), Regent Honeyeater (Anthochaera phrygia), Red-finned Blue-eye Fish (Scaturiginichthys vermeilipinnis), Audas Spider-orchid (Caladenia audasii) and Wollemi Pine (Wollemia nobilis) are but a handful of our most beloved, yet most threatened species. From invasive pests to a massive reduction in their habitat, and from climate change to relentless infectious diseases, these plants and animals are declining to dangerously low populations. Indeed, some of them may have already vanished in recent months.

What is clear is that the driving force behind all of these extinctions, is us. But why is this so? What are we doing wrong? Well, no matter how ‘green’ we try to be, the reality is that most of our everyday actions in a developed nation such as Australia, have consequences for the environment. Driving a car to work, eating grain-fed beef, dropping litter, planting the wrong kind of plants in your garden; all have small but accumulating impacts on the environment and our native species.

So what can we do? It all seems so overwhelming! Well what we need to do is change our mindset. Let’s work together to turn the old adage “death by a thousand cuts” on its head and into a positive motto. As much as it is true for all these 98 species, that their deaths have been the result of many interlocking factors caused by humans, saving those we have left can be achieved through “healing by a thousand band aids”. What this means is that for every action we take, we can all spend a few seconds consciously thinking of its ramifications, and decide on a potentially different way of getting what we want but with a lesser impact on the world around us. Each choice, no matter how small, will make a difference.

Let’s celebrate, at every opportunity, what incredible and unique life we have coexisting with us in this remarkable country, and spare thought for those that are no longer here. We need to keep educating our younger generations in ways to lift the social and environmental ethics of our society, and never be afraid to enact positive change and embrace new and better ways of doing things. With this we can begin to shift the quickening decline of so many unique life forms, and safeguard a healthy Australia for all species, including our own.

As sobering as it is to bring this issue to everyone’s attention, awareness is part of the way forward. And as we move into 2017 we look forward to sharing with you some of the many ‘good news’ stories of all of the incredible efforts that are going in to species recovery here in Australia; stories that will inspire all of us to continue to help make a difference.

 


LIST OF SPECIES DECLARED EXTINCT SINCE 2000:

Extinct Animals

Mammals

Banded Hare-wallaby (Lagostrophus fasciatus subsp. albipilis) – 2000

Big-eared Hopping-mouse (Notomys macrotis) – 2016

Blue-grey Mouse (Pseudomys glaucus) – 2016

Boodie (type of Bettong) (Bettongia lesueur subsp. graii) – 2000

Bramble Cay Melomys (Melomys rubicola) – 2016

Broad-cheeked Hopping-mouse (Notomys robustus) – 2016

Broad-faced Potoroo (Potorous platyops) – 2016

Bulldog Rat (Rattus nativitatis) – 2000

Capricorn Rabbit-rat (Conilurus capricornensis) – 2016

Crescent Nailtail Wallaby (Onychogalea lunata) – 2016

Darling Downs Hopping-mouse (Notomys mordax) – 2016

Desert Bandicoot (Perameles eremiana) – 2008

Desert Bettong (Bettongia penicillata) – 2016

Desert Rat Kangaroo (Caloprymnus campestris) – 2016

Eastern Bettong (Bettongia gaimardi subsp. gaimardi) – 2000

Eastern Hare-wallaby (Lagorchestes leporides) – 2016

Gould’s Mouse (Pseudomys gouldii) – 2016

Kulurarri (type of Hare-wallaby) (Lagorchestes asomatus) – 2016

Lesser Stick-nest Rat (Leporillus apicalis) – 2000

Lesser Stick-nest Rat (Leporillus apicalis) – 2016

Long-eared Mouse (Pseudomys auritus) – 2016

Long-tailed Hopping-mouse (Notomys longicaudatus) – 2016

Lord Howe Long-eared Bat (Nyctophilus howensis) – 2000

Maclear’s Rat (Rattus macleari) – 2000

Nullarbor Dwarf Bettong (Bettongia pusilla) – 2016

Percy Island Flying Fox (Pteropus brunneus) – 2008

Pig-footed Bandicoot (Chaeropus ecaudatus) – 2016

Rufous Hare-wallaby (Lagorchestes hirsutus subsp. hirsutus) – 2000

Short-tailed Hopping-mouse (Notomys amplus) – 2016

Tammar Wallaby (Macropus eugenii subsp. eugenii) – 2000

Thylacine (Thalyacinus cynocephalus) – 2000

Toolache Wallaby (Macropus greyi) – 2016

Western Barred Bandicoot (Parameles bougainville subsp. fasciata) – 2000

White-footed Rabbit-rat (Conilurus albipes) – 2016

Yallara (type of Bilby) (Macrotis leucura) – 2016

Birds

Grey-headed Blackbird (Turdus poliocephalus subsp. vinitinctus) – 2000

Kangaroo Island Emu (Dromaius baudinianus) – 2012

King Island Emu (Dromaius minor) – 2012

Lord Howe Boobook Owl (Ninox novaeseelandiae subsp. albaria) – 2000

Lord Howe Grey Fantail (Rhipidura fuliginosa subsp. cervina) – 2000

Lord Howe Island Gerygone (Gerygone insularis) – 2012

Lord Howe Tasman Parakeet (Cyanoramphus novaezelandiae subsp. subflavescens) – 2000

Lord Howe White-throated Pigeon (Columba vitiensis subsp. godmanae) – 2000

Macquarie Island Buff-banded Rail (Gallirallus philippensis subsp. macquariensis) – 2000

Macquarie Island Red-fronted Parakeet (Cyanoramphus novaezelandiae subsp. erythrotis) – 2000

Norfolk Island Kaka (Nestor productus) – 2000

Norfolk Island Long-tailed Triller (Lalage leucopyga subsp. leucopyga) – 2000

Norfolk Island Pigeon (Hemiphaga novaeseelandiae subsp. spadicea) – 2000

Norfolk Island Starling (Aplonis fusca) – 2012

Paradise Parrot (Psephotellus pulcherrimus) – 2014

Robust White-eye (Zosterops strenuus) – 2012

Tasmanian Emu (Dromaius novaehollandiae subsp. diemenensis) – 2000

Western Australian Lewin’s Rail (Lewinia pectoralis subsp. clelandi) – 2000

Western Rufous Bristlebird (Dasyornis broadbenti subsp. litoralis) – 2000

White Swamphen (Porphyrio albus) – 2012

White-chested White-eye (Zosterops albogularis) – 2000

Amphibians

Eungella Gastric-brooding Frog (Rheobatrachus vitellinus) – 2004

Mount Glorious Day Frog (Taudactylus diurnus) – 2004

Sharp-snouted Day Frog (Taudactylus acutirostris) – 2000

Southern Gastric-brooding Frog (Rheobatrachus silus) – 2004

Fish

Pedder Galaxias (Galaxias pedderensis) – 2005

Invertebrates

Lake Pedder Earthworm (Romankenkius pedderensis) – 2000

Extinct Plants

Acacia kingiana – 2000

Acianthus ledwardii – 2000

Amperea xiphoclada var. pedicellata – 2000

Amphibromus whitei – 2000

Bennett’s Seaweed (Vanvoorstia bennettiana) – 2003

Clubmoss Everlasting (Ozothamnus selaginoides) – 2000

Cronin’s Tetratheca (Tetratheca fasciculata) – 2000

Daintree River Banana (Musa fitzalanii) – 2000

Decurrent-leaved Frankenia (Frankenia decurrens) – 2000

Deyeuxia lawrencei – 2000

Didymoglossum exiguum – 2000

Diel’s Wattle (Acacia prismifolia) – 2000

Diuris bracteata – 2000

Drummond’s Lepidium (Lepidium drummondii) – 2000

Esperance Dog-weed (Opercularia acolytantha) – 2000

Euphrasia ruptura – 2000

Grass Fern (Monogramma dareicarpa) – 2000

Grey Groundsel (Senecio georgianus) – 2000

Hidden Coleanthera (Coleanthera virgata) – 2000

Hymenophyllum lobbii – 2000

Hymenophyllum whitei – 2000

Hypsela sessiliflora – 2000

Lemmaphyllum accedens – 2000

Lycopodium volubile – 2000

Maiden’s Bush-pea (Pultenaea maidenii) – 2000

Marsdenia araujacea – 2000

Mt Holland Thomasia (Thomasia gardneri) – 2000

Olearia oliganthema – 2000

Paspalum batianoffii – 2000

Persoonia laxa – 2000

Persoonia prostrata – 2000

Short Spider-orchid (Caladenia brachyscapa) – 2000

Small-flowered Leucopogon (Leucopogon cryptanthus) – 2000

Tmesipteris lanceolata – 2000

Trianthema cypseleoides – 2000

Water Tassel-fern (Huperzia serrata) – 2000


REFERENCES

Australian Government (2010) Australia’s Biodiversity Conservation Strategy 2010-2030. National Biodiversity Strategy Review Task Group convened under the Natural Resource Management Ministerial Council. Available online at: https://www.environment.gov.au/system/files/resources/58321950-f8b6-4ef3-bb68-6f892420d601/files/biodiversity-strategy-2010.pdf (Accessed 7 November 2016)

Australian Government (2016) Species Profile and Threats Database. Available online at: https://www.environment.gov.au/cgi-bin/sprat/public/sprat.pl (Accessed 7 November 2016)

International Union for the Conservation of Nature (2016) IUCN Red List. Available online at: http://www.iucnredlist.org/search (Accessed 7 November 2016)

Australian Wildlife Conservancy (2016) Field Programs – Feral Cat Research. http://www.australianwildlife.org/field-programs/feral-cat-research.aspx (Accessed 7 December 2016)

IMAGE CREDITS

https://upload.wikimedia.org/wikipedia/commons/a/aa/Macropus_greyi_Gould.jpg

https://upload.wikimedia.org/wikipedia/commons/d/d5/Thylacinus.jpg

https://upload.wikimedia.org/wikipedia/commons/c/c9/Dromaius_parvulus.jpg

https://upload.wikimedia.org/wikipedia/commons/5/5c/Lesserbilby.jpg

http://photos1.blogger.com/blogger/6772/1888/400/tasmanian_tiger_wideweb__430x305.jpg

Join our mailing list for up to date news and information