Each year, from September to mid-October, the tiny and very precious mountain pygmy-possums arise from their months of hibernation under the snow and begin feasting on billions of bogong moths that migrate from Queensland to Victoria’s alpine region.
But for the past two springs, moth numbers have collapsed from around 4.4 billion in alpine areas to an almost undetectable number of individuals. And the mountain pygmy-possums went hungry, dramatically affecting breeding success among the last remaining 2,000 that live in the wild.
This year’s migration of bogong moths to the possums’ alpine home is crucial for the critically endangered mountain pygmy-possums. That’s why we’re asking you to do two simple things: turn off your lights at night, and if you see a bogong moth, take a picture.
What’s happened to the moths?
We don’t know exactly why the moths are not making it to their summer alpine destination. It’s likely extreme drought, pesticides and changes in agricultural practices are all major factors. However, scientists believe that because moths use both the Earth’s magnetic field and visual cues on the horizon to navigate, light pollution from urban centres can confuse the moths and stall their journey.
Some of the greatest beacons on their path are Parliament House and Canberra’s bright surrounds. Both parliamentarians and the general public are being asked to turn unnecessary outdoor lights off from September 1 to October 31, as part of the Lights Off for Moths campaign.
Artificial night lighting has dramatically changed the nocturnal environment. In urban environments, the soft glow of moonlight is overpowered by bright streetlights, security lights and car headlamps. These light sources can be more than 1,000 times as bright as moonlight, and their biological impact is increasingly visible and widespread.
One of the most obvious impacts of artificial light at night is that it can attract animals (sometimes fatally). While a “moth to a flame” may be somewhat poetic, when one moth becomes hundreds, or potentially thousands, the ecological impact may be catastrophic. Current global lighting practices may be creating this very scenario.
Recent evidence links the presence of artificial light at night with large-scale deaths and shifts in nocturnal migration patterns in birds. In insects, artificial night lighting disrupts nocturnal pollination networks and is strongly linked with observed mass declines in insect (and particularly moth) populations.
No moths means hungry possums
When a species like bogong moths decline, it has huge ramifications. Insects in particular are vital pillars supporting whole ecosystems – without bees and other insect pollinators, for example, we risk the extinction of our flowering plants. Many birds, reptiles and mammals depend on insects as part of their diet.
For mountain pygmy possums, the fatty, nutrient-rich bounty of bogong moths arrives right as they are waking up in the spring. They are one of the only Australian mammals that hibernate, and can spend up to seven months sleeping under the alpine snow.
The possums awake ravenously hungry, and devour the bogong moths to regain crucial fat stores. Without the moths there at the right time, the possums struggle to secure enough energy to breed successfully.
Snap that moth
Alongside the Lights Off for Moths campaign, Zoos Victoria has launched Moth Tracker, an app that allows Australians to photograph and log any potential sightings of migrating bogong moths.
Moth Tracker, which can be accessed through any laptop or smartphone, is adapted from the popular Southern Right Whale watching app in collaboration with Federation University and Victorian conversation network SWIFFT.
Bogong moths migrate from their winter breeding grounds throughout Queensland, New South Wales and western Victoria in search of cooler climates for the spring and summer in the Victorian and NSW Alpine regions where the mountain pygmy-possums live.
Before they become moths, the larvae look like tiny, shiny brown capsules and are commonly referred to as cutworm. Migratory bogong moths are dark brown, with two lighter spots on each wing. They are small, only about the length of a paper clip. During the day they’re often seen grouped together like roof tiles. At night, they are more active and flying around.
If you see a bogong moth (or something you think might be a bogong month), we need you to take a photograph and log the location, day and time with Moth Tracker. Scientists will use the data to determine whether any moths are making their way to the precious, and very hungry, possums that are just starting to wake from their winter hibernation.
The Victorian Mountain Pygmy-possum Recovery Team, together with partner organisations, is also investigating options for interventions in the wild if needed. These may include a world-first airdropping of “bogong balls” to feed the hungry possums, as well as improving habitat connectivity and captive measures to support populations through the breeding season.
But with unnecessary outdoor lights switched off and citizen scientists looking out for bogong moths, there is still hope for the mountain pygmy-possums.
Michelle Ward, The University of Queensland; April Reside, The University of Queensland; Hugh Possingham, The University of Queensland; James Watson, The University of Queensland; Jeremy Simmonds, The University of Queensland; Jonathan Rhodes, The University of Queensland, and Martin Taylor, The University of Queensland
Threatened species habitat larger than the size of Tasmania has been destroyed since Australia’s environment laws were enacted, and 93% of this habitat loss was not referred to the federal government for scrutiny, our new research shows.
The research, published today in Conservation Science and Practice, shows that 7.7 million hectares of threatened species habitat has been destroyed in the 20 years since the Environment Protection and Biodiversity Conservation (EPBC) Act 1999 came into force.
Some 85% of land-based threatened species experienced habitat loss. The iconic koala was among the worst affected. More than 90% of habitat loss was not referred or submitted for assessment, despite a requirement to do so under Commonwealth environment laws.
Our research indicates the legislation has comprehensively failed to safeguard Australia’s globally significant natural values, and must urgently be reformed and enforced.
What are the laws supposed to do?
The EPBC Act was enacted in 1999 to protect the diversity of Australia’s unique, and increasingly threatened, flora and fauna. It was considered a giant step forward for biodiversity conservation and was expected to become an important legacy of the Howard Coalition government.
The law aims to conserve so-called “protected matters” such as threatened species, migratory species, and threatened ecosystems.
Clearing and land use change is regarded by ecologists as the primary threat to Australia’s biodiversity. In Queensland, land clearing to create pasture is the greatest pressure on threatened flora and fauna.
Any action which could have a significant impact on protected matters, including habitat destruction through land clearing, must be referred to the federal government for assessment.
The law is not being followed
We examined federal government forest and woodland maps derived from satellite imagery. The analysis showed that 7.7 million hectares of threatened species habitat has been cleared or destroyed since the legislation was enacted.
Of this area, 93% was not referred to the federal government and so was neither assessed nor approved.
It is unclear why people or companies are not referring habitat destruction on such a large scale. People may be self-assessing their activities and concluding they will not have a significant impact.
Others may be seeking to avoid the expense of a referral, which costs A$6,577 for people or companies with a turnover of more than A$10 million a year.
The failure to refer may also indicate a lack of awareness of, or disregard for, the EPBC Act.
The biggest losers
Our research found that 1,390 (85%) of terrestrial threatened species experienced habitat loss within their range since the EPBC Act was introduced.
Among the top ten species to lose the most area were the red goshawk, the ghost bat, and the koala, losing 3 million, 2.9 million, and 1 million hectares, respectively.
In less than two decades, many other imperilled species have lost large chunks of their potential habitat. They include the Mount Cooper striped skink (25%), the Keighery’s macarthuria (23%) and the Southern black-throated finch (10%).
What’s working, what’s not
We found that almost all referrals to the federal government for habitat loss were made by urban developers, mining companies and commercial developers. A tiny 1.3% of referrals were made by agricultural developers – despite clear evidence that land clearing for pasture development is the primary driver of habitat destruction.
Alarmingly, even when companies or people did refer proposed actions, 99% were allowed to proceed (sometimes with conditions).
The high approval rates may be derived, in part, from inconsistent application of the “significance” test under the federal laws.
For example, in a successful prosecution in 2015, Powercor Australia and Vemco] were fined A$200,000 for failing to refer clearing of a tiny 0.5 hectares of a critically endangered ecosystem. In contrast, much larger tracts of habitat have been destroyed without referral or approval, and without any such enforcement action being taken.
Clearer criteria for determining whether an impact is significant would reduce inconsistency in decisions, and provide more certainty for stakeholders.
The laws must be enforced and reformed
If the habitat loss trend continues, two things are certain: more species will become threatened with extinction, and more species will become extinct.
The Act must, as a matter of urgency, be properly enforced to curtail the mass non-referral of actions that our analysis has revealed.
If nothing else, this will help Australia meet its commitment under the Convention on Biological Diversity to prevent extinction of known threatened species and improve their conservation status by 2020.
Mapping the critical habitat essential to the survival of every threatened species is also an important step. The Act should also be reformed to ensure critical habitat is identified and protected, as happens in the United States.
Australia is already a world leader in modern-day extinctions. Without a fundamental change in how environmental law is written, used, and enforced, the crisis will only get worse.
Michelle Ward, PhD Student, The University of Queensland; April Reside, Researcher, Centre for Biodiversity and Conservation Science, The University of Queensland; Hugh Possingham, Professor, The University of Queensland; James Watson, Professor, The University of Queensland; Jeremy Simmonds, Postdoctoral Research Fellow in Conservation Science, The University of Queensland; Jonathan Rhodes, Associate Professor, The University of Queensland, and Martin Taylor, Adjunct senior lecturer, The University of Queensland
Jaco Le Roux, Macquarie University; Florencia Yanelli, Stellenbosch University; Heidi Hirsch, Stellenbosch University; José María Iriondo Alegría, Universidad Rey Juan Carlos; Marcel Rejmánek, University of California, Davis, and Maria Loreto Castillo, Stellenbosch University
Earth is seeing an unprecedented loss of species, which some ecologists are calling a sixth mass extinction. In May, a United Nations report warned that 1 million species are threatened by extinction. More recently, 571 plant species were declared extinct.
But extinctions have occurred for as long as life has existed on Earth. The important question is, has the rate of extinction increased? Our research, published today in Current Biology, found some plants have been going extinct up to 350 times faster than the historical average – with devastating consequences for unique species.
Measuring the rate of extinction
“How many species are going extinct” is not an easy question to answer. To start, accurate data on contemporary extinctions are lacking from most parts of the world. And species are not evenly distributed – for example, Madagascar is home to around 12,000 plant species, of which 80% are endemic (found nowhere else). England, meanwhile, is home to only 1,859 species, of which 75 (just 4%) are endemic.
Areas like Madagascar, which have exceptional rates of biodiversity at severe risk from human destruction, are called “hotspots”. Based purely on numbers, biodiversity hotspots are expected to lose more species to extinction than coldspots such as England.
But that doesn’t mean coldspots aren’t worth conserving – they tend to contain completely unique plants.
We are part of an international team that recently examined 291 modern plant extinctions between biodiversity hot- and coldspots. We looked at the underlying causes of extinction, when they happened, and how unique the species were. Armed with this information, we asked how extinctions differ between biodiversity hot- and coldspots.
Unsurprisingly, we found hotspots to lose more species, faster, than coldspots. Agriculture and urbanisation were important drivers of plant extinctions in both hot- and coldspots, confirming the general belief that habitat destruction is the primary cause of most extinctions. Overall, herbaceous perennials such as grasses are particularly vulnerable to extinction.
However, coldspots stand to lose more uniqueness than hotspots. For example, seven coldspot extinctions led to the disappearance of seven genera, and in one instance, even a whole plant family. So clearly, coldspots also represent important reservoirs of unique biodiversity that need conservation.
We also show that recent extinction rates, at their peak, were 350 times higher than historical background extinction rates. Scientists have previously speculated that modern plant extinctions will surpass background rates by several thousand times over the next 80 years.
So why are our estimates of plant extinction so low?
First, a lack of comprehensive data restricts inferences that can be made about modern extinctions. Second, plants are unique in – some of them live for an extraordinarily long time, and many can persist in low densities due to unique adaptations, such as being able to reproduce in the absence of partners.
Let’s consider a hypothetical situation where we only have five living individuals of Grandidier’s baobab (Adansonia grandidieri) left in the wild. These iconic trees of Madagascar are one of only nine living species of their genus and can live for hundreds of years. Therefore, a few individual trees may be able to “hang in there” (a situation commonly referred to as “extinction debt”) but will inevitably become extinct in the future.
Finally, declaring a plant extinct is challenging, simply because they’re often very difficult to spot, and we can’t be sure we’ve found the last living individuals. Indeed, a recent report found 431 plant species previously thought to be extinct have been rediscovered. So, real plant extinction rates and future extinctions are likely to far exceed current estimates.
There is no doubt that biodiversity loss, together with climate change, are some of the biggest challenges faced by humanity. Along with human-driven habitat destruction, the effects of climate change are expected to be particularly severe on plant biodiversity. Current estimates of plant extinctions are, without a doubt, gross underestimates.
However, the signs are crystal clear. If we were to condense the Earth’s 4.5-billion-year-old history into one calendar year, then life evolved somewhere in June, dinosaurs appeared somewhere around Christmas, and the Anthropocene starts within the last millisecond of New Year’s Eve. Modern plant extinction rates that exceed historical rates by hundreds of times over such a brief period will spell disaster for our planet’s future.
Jaco Le Roux, Associate Professor, Macquarie University; Florencia Yanelli, Researcher, Stellenbosch University; Heidi Hirsch, Postdoctoral research fellow, Stellenbosch University; José María Iriondo Alegría, Catedrático de universidad en el área de Botánica, Universidad Rey Juan Carlos; Marcel Rejmánek, Emeritus professor, University of California, Davis, and Maria Loreto Castillo, PhD Candidate, Stellenbosch University
A recent survey on the world’s plants found a shocking number have gone extinct – 571 since 1750. And this is likely to be a stark underestimate. Not all plants have been discovered, so it’s likely other plants have gone extinct before researchers know they’re at risk, or even know they exist.
In Australia, the situation is just as dire. The Threatened Species Recovery Hub recently conducted two evaluations that aren’t yet published of extinct plants in Australia. They found 38 have been lost over the last 170 years, such as the Daintree River banana (Musa fitzalanii) and the fringed spider-orchid (Caladenia thysanochila).
But uncertainty about the number of plant extinctions, in addition to the 38 confirmed, is an ongoing concern.
Both studies pointed out the actual number of extinctions is likely to be far more than those recognised in formal lists produced by the Commonwealth and state and territory agencies.
For example, there is still a high rate of discovery of new plant species in Australia. More than 1,600 plants were discovered between 2009 and 2015, and an estimated 10% are still yet to be discovered.
The extinction of Australian plants is considered most likely to have occurred in areas where there has been major loss and degradation of native bushland. This includes significant areas in southern Australia that have been cleared for agriculture and intensive urbanisation around major cities.
Many of these extinct plants would have had very restricted geographic ranges. And botanical collections were limited across many parts of Australia before broad scale land clearing and habitat change.
Why extinction goes undocumented
There is already one well recognised Australian plant extinction, a shrub in Phillip Island (Streblorrhiza speciosa), which was never formally recognised on any Australian threatened species list.
Researchers also note there are Australian plants that are not listed as extinct, but have not been collected for 50 years or more.
While undocumented extinction is an increasing concern, the recent re-assessment of current lists of extinct plants has provided a more positive outcome.
The re-assessment found a number of plants previously considered to be extinct are not actually extinct. This includes plants that have been re-discovered since 1980, and where there has been confusion over plant names. Diel’s wattle (Acacia prismifolia), for instance, was recently rediscovered in Western Australia.
A significant challenge for accurately assessing plant extinction relates to the difficulties in surveying and detecting them in the Australian landscapes.
Many have histories associated with fire or some other disturbance. For example, a number of plants spend a significant part of their time as long-lived seeds – sometimes for decades – in the soil with nothing visible above ground, and with plants only appearing for a few years after a fire.
But by far, the greatest reason for the lack of information is the shortage of field surveys of the rare plants, and the availability of botanists and qualified biologists to survey suitable habitat and accurately identify the plants.
What we’ve learnt
The continuing decline of Australia’s threatened plants suggests more extinctions are likely. But there have been important achievements and lessons learnt in dealing with the main causes of loss of native vegetation.
Our understanding of plant extinction processes – such as habitat loss, habitat degradation, invasive weeds, urbanisation, disease and climate change – is improving. But there is still a significant way to go.
One challenge in dealing with the causes of Australian plant extinction is how to manage introduced diseases.
Two plant diseases in particular are of major concern: Phytophthora dieback, a soil-borne water mould pathogen, and Myrtle rust, which is spread naturally by wind and water.
Both diseases are increasingly recognised as threats, not only because of the impact they are already having on diverse native plant communities and many rare species, but also because of the difficulties in effective control.
Two Australian rainforest tree species Rhodomyrtus psidioides and Rhodamnia rubescens were recently listed as threatened under the NSW legislation because of myrtle rust.
While extinction associated with disease is often rapid, some individual plants may survive for decades in highly degraded landscapes, such as long-lived woody shrubs and trees. These plants will ultimately go extinct, and this is often difficult to communicate to the public.
While individual species will continue to persist for many years in highly disturbed and fragmented landscapes, there is little or no reproduction. And with their populations restricted to extremely small patches of bush, they’re vulnerable to ongoing degradation.
In many such cases there is an “extinction debt”, where it may take decades for extinction to occur, depending on the longevity of the plants involved.
But it’s not all doom and gloom. A recent study found of the 418 threatened Australian plants showing ongoing decline, 83% were assessed as having medium to high potential for bouncing back.
And with long-term investment and research there are good prospects of saving the majority of these plants.