7% of Australia's reptiles face extinction

[Flaviemys purvisi]

NOEL KIRKPATRICK
July 10, 2018

Populations of the grassland earless dragon (Tympanocryptis pinguicolla) have been declining, mostly because of feral cats. (Photo: John Wombey/CSIRO/WIkimedia Commons)


The International Union for Conservation of Nature (IUCN) released its latest update to the Red List, a rundown of threatened species around the globe, and a look at one particular continent is eye-opening: Almost all of Australia's reptiles are on the list.

The Red List now includes 975 Australian reptiles, which is nearly every species on the continent. The majority of them are endemic to the continent. Seven percent of the species face extinction if action isn't taken.

"Understanding the threats to each of Australia's native reptile species will help us effectively work with the Australian government, local conservation groups and Aboriginal people to address them," Philip Bowles, IUCN SSC Snake and Lizard Red List Authority Coordinator, said in a statement.

Threats from invaders
Australia's reptile population has largely evolved in isolation, allowing for a diverse collection of species. In fact, Australia's reptile population represents almost 10 percent of the world's overall reptile fauna, according to the IUCN, making it a major hub of reptile species. Given their proliferation, it shouldn't be a surprise that reptiles, from lizards to pythons, play a large part in the country's ecosystems as well the culture of the indigenous people.

The dangers to the reptiles haven't come from within the borders of Australia — not exactly anyway. According to the IUCN, invasive species are the primary threat to over half of the threatened reptile species on the continent. The IUCN pointed to a January 2018 study, which determined that invasive feral cats alone are responsible for the deaths of 600 million reptiles a year.

The feral cat population in Australia varies wildly, but it's estimated to be between 2.1 and 6.3 million as of October 2017. The cats are present on practically the entire continent.

One species feral cats are particularly fond of is the grassland earless dragon (Tympanocryptis pinguicolla). This tiny dragon — it can grow to be about 16 centimeters — favors grassland areas, as its name suggests. In addition to the feral cats gobbling them up, habitat destruction and changes in wildfire patterns pose significant dangers to its survival. The species had adapted to semi-natural wildfires that have changed over the centuries thanks to different land management practices, according to the IUCN.

Cane toads were introduced to control species, not eliminate them entirely. (Photo: Ian Hitchcock/Getty Images)


Feral cats aren't the only invasive species causing problems for reptiles, however. Cane toads — which were introduced to Australia in 1935 to control beetle populations that destroyed lucrative sugar crops — have caused havoc with poisonous venom that can kill many native animals and their startlingly rapid evolution that allows them to hope in a straight line, covering more distance at a faster pace.

This is particularly bad for reptiles like Mitchell's Water Monitor (Varanus mitchelli), which dines on cane toads and then dies after doing so. The species is now considered critically endangered by the IUCN following a population decline of 97 percent in some areas.

Other animals aren't the only external threat, however. Climate change poses a serious danger to various reptiles, including the Bartle Frere cool-skink (Techmarscincus jigurru). This cold-adapted reptile favors the chilly climates of Mount Bartle Frere's summit. A temperature increase of 1 degree Celsius could result in a 50 percent loss in the lizard's population within 30 years since it won't have any place colder to move to. The species is already considered vulnerable.

"This Red List update highlights the vulnerability of Australia's lizards and snakes to invasive alien species, including the toxic cane toad and feral cats, often in combination with threats from habitat loss due to invasive weeds, development and fire."

 

[Mick666]

I think the real problem is licenced keepers taking reptiles from the wild, maybe if we bumped up the cost of permits, reduced the species list for keepers and generally make it harder for people to keep reptiles, the problem should disappear. Maybe if we severely restrict reptile breeding, it will have a positive effect on wild populations somehow. I don't see why anyone would want to keep a reptile when they could have a cute, cuddly kitten wandering the neighbourhood, killing those horrible snakes that are clearly out to get us.
[doublepost=1531271340,1531271195][/doublepost]Sorry for the sarcastic rant, I really hate cats and their irresponsible owners. It's one of my "pet hates".

 

[cris]

I think the real problem is licenced keepers taking reptiles from the wild, maybe if we bumped up the cost of permits, reduced the species list for keepers and generally make it harder for people to keep reptiles, the problem should disappear. Maybe if we severely restrict reptile breeding, it will have a positive effect on wild populations somehow.

Yeah, the last thing we want is lots of people breeding populations of endangered species for little to no cost, even possibly a profit. If something goes extinct in the wild we need to do everything we can to prevent their existence in captivity. We can only achieve this through authoritarian over-regulation, we should all try to pay more tax to promote this.

 

[Bluetongue1]

‘Publish or perish’, ‘got to make the editorial deadline’ or whatever credo reporters follow, does excuse this reporter’s shortcomings here. His statement: “the Red List, a rundown of threatened species around the globe” is not merely a misleading simplification, but a deliberate falsity in the given context in which it was used. He clearly seeks to convey the impression that “almost all of Australia’s reptiles” are classified as threatened species. The real reason all of Australia’s reptiles are not on the list is only because they lack ecological data or taxonomic clarity on all of them. The current Red List is a threat assessment data base for all species, and has been for the last quarter of a century. [For those not familiar with the Red List refer to the note at the end]

Then main reason for the catastrophic population declines in the Grassland Earless Dragon (Tympanocryptis pinguicolla) is loss of habitat and not feral cats as the reporter would have us believe. Cats are a part of the threat processes facing this lizard, and pretty much all small lizards for that matter, but are not the main factor in this instance. Alteration to grazing regimes to allow and encourage regrowth of native grasslands, and active regeneration in some cases, have seen significant population increases in areas where this has taken place. This has happened without any active control of cat populations, so draw your own conclusions.

If you are a reporter and want to do a piece on the effect of feral cats on Australia’s reptiles, then at least make the effort to present all the relevant facts and do so in a fair manner.


A Note on the Red List
“The IUCN Red List of Threatened Species” is a trade mark name and the list is no longer restricted to that originally established at its inception in 1964. The following is a quote from their official website…
The goal of The IUCN Red List is to:

• To provide information and analyses on the status, trends and threats to species in order to inform and catalyse action for biodiversity conservation.

This goal includes the "traditional" role of The IUCN Red List in identifying particular species at risk of extinction.
It also goes on to state that their target is: to make The IUCN Red List a "Barometer of Life" …and… The data cover non-threatened as well as threatened species.
The categories and criteria now used were established in 1994, and the procedures and standards required to meet these formalised accordingly. The current categories are: Extinct, Extinct in the Wild, Critically Endangered, Endangered, Vulnerable, Near Threatened, Least Concern, Data Deficient, Not Evaluated.