Our online forums with special guest speakers explore the complex world of invasive species in Australia.
Look around your garden or neighbourhood right now. What do you see? Can you pick the native species from the non-native?
What about in the trees and sky? Do sparrows, starlings and Indian mynas outnumber the pardalotes, parrots and rosellas?
Our new online Q&A Sessions: Aliens Among Us, are aimed at exploring the complex and chaotic world of invasive species in Australia. How did they get here? Are they harming our native ecosystems, plants and wildlife? And what’s being done to repair the damage they have caused up.
In this 11th episode of our Aliens Among Us Q&A webinar we were lucky to have Dr Brett Summerell, plant pathologist and the Chief Scientist & Director of Science, Education and Conservation at the Botanic Gardens of Sydney. He has professor roles with 3 universities and is an international authority on plant diseases and their impact on plant conservation.
We also have Tim Low AM, author and ecologist, co-founder of the Invasive Species Council and Dr Carol Booth, Invasive Species Council Principal Policy Analyst.
Question from Anon:
Thankyou for this opportunity to discuss.. My question is about what can be done in regards to protection, or treatment of botanic gardens/collections in areas prone to both myrtle rust and phytopthera? In my case close to Toowoomba & the Bunya Mountains?
The key thing to do would be to ensure that there are appropriate hygiene procedures in place before entering the botanic garden – either foot wash stations or some other form of boot cleaning strategy to make sure visitors are not bringing in Phytophthora with them. This can either be at the entry to the garden if that is feasible or in entry to critical areas such as a nursery. Keeping people on the paths is also important so they are not walking over the garden beds. It is difficult to keep Myrtle Rust out as the spores are airborne and can blow around.
Question from Andrew:
Brazil has invested millions in Eucalyptus plantations and obviously are concerned about the potential impacts of MR on these investments. Are we, in Australia, in discussion and sharing MR data/research with Brazil and vice versa?
Yes there are lots of global collaborations – particularly with researchers in Brazil and in those localities where the disease is problematic, especially in New Zealand and South Africa.
Question from Lee-Anne V:
Could there be any relationship between myrtle rust and the paralysis event impacting flying-foxes and lorikeets?
There is no indication that there is any association.
Question from Sharyn D:
How will myrtle rust affect the honey industry, especially for those apiarists that follow the flowers?
Potentially it can have an effect, depending on the plant species that the bees are visiting. If the plant species are affected then the flowering is reduced (or non-existent) and consequently less resources for the bees. This is a big concern in New Zealand with manuka honey.
Question from Vanda:
Can the virus die off naturally over time?
The pathogen is a fungus and there are no indications that it will die out. As long as there is a host it will keep reproducing. Of course if the host plants dies out the fungus will die out but we are a long way from that scenario.
Question from Sue C:
How quickly do trees take to die once infected?
It does depend on the species of tree – some are very susceptible and can die quite quickly (over a season) but others that are less susceptible will have a slow gradual demise – perhaps over a number of years.
Question from Anon:
Is any work being undertaken anywhere around the country to regrow endangered Australian native myrtaceae from seedbanks in protected environments?
There is some work happening in NSW and Qld to grow the most affected species. Unfortunately most of these species are difficult to store in seed banks as the seed of many rainforest Myrtaceae do not respond well to storage at low temperatures and many have not been able to produce seed because of the disease. Consequently it is necessary to collect cuttings and propagate in the nursery and grow the plants in pots; some grow well in tissue culture and research on cryopreservation is under way. Good collections of a number of severely affected species are now in botanic gardens and these are kept healthy via a rotation of different fungicides. All of this is very labour intensive, takes time and space.
Question from Brad:
How about Alpine or Cool Temperate Rainforest environments?
The Myrtle rust pathogen prefers warmer temperatures – it has evolved in Brazil – and so is not a significant issue in Alpine regions. This of course may change with climate change.
Question from Anon:
What procedures we should follow when Myrtle Rust is detected in our not for profit nursery?
It would be appropriate to consider application of fungicides if the plants are critical for conservation purposes. If they aren’t for that purpose it might be best to dispose of them as you will be continuously trying to keep the pathogen at bay.
Question from Michelle:
Should we be applying pre-emptive fungicide treatments?
Not likely to be effective – it is better to carefully monitor plants and consider use of fungicides at the first sign of the disease.
Question from Lee-Anne L:
What can individuals or on ground organisations do, if anything, to slow/stop Myrtle Rust?
At this point information is key – so monitoring for the presence of the disease and the species that are being affected. At the Atlas of Living Australia there is a citizen science program to help assist this.
Question from Lisa P:
Is there an interactive map showing where myrtle rust is present?
There are some resources on the ANPC website here and also on iNaturalist Gum Tree Guardians project page.
Question from Craig A:
How many species have been made functionally extinct as result of myrtle rust?
We have significant concerns about 16 species and there are another 27 species that need action. Over 380 species are known to be infected. Not all are functionally extinct – perhaps only 6 are heading that way immediately.
Question from Claire B:
Is there ANY hope at all? This seems very dire.
Yes there is – there is very promising research highlighting some ways in which this disease can be overcome but it will take resources and time.
Question from Janelle S:
How can the education around Myrtle rust and other diseases become ‘general knowledge’ so people are aware. Most people would not understand the impacts or even be aware of what Myrtle rust is doing so how do we move forward?
There are many efforts to raise awareness but we do suffer from a tendency to not care too much about plants and their role in ecosystem (just the green background). This is despite the fact that healthy plants are key to maintaining a healthy ecosystem and for fauna to survive.
Question from Belinda C:
I’m in Broome in the West Kimberley. Do we know how MR may react to many months of dry weather after a wet season? And from that, is MR destroyed by fire?
The spores can survive longish periods (3 months) and persist in the leaves. Fire will kill the pathogen in leaves if they burn but perversely the new growth post fires is much more susceptible to infection so you will expect there to be more myrtle rust after fire.
Question from Neil P:
What is happening about the Biological treatments? Timeframe to it being commercial? Information on getting involved in experimenting with this?
There has been some research on antagonistic microbes to the rust fungus but not with great effectiveness. Some RNA treatments show some promise.
In this 10th episode of our Aliens Among Us Q&A webinar we were lucky to have Dr Robert Puckett, associate professor and extension entomologist at Texas A&M University whose work on fire ants have significantly advanced our understanding of these tiny killers in Australia.
We also have Dr Rachel Chay, Queensland Chief Biosecurity Officer, overseeing Australia’s national fire ant eradication program and Reece Pianta, Invasive Species Council advocacy manager and fire ant specialist.
In this 10th episode of our Aliens Among Us Q&A webinar we were lucky to have Dr Jenny Newell as our special guest. Jenny is the author of Trading Nature: Tahitians, Europeans, and Ecological Exchange. She is also the visionary curator of Climate Change at the Australian Museum’s Climate Solutions Centre in Sydney.
We discuss the introduction of species to Tahiti, their environmental and cultural impact (and more!) which you can watch in the video below.
In this 9th episode of our Aliens Among Us Q&A webinar we are glad to have had Guy Hull as our special guest. Guy Hull is a best selling author, qualified dog behaviouralist and former recreational hunter. His most book from 2022 The Ferals that Ate Australia discusses the history of feral animals in Australia and the damage they’ve caused.
We discuss all of this and more which you can watch in the video below.
Additional Q&A
There were so many good questions we ran out of time to answer them all live! Our panel have taken the time to answer them below:
What is needed to create the cultural shift required for Australians to accept the responsibility of custodianship is everyone who has the ability to influence culture needs to do their part. Historians, authors, sports people, the arts, advertising etc.
– Richard Swain
As of March 2024, the total number of horses removed since November 2021 is 4,152, by a range of methods including aerial and ground shooting and some rehoming.
As a point of comparison for those numbers, over this same time period (since November 2021) more than 13,000 feral animals, including more than 8,000 feral deer, have also been shot in Kosciuszko National Park.
– Richard Swain
The removal of rodents from Lord Howe Island is a huge good news story. The native species are multiplying dramatically in response. Invasive mammals have also been removed from Macquarie Island and cats from a few islands, all with inspiring results. There are new biocontrol agents for weeds such as wandering trad (Tradescantia fluminensis) and sea spurge (Euphorbia paralias). A new fungicide will become available soon for myrtle rust control.
– Tim Low
It is widely believed that dingoes outcompeted tigers and preyed on devils, causing their extinction from the mainland (and also the mainland extinction of the Tasmanian native hen), although an alternative view is that increasing intense Aboriginal resource use played a larger role than dingoes. The marsupial lion (Thylacoleo) went extinct tens of thousands of years before dingoes arrived
– Tim Low
We agree it should be a high priority. For example, the Invasive Species Council has been advocating research on alternatives to 1080 baiting (currently essential for saving rare species). The recently developed Felixer is one example of a more targeted technology for cat and fox control.
– Dr Carol Booth
One example of drone use is for deploying baits near urban areas for the control of Fire Ants.
– Richard Swain
Yes, recent improvements in technology offer hope – new methods for detection (such as eDNA detectors and thermal imaging) and new methods for trapping and controlling species (such as the Felixer for cat control and the pheromone trap being developed for northern Pacific seastars).
– Dr Carol Booth
The most effective method for large-scale control of these predators is aerial baiting. Unfortunately, because cats prefer to take live prey, baiting is often ineffective for them. Developing effective large-scale methods for cat control is one of Australia’s most important conservation challenges.
– Dr Carol Booth
The harvesting of invasive species can be counterproductive. You can read more about that in our article here.
– Tim Low
We focus attention on the harm being done if pest animals are not killed, such as native animals killed by foxes and cats, and wildlife with no habitat because rabbits have prevented regeneration of mulga and myall woodlands.
– Tim Low
Every study of bounties finds that they do not work as expected. The money is worthwhile when the pest is plentiful but as soon as its numbers go down the rate of return decreases and people reduce their effort without the bounty having achieved a lasting benefit. ISC does not support bounties and nor do government pest experts.
– Tim Low
Feral horses through trashing and trampling cause enormous amounts of damage to our national parks and native wildlife, yet there are fringe groups of feral horse advocates who want them protected.
In this 8th episode of our Aliens Among Us webinar we have Dr Isa Menzies as our special guest. She is a cultural historian with a PhD in cultural studies from ANU and has published many scholarly articles on this topic. We dive in to find out they become bound up in the identity of a small but vocal minority? Why did the NSW government change laws to protect feral horses in a national park? Is there a connection between this and the voice referendum and more.
Additional Q&A
Our panel was kind enough to write some quick answers to some of the questions asked during the session that we didn’t have time to get to.
Our culture treats pigs as farm animals that end up as meat. Our culture treats horses as something we don’t normally kill. We don’t have strong cultural associations with deer.
– Tim
Yes there have been studies of damage that found it strongly associated with presence of horse dung, not deer or pig dung, eg. An assessment of feral horse impacts on treeless drainage lines in the Australian Alps, and Horse activity is associated with degraded subalpine grasslands structure and reduced habitat for a threatened
– Tim
They suffer greatly. Horse starvation is addressed here: https://theconversation.com/the-grim-story-of-the-snowy-mountains-cannibal-horses-31691
Rats that attack adult albatross and dive into water to prey on crabs. Possums that forgo their plant-based diet for native birds eggs. Welcome to the world of invasive species across the Tasman where masses of stoats, ferrets, possums, cats and weasels are playing havoc with nature. Like Australia, Aotearoa/New Zealand has experienced many extinctions and many more of their native species are in big trouble due to introduced species.
But New Zealanders agreed they were worth saving.
So, in 2016, they started Predator Free 2050 – an ambitious nationwide program to protect biodiversity by eliminating the country’s most damaging introduced predators.
But how did they rally Aotearoa/New Zealanders in a collective effort in the pursuit of this ‘crazy and ambitious’ goal to bring back their dawn chorus? Bringing government, community groups, Maori, charity groups and the community together to agree on anything is no easy feat, let alone for such a mammoth challenge.
Joining us will be:
All welcome to come along to this free webinar! Just note that registrations are essential and numbers are limited.
In 2016, Aotearoa/New Zealand started Predator Free 2050 – an ambitious nationwide program to protect biodiversity by eliminating the country’s most damaging introduced predators.
But how did they rally in a collective effort in the pursuit of this ‘crazy and ambitious’ goal to bring back their dawn chorus? Bringing government, community groups, Maori, charity groups and the community together to agree on anything is no easy feat, let alone for such a mammoth challenge.
Additional Q&A
Our panel was kind enough to write some quick answers to some of the questions asked during the session that we didn’t have time to get to.
Earlier this year, red fire ants were detected in the precious environments of Minjerribah (North Stradbroke Island) for the very first time. These highly invasive and dangerous ants were first found in Australia in 2001. A large outbreak in southeast Queensland remains active and is still subject to a major eradication effort. But if we fail to get on top of red fire ants, modelling shows they will spread to every corner of Australia. Our way of life will be changed forever.
Our expert panel, joined by Eli Perry from QYAC, talks with Sarah Corcoran who has been up close and personal with red fire ants and knows what’s at stake if fire ants swarm Australia.
On September 16, in response to allegations aired on shock-jock Sydney radio, the NSW Environment Minister announced a ban on all shooting operations in Kosciuszko National Park. The ban was supposed to only last two weeks. Five weeks later, not only was it still in place, but we learnt the ban had been applied to every national park across the entirety of NSW. The surge in feral animals being reported state-wide thanks to recent wet weather meant that the lack of feral animal control across NSW was jeopardising nature and livelihoods.
The issue of protecting Kosciuszko from feral horses is once again coming to a head.
Come behind the scenes with us in this Aliens Among Us session as we lift the lid on how we discovered feral animal control had been banned across the state of NSW, and how we worked with our tireless supporters to have the ban reversed.
Australia’s State of the Environment Report 2021, finally released earlier this year, makes for grim reading. But how central are invasive species to Australia’s extinction crisis? What can we take from the record level of Indigenous authorship in this edition of the report? What do cut flowers have to do with the state of Australia’s environment?
Our fourth Aliens Among Us session welcomes Barry Hunter, one of the co-authors of Australia’s latest State of the Environment Report. Alongside Barry is author and biologist Tim Low, Invasive Species Council Indigenous Ambassador Richard Swain, and Invasive Species Council CEO Andrew Cox as host.
Additional Q&A
Our panel was kind enough to write some quick answers to some of the questions asked during the session that we didn’t have time to get to.
Our third Aliens Among Us session welcomed John Read, ecologist and author of Among the Pigeons; Why our cats belong indoors. John is considered by some to be Australia’s leading expert on the impacts of feral and roaming cats, and this is a special opportunity to see the world of cats through his eyes.
Alongside John was our expert panel consisting of former Tasmanian Senator Christine Milne, author Tim Low and Invasive Species Council CEO Andrew Cox.
Additional Q&A
Our panel was kind enough to write some quick answers to the many questions that were asked during this session. It was fantastic to see so much interest in what is such a tricky issue to talk about!
es, any animal (including sheep, mice, humans, bandicoots and even seals etc) can become infected, but the Toxoplasmosis life cycle (production of oocysts) requires a Feline host, so Toxo will rapidly diminish without free-ranging cats. – John
For our first Aliens Among Us of 2022, we welcome Leslie Anthony – author of the book that we named this series after!
Join Leslie, former Tasmanian Senator Christine Milne, author Tim Low and Invasive Species Council CEO Andrew Cox as they explore the complex and chaotic world of invasive species.
Based in Whistler, Leslie is a writer, editor, biologist and occasional filmmaker. His former life as an editor for a number of acclaimed mountain and ski publications has left his name printed into the masthead of a swathe of magazines.
His zoology PhD from the University of Toronto and postdoctoral fellowship at McGill University’s Redpath Museum have left him well-equipped as he has turned his attention towards writing about travel, adventure and science.
Aside from being the inspiration (with permission!) for the name of this seminar series, his book ‘The Aliens Among Us: How Invasive Species are Transforming the Planet—and Ourselves’ is a thoughtful, accessible look at the rapidly growing issue of invasive plants, animals, and microbes around the globe. He draws on science, travel, history and humor to understand the ecological, social, and economic aspects to the burgeoning problem of invasive species.
Our first session stars Australian author Pete Minard, who wrote All Things Harmless, Useful and Ornamental.
Pete grew up in regional Australia surrounded by a landscape infested with rabbits, sparrows and hares. His fascination with how Australia’s landscape and ecology has changed through the introduction of non-native plants and animals reveals an intriguing history shaped and formed by the men behind early acclimatisation societies.
In his book he tells the story of this movement, arguing that far from attempting to re-create London or Paris, settlers sought to combine plants and animals to correct earlier environmental damage and to populate forests, farms, and streams to make them healthier and more productive.
By focusing particularly on the Australian colony of Victoria, Minard reveals a global network of would-be acclimatisers, from Britain and France to Russia and the United States.
Although the movement was short-lived, the long reach of nineteenth-century acclimatisation societies continues to be felt today, from choked waterways to the uncontrollable expansion of European pests in former colonies, including Australia.
The Invasive Species Council acknowledges the Traditional Custodians throughout Australia and their connections to land and sea. We pay our respect to their Elders past and present and extend that respect to all Aboriginal and Torres Strait Islander peoples today. The Invasive Species Council supports voting ‘YES’ for a Voice to Parliament.
Dear Project Team,
[YOUR PERSONALISED MESSAGE WILL APPEAR HERE.]
I support the amendment to the Kosciuszko National Park Wild Horse Heritage Management Plan to allow our incredible National Parks staff to use aerial shooting as one method to rapidly reduce feral horse numbers. I want to see feral horse numbers urgently reduced in order to save the national park and our native wildlife that live there.
The current approach is not solving the problem. Feral horse numbers have rapidly increased in Kosciuszko National Park to around 18,000, a 30% jump in just the past 2 years. With the population so high, thousands of feral horses need to be removed annually to reduce numbers and stop our National Park becoming a horse paddock. Aerial shooting, undertaken humanely and safely by professionals using standard protocols, is the only way this can happen.
The government’s own management plan for feral horses states that ‘if undertaken in accordance with best practice, aerial shooting can have the lowest negative animal welfare impacts of all lethal control methods’.
This humane and effective practice is already used across Australia to manage hundreds of thousands of feral animals like horses, deer, pigs, and goats.
Trapping and rehoming of feral horses has been used in Kosciuszko National Park for well over a decade but has consistently failed to reduce the population, has delayed meaningful action and is expensive. There are too many feral horses in the Alps and not enough demand for rehoming for it to be relied upon for the reduction of the population.
Fertility control as a management tool is only effective for a small, geographically isolated, and accessible population of feral horses where the management outcome sought is to maintain the population at its current size. It is not a viable option to reduce the large and growing feral horse population in the vast and rugged terrain of Kosciuszko National Park.
Feral horses are trashing and trampling our sensitive alpine ecosystems and streams, causing the decline and extinction of native animals. The federal government’s Threatened Species Scientific Committee has stated that feral horses ‘may be the crucial factor that causes final extinction’ for 12 alpine species.
I recognise the sad reality that urgent and humane measures are necessary to urgently remove the horses or they will destroy the Snowies and the native wildlife that call the mountains home. I support a healthy national park where native species like the Corroboree Frog and Mountain Pygmy Possum can thrive.
Dear Project Team,
[YOUR PERSONALISED MESSAGE WILL APPEAR HERE.]
I support the amendment to the Kosciuszko National Park Wild Horse Heritage Management Plan to allow our incredible National Parks staff to use aerial shooting as one method to rapidly reduce feral horse numbers. I want to see feral horse numbers urgently reduced in order to save the national park and our native wildlife that live there.
The current approach is not solving the problem. Feral horse numbers have rapidly increased in Kosciuszko National Park to around 18,000, a 30% jump in just the past 2 years. With the population so high, thousands of feral horses need to be removed annually to reduce numbers and stop our National Park becoming a horse paddock. Aerial shooting, undertaken humanely and safely by professionals using standard protocols, is the only way this can happen.
The government’s own management plan for feral horses states that ‘if undertaken in accordance with best practice, aerial shooting can have the lowest negative animal welfare impacts of all lethal control methods’.
This humane and effective practice is already used across Australia to manage hundreds of thousands of feral animals like horses, deer, pigs, and goats.
Trapping and rehoming of feral horses has been used in Kosciuszko National Park for well over a decade but has consistently failed to reduce the population, has delayed meaningful action and is expensive. There are too many feral horses in the Alps and not enough demand for rehoming for it to be relied upon for the reduction of the population.
Fertility control as a management tool is only effective for a small, geographically isolated, and accessible population of feral horses where the management outcome sought is to maintain the population at its current size. It is not a viable option to reduce the large and growing feral horse population in the vast and rugged terrain of Kosciuszko National Park.
Feral horses are trashing and trampling our sensitive alpine ecosystems and streams, causing the decline and extinction of native animals. The federal government’s Threatened Species Scientific Committee has stated that feral horses ‘may be the crucial factor that causes final extinction’ for 12 alpine species.
I recognise the sad reality that urgent and humane measures are necessary to urgently remove the horses or they will destroy the Snowies and the native wildlife that call the mountains home. I support a healthy national park where native species like the Corroboree Frog and Mountain Pygmy Possum can thrive.