Half the world’s ecosystems at risk from habitat loss, and Australia is one of the worst

James Watson, The University of Queensland; Eve McDonald-Madden, The University of Queensland; James Allan, The University of Queensland; Kendall Jones, The University of Queensland; Moreno Di Marco, The University of Queensland, and Richard Fuller, The University of Queensland

Habitat loss is the most insidious of all threats facing land-living wildlife, and protected areas like national parks are one of the best ways to combat the destruction. But in research published recently in Conversation Letters, we show that in some places the pace of protected areas isn’t keeping up with the losses.

We found that since 1992, an area of natural habitat two-thirds the size of Australia has been converted to human use (such as farms, logging or cities). Half of the world’s land area is now dominated by humans.

When we looked at specific habitats (or “ecoregions”), we found that in almost half of them, more habitat has been lost than has been protected. Of developed nations, Australia is performing the worst.

This week, 196 signatory nations of the Convention of Biological Diversity, including Australia, are meeting in Cancun, Mexico, to discuss their progress towards averting the current biodiversity crisis.

While topics will vary widely from dealing with climate change, invasive species and illegal wildlife trade, a chief issue will likely be one that has been central to the convention since its ratification at Rio in 1992: how best to deal with habitat loss.

The view from space

Human activity affects the planet on a scale so vast it can be easily seen from space. Whether it’s deforestation in the Amazon, urban development in Asia, or mining in the Arctic, humans have modified Earth’s land area dramatically.

For almost all wild species on Earth, once the places they live have been dramatically altered, they are unable to survive in the long term. The number of vertebrate species extinctions has been 53 times higher than normal since 1900, and the majority of them are associated with direct habitat loss.

The best tool we have at our disposal to combat habitat loss, alongside strict land regulation, is the creation of large, well-connected protected areas, especially in places that are likely to be at risk of future destruction.

When well managed and strategically placed, protected areas work at protecting biodiversity from destructive actives such as agriculture, mining and urbanisation.

In the two and a half decades since the Rio de Janeiro Earth Summit in 1992, there has been a dramatic increase in protected areas. Now 15% of the land is placed under protection – an area greater than South and Central America combined.

That’s the good news. The bad news is that it may not be enough.

Half Earth

Using the latest update of the global human footprint, we discovered that while 75% of the world has a clear human footprint, more than 50% of the world’s land area has been significantly converted to human dominated land uses.

The degree of degradation varies across the major ecosystems. Some areas such as the tundra have been only slightly modified. Other ecosystems have been decimated: 90% of mangroves and sub-tropical forests have been converted to human uses.

Concerningly, since the convention was ratified in 1992, an extra 4.5 million square kilometres of land has been converted from natural habitat to human land uses. And much of this loss occurred in areas that already faced considerable losses in the past.

As a consequence, almost half of the world’s 800 ecoregions – those places that have distinct animal and plant communities – should be classified at very high risk, where 25 times more land has been converted than protected.

Forty-one of these ecoregions are in crisis, where humans converted more than 10% of the little remaining habitat over the past two decades and there is almost nothing left to protect.

41 of the world’s ecoregions are in crisis.

These crisis ecoregions are concentrated in Southeast Asia (Indonesia and Papua New Guinea), and Africa (Madagascar, Democratic Republic of the Congo and Angola). It’s crucial that we establish protected areas in these places, but conflict and corruption make them some of the hardest places for conservation to work.

Australia: world expert in land clearing

While crisis ecoregions are mostly confined to the developing world, arguably the most concerning outcome of our research is that in many developed countries, like the United States and Canada, the proportion of protected areas to habitat loss is slipping.

And Australia is the worst performing developed nation of them all. Habitat loss greatly outpaced protection in 20 of Australia’s most wildlife-rich ecoregions. The most threatened ecoregions now include savannas in the southeast and southwest of Australia, and southeast temperate forest ecosystems.

Our analysis shows massive habitat loss occurred in Queensland, New South Wales and Western Australia during the past two decades, driven by land clearing for pasture, agriculture and urbanisation.

Australia has extremely high land-clearing rates and is the only developed nation now containing a deforestation front.

Arguably, things will continue to get worse without land-clearing law reform, but this is challenging, as shown by the recent failure of Queensland’s vegetation law changes and the poor vegetation-offset reforms in New South Wales.

Time for global action

As nations meet in Mexico to discuss their progress towards the Convention of Biological Diversity’s 2020 strategic plan, it is now time for them to undertake a full, frank and honest assessment on how things are progressing.

This means recognising that the current situation, where nations only report on protected area expansion, clearly tells half the story – and it is jeopardising the chance for halting the biodiversity crisis.

Australia must take the lead. It is time for this nation – one of the most wildlife-rich in the developed world – to account fully for both conservation gains and losses, and as such formally report on how much habitat is being destroyed. This is the necessary first step to identify ways to mitigate these losses and prioritise conservation actions in those regions that are at risk.

At the same time, all nations must recognise that the integrity of habitat within existing protected areas must be maintained, especially in those areas that contain imperilled species. Allowing activities which cause habitat loss to occur in protected areas is a backwards step for conservation, and governments must enforce their own environmental policies to stop this.

A good example is Springvale Station in Queensland, where mining is being considered within a newly purchased protected area, clearly threatening its biodiversity.

We need to change how we report on, and deal with, habitat loss, otherwise the mission of the convention – to stop the global extinction crisis – will fail.

The Conversation

James Watson, Associate Professor, The University of Queensland; Eve McDonald-Madden, Senior lecturer, The University of Queensland; James Allan, PhD candidate, School of Geography, Planning and Environmental Management, The University of Queensland; Kendall Jones, PhD candidate, Geography, Planning and Environmental Management, The University of Queensland; Moreno Di Marco, Postdoctoral Researcher in Conservation Biology, The University of Queensland, and Richard Fuller, Associate professor, The University of Queensland

This article was originally published on The Conversation. Read the original article.


It’s time to stand tall for imperilled giraffes

Bill Laurance, James Cook University

Pardon the pun, but it’s time to stick our necks out for giraffes. We have mistakenly taken the world’s tallest mammal for granted, fretting far more about other beloved animals such as rhinos, elephants and great apes.

But now it seems that all is not well in giraffe-land, with reports emerging that they may be staring extinction in the face.

Why? For starters, thanks to modern molecular genetics, we have just realised that what we thought was one species of giraffe is in fact four, split into between seven and nine distinct subspecies. That’s a lot more biodiversity to worry about.

The current distribution of recognised giraffe species and subspecies.
Narayanese at English Wikipedia

Even more disturbing is the fact that giraffe populations are collapsing. Where once they roamed widely across Africa’s savannas and woodlands, they now occupy less than half of the real estate they did a century ago.

Where they still persist, giraffe populations are increasingly sparse and fragmented. Their total numbers have fallen by 40% in just the past two decades, and they have disappeared entirely from seven African countries.

Among the most imperilled is the West African giraffe, a subspecies now found only in Niger. It dwindled to just 50 individuals in the 1990s, and was only saved by desperate last-ditch efforts from conservationists and the Niger government.

As a result of these sharp declines, the International Union for the Conservation of Nature recently changed giraffes’ overall conservation status from “Least Concern” to “Vulnerable”. In biological terms, that’s like a ship’s pilot suddenly bellowing “iceberg dead ahead!”

Tall order

Why are giraffes declining so abruptly? One reason is that they reproduce slowly, as might be expected of a big animal that formerly had to contend only with occasional attacks by lions, hyenas and tribal hunters, and as a result is not well adapted to our hostile modern world.

Giraffes today are being hit by much more than traditional enemies. According to the United Nations, Africa’s population of 1.1 billion people is growing so fast that it could quadruple this century. These extra people are using lots more land for farming, livestock and burgeoning cities.

Blocked by fences: a giraffe held in a small game reserve in South Africa.
Bill Laurance

Beyond this, Africa has become a feeding ground for foreign corporations, especially big mining firms from China, Australia and elsewhere. To export bulk commodities such as iron, copper and aluminium ore, China in particular has gone on a frenzy of road, railway and port building.

Fuelled by a flood of foreign currency, Africa’s infrastructure is booming. A total of 33 “development corridors” – centred around ambitious highway and rail networks – have been proposed or are under active construction. Our research shows that these projects would total more than 53,000km in length, crisscrossing the continent and opening up vast expanses of remote, biologically rich ecosystems to new development pressures.

Proposed and ongoing ‘development corridors’ in sub-Saharan Africa, ranked by the relative conservation value of habitats likely to be affected by each corridor.
Bill Laurance/Sean Sloan

Meanwhile, giraffes are struggling to cope with poachers armed with powerful automatic rifles rather than customary weapons such as spears. As shown in this poignant video, giraffes are commonly killed merely for their tails, which are valued as a status symbol and dowry gift by some African cultures.

Time to act

For a group of species about which we had been largely complacent, the sudden shift to “Vulnerable” status for giraffes is a red flag telling us it’s time for action.

Giraffes’ sweeping decline reflects a much wider trend in wildlife populations. A recent WWF report forecasts that we are on track to lose two-thirds of all individual birds, mammals, reptiles, amphibians and fish on Earth by 2020. Species in tropical nations are doing especially poorly.

What can we do? A critical first step is to help African nations develop their natural resources and economies in ways that don’t decimate nature. This is an urgent challenge that hinges on improving land-use planning, governance and protection of nature reserves and imperilled wildlife.

Woodland clearing for agriculture in Botswana’s Okavango Delta.
Jeremy Hance

We can also use emerging technologies to help us. For example, it is now possible to monitor illegal deforestation, road-building and other illicit activities virtually in real time, thanks to remarkable advances in satellites, drones, computing and crowdsourcing.

What’s more, affordable automatic cameras are being widely used to monitor the status of wildlife populations. These are particularly useful for giraffes, which have individual mottling patterns as distinctive as human fingerprints.

But all the technology in the world won’t save wildlife if we don’t address the fundamental drivers of Africa’s plight: its booming population and desperate needs for equitable social and sustainable development.

Ignoring these basic needs while tackling poaching and illegal road-building is akin to plugging the holes in a dam while ignoring the rising flood-waters that threaten to spill over its top.

We have to redouble our efforts, pushing for conservation and more sustainable societies all at once – plugging the holes while at the same time building the dam higher.

For the stately giraffe and the rest of Africa’s declining wildlife, it’s time for us to stand tall – or else wave goodbye.

Giraffes on the Serengeti Plain of Tanzania.
Bill Laurance

The Conversation

Bill Laurance, Distinguished Research Professor and Australian Laureate, James Cook University

This article was originally published on The Conversation. Read the original article.

Eradicating fire ants is still possible, but we have to choose now

Daniel Spring, University of Melbourne; Jonathan Keith, Monash University, and Tom Kompas, University of Melbourne

Australia needs to spend millions of dollars more to eradicate one of the nation’s worst invasive species, the fire ant, according to recent reports.

Fire ants, first detected in Brisbane in 2001, pose a major health and agricultural risk. A recent independent review of the eradication program recommended that A$380 million be spent over 10 years to eradicate the ants, on top of the A$330 million already spent since 2001.

Improvements in knowledge and control methods mean that eradicating the Australian invasion is challenging, but still potentially feasible. We now face a stark choice.

Lessons from previous attempts

The fire ant eradication program began in September 2001 after the species was detected at two locations in Brisbane. By that time, it may have been present for at least five years or perhaps even longer, and large areas were already infested. Fire ants had never been eradicated from areas this large.

However, improved eradication methods mean we have increased the chances of eradicating larger invasions.

Most of the original funds were spent on pesticides and monitoring areas with likely infestations. Monitoring information was used to estimate how far the invasion had spread (“delimitation”) and management efforts were focused on the delimited area.

The early years of the program showed that large infestations, such as those at the Port of Brisbane and Yarwun, can be eradicated when the geographic range of the infestations is known.

However, when this is not the case, undetected nests beyond the known infested area can spread unchecked. In a published reconstruction of the invasion we estimated that undetected nests existed a relatively short distance beyond the delimited area.

Had those nests been detected by monitoring a larger area over the first few years of the program, the ants may already have been eradicated. However, the initial focus on intensively treating known infestations rather than expanding the monitored area reflected the best available scientific advice at the time.

It also reflected an urgent need to protect people from the potentially serious health consequences of coming into contact with fire ants in areas known to be infested.

Pustules caused by fire ant stings.
Daniel Spring, Author provided

Is eradication still possible?

Although the invasion now occupies a larger area than it did when the program began, fire ant numbers have effectively been suppressed and some individual infestations have been eradicated. These facts, and the availability of a cheaper monitoring method involving remote sensing with airborne cameras, have kept alive eradication hopes.

A recent meeting of agricultural ministers agreed with the finding of the independent review that eradication remains technically feasible.

The review’s recommendation that eradication program funding be increased is a logical response to the invasion’s expansion. The expansion not only increased the area that requires management, thus increasing costs, but also showed that the areas previously searched and treated each year were too small to achieve eradication, implying there was insufficient annual funding.

Geographic expansion of the invasion cannot continue much longer without the invasion becoming too large to eradicate. The review panel’s finding that increased funding should be made available soon is therefore timely.

A lack of monitoring during the early years of the program led to the erroneous conclusion in 2004 that eradication was imminent, when in fact the invasion was expanding in area. To avoid this mistake being repeated, substantial monitoring will be required beyond known infestations and monitoring data will need to be assessed with reliable statistical methods.

In a recent report we wrote to help the eradication program, we showed that the invasion boundary can be estimated with a high degree of confidence if adequate monitoring data are available.

Pesticide treatment and monitoring will underpin eradication efforts. We need highly sensitive monitoring methods, including sniffer dogs and trained spotters, to confirm absence of fire ants in and near treated locations.

A large enough area should be monitored to ensure all fire ant colonies are found and removed. We need continued support for community members to report fire ants, particularly in urban areas. Remote sensing will be needed in less developed areas where contact between people and fire ants is less likely.

A stark choice

The choice is to continue eradication efforts or live with fire ants forever. Living with fire ants will incur large costs for agricultural producers and households.

The most recent cost-benefit analysis of the program estimated that if these costs were added up over each of the next 70 years they would exceed A$25 billion in today’s dollars.

Over half these estimated costs arise from damage to agricultural activities, with household losses being of a similar magnitude.

Large numbers of people are likely to come into contact with fire ants if the species is left unchecked. Environmental damages could also be substantial. These losses far exceed estimated eradication costs.

The review panel’s report makes it clear that we face an urgent choice between increased eradication funding or living with fire ants. There is not much time left to make this choice.

The Conversation

Daniel Spring, Research Fellow, School of Biosciences, University of Melbourne; Jonathan Keith, Associate Professor, School of Mathematical Sciences, Monash University, and Tom Kompas, , University of Melbourne

This article was originally published on The Conversation. Read the original article.