NZ’s next large Alpine Fault quake is likely coming sooner than we thought, study shows

Jamie Howarth, Te Herenga Waka — Victoria University of Wellington and Rupert Sutherland, Te Herenga Waka — Victoria University of Wellington

Graphic of Alpine Fault — The Alpine Fault marks the boundary between the Pacific and Australian plates in the South Island of New Zealand.
Author provided

The chances of New Zealand’s Alpine Fault rupturing in a damaging earthquake in the next 50 years are much higher than previously thought, according to our research, published today.

The 850km Alpine Fault runs along the mountainous spine of the South Island, marking the boundary where the Australian and Pacific tectonic plates meet and grind against each other, forcing up the Southern Alps. Over the past 4,000 years, it has ruptured more than 20 times, on average around every 250 years.

Alpine Fault earthquakes are recorded in lake sediment deposits.

The last major earthquake on the Alpine Fault was in 1717. It shunted land horizontally by eight metres and uplifted the mountains a couple of metres. Large earthquakes on the fault tend to propagate uninhibited for hundreds of kilometres.

Until now, scientists thought the risk of a major earthquake in the next 50 years was about 30%. But our analysis of data from 20 previous earthquakes along 350 kilometres of the fault shows the probability of that earthquake occurring before 2068 is about 75%. We also calculated an 82% chance the earthquake will be of magnitude 8 or higher.

Alpine Fault earthquakes in space and time

From space, the fault appears like a straight line on the western side of the Southern Alps. But there are variations in the fault’s geometry (its orientation and the angle it dips into Earth’s crust) and the rate at which the two plates slip past each other.

These differences separate the fault into different segments. We thought the boundaries between these segments might be important for stopping earthquake ruptures, but we didn’t appreciate how important until now.

We examined evidence from 20 previous Alpine Fault ruptures recorded in sediments in four lakes and two swamps on the west coast of the South Island over the past 4,000 years. From this evidence, we built one of the most complete earthquake records of its kind.

Once we analysed and dated the sediments from lakes near the Alpine Fault, we were able to see new patterns in the distribution of earthquakes along the fault. One of our findings is a curious “earthquake gate” at the boundary between the fault’s south western and central segments. It appears to determine how large an Alpine Fault earthquake gets.

Some ruptures stop at the gate and produce major earthquakes in the magnitude 7 range. Ruptures that pass through the gate grow into great earthquakes of magnitude 8 or more. This pattern of stopping or letting ruptures pass through tends to occur in sequences, producing phases of major or great earthquakes through time.

Forecasting the next Alpine Fault earthquake

From the record of past earthquakes it is possible to forecast the likelihood of a future earthquake (i.e. a 75% chance the fault will rupture in the next 50 years). But from these data alone it is not possible to estimate the magnitude of the next event.

For this we used a physics-based model of how earthquakes behave and applied it to the Alpine Fault, testing it against data from earlier earthquake sequences. This is the first time we have been able to use past earthquake data that span multiple large earthquakes and are of sufficient quality to allow us to evaluate how such models could be used in forecasting.

The physics-based model simulated Alpine Fault earthquake behaviour when we included the variations in fault geometry that define the different fault segments. When the simulation is combined with our record of past behaviour it is possible to estimate the magnitude of the next earthquake.

The Alpine Fault earthquake record shows the past three earthquakes ruptured through the earthquake gate and produced great (magnitude 8 or higher) earthquakes. Our simulations show that if three earthquakes passed through the gate, the next one is also likely to go through.

This means we’d expect the next earthquake to be similar to the last one in 1717, which ruptured along about 380km of the fault and had an estimated magnitude 8.1.

Our findings do not change the fact the Alpine Fault has always been and will continue to be hazardous. But now we can say the next earthquake will likely happen in the next 50 years.

We need to move beyond planning the immediate response to the next event, which has been done well through the Alpine Fault Magnitude 8 (AF8) programme, to thinking about how we make decisions about future investment to improve infrastructure and community preparedness.

Jamie Howarth, Senior lecturer, Te Herenga Waka — Victoria University of Wellington and Rupert Sutherland, Professor of tectonics and geophysics, Te Herenga Waka — Victoria University of Wellington

This article is republished from The Conversation under a Creative Commons license. Read the original article.

I walked 1,200km in the outback to track huge lizards. Here’s why

Sophie Cross, Curtin University

In 2017 and 2018 I walked the equivalent of 28 marathons in the scorching Western Australian outback. Why, you ask? To assess how some of Australia’s largest lizard species interact with restored mines.

As part of my PhD research, I hiked in often extreme heat on a mine site in WA’s sparsely populated Mid West region. My fieldwork was both physically and mentally demanding, as I spent many hours each day walking through the bush looking for signs of monitor lizards.

Being in a remote location and mostly alone, I had plenty of time to ponder the wisdom of my career choice, particularly on days when temperatures exceeded 40℃ and not even the lizards ventured from their homes.

Pushing through these mental challenges was difficult at times, but my work has provided me with some of my most rewarding experiences. And what I discovered may be crucial for restoring habitats destroyed by mining.

Restoring abandoned mines

Habitat loss is a leading cause of biodiversity loss worldwide. Although mining typically has a smaller environmental footprint than other major industries such as agriculture or urbanisation, roughly 75% of active mines are on land with high conservation value.

There are around 60,000 abandoned mines in Australia, but very few of them have been officially closed. How to restore them is a growing public policy problem.

Sophie Cross walked more than 1,200km and tracked a young-adult perentie to find out whether they were using a restored mining area.
Author provided

Recovering biodiversity can be an exceptionally challenging task. Animals are vital to healthy ecosystems, yet little is understood about how animals respond to restored landscapes.

In particular, reptiles are often overlooked in assessments of restoration progress, despite playing key roles in Australian ecosystems.

Do animals return to restored habitats?

I wanted to know whether restored habitats properly support the return of animals, or whether animals are only using these areas opportunistically or, worse still, avoiding them completely.

To study how reptiles behave in restored mining areas, I hand-caught and tracked a young adult perentie. The perentie is Australia’s largest lizard species, growing to around 2.5m in length, and is an apex predator in arid parts of the country.

I tracked the lizard for three weeks to determine whether it was using the restored area, before the tracker fell off during mating.

The tracking device revealed how the perentie navigated a restored mine, before it fell off during mating.
Author provided

Previous methods of tracking assume the animal used all locations equally. But I used a new method that measures both the frequency with which animals visit particular places, and the amount of time they spend there. This provided a valuable opportunity to assess how effective restoration efforts have been in getting animals to return.

Restoration needs more work

My research, published this week in the Australian Journal of Zoology, shows that while the perentie did visit the restored mine, it was very selective about which areas it visited, and avoided some places entirely. The lizard went on short foraging trips in the restored mine area, but regularly returned to refuge areas such as hollow logs.

The method used GPS and a VHF tracking antenna to follow the perentie.
Author provided

This is because hot, open landscapes with minimal refuges present high risks for reptiles, which rely on an abundance of coverage to regulate their body temperature and to avoid predators. Such costs may make these areas unfavourable to reptiles and limit their return to restored landscapes.

In comparison, undisturbed vegetation supported longer foraging trips and slower movement, without the need to return to a refuge area. Unfortunately, areas undergoing restoration often require exceptionally long time-periods for vegetation to resemble the pre-disturbed landscape.

How can we help reptiles move back into restored areas?

Restored landscapes often lack key resources necessary for the survival of reptiles. As vegetation can require a long time to reestablish, returning fauna refuges like hollow logs and fauna refuge piles (composed of mounds of sand, logs, and branches) could be crucial to aiding in the return of animal populations.

My research team and I have called for animals to be considered to a greater extent in assessments of restoration success. In the face of increasing rates of habitat destruction, we need to understand how animals respond to habitat change and restoration.

Failing to do so risks leaving a legacy of unsustainable ecosystems and a lack of biodiversity.

Sophie Cross, PhD candidate, Curtin University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Academia can help humans and large carnivores coexist

In Romania, wolves live in the same landscapes as shepherds.
Shutterstock

Euan Ritchie, Deakin University; Abi Vanak, University of KwaZulu-Natal; Benjamin Scheele, Australian National University; Laurentiu Rozylowicz, and Tibor Hartel

Bears, wolves, lions and other top predators have a long history of conflict with people – they can threaten our safety and kill livestock.

In our recent study, published in Conservation Biology, we outline how conventional conservation approaches are unlikely to lead to effective coexistence between humans and large carnivores in human-dominated landscapes.

This wicked problem encompasses public safety, agriculture, conservation, animal welfare, and more. Each facet is commonly managed by a different institution working in isolation – often failing to reflect the reality of our highly connected world.

Academia can help foster better institutional arrangements, especially in places like Romania, India and Brazil, where there are substantial populations of people and large carnivores in shared spaces.

In Romania, for instance, bears and wolves live in the same places used by shepherds and their livestock. Guardian dogs typically help protect livestock from being attacked.

Similarly, Australia’s own dingo occurs across agricultural and pastoral regions, with sentiments ranging from protected native species to disliked pest.

Why institutions fail carnivore-human relationships

From bears in Romania to dingoes in Australia, large carnivores are found in an array of places. This means they regularly affect the interests of a range of institutions, from agriculture to forestry.

But the current arrangements are poorly suited to facilitate a peaceful coexistence between humans and large carnivores.

Typically, institutions focus on a small subset of concerns. Forestry and agricultural sectors, for instance, may not feel responsible for large carnivore conservation because they are primarily interested in timber and agricultural production.

On the other hand, institutions for transport, energy and border security might be indifferent towards large carnivores. But they can negatively affect these animals if they put up barriers restricting predator movement and inappropriately handle roadkill.

These compartmentalised, and often conflicting, institutions are poorly suited to helping wildlife, especially when large carnivores, such as leopards, wolves and bears, live in human-dominated regions.

A role for academia

Academia has solutions to offer.

Most environment-related professionals, like foresters, wildlife managers and conservation biologists, are trained in a range of academic institutions. Unfortunately, they are often taught narrowly within their sector or discipline.

However, all these future professionals passing through the same institutions provides a great opportunity for a broad change in how we approach difficult conservation challenges and conflict with wildlife.

A leopard being rescued from a well in rural India, where the animals interact with locals regularly.
Photo credit: John Linnell

There are at least three ways in which academia could help address the challenges of human and large carnivore coexistence:

1. Break down the silos

Academic institutions need to create special centres to better support teaching and research across different disciplines.

Conservation – and, on a broader level, how humans should relate to the natural world – cannot be siloed away in wildlife management courses.

2. Broaden the view

We need to actively foster a broader perspective that does not see large carnivores as an “enemy”, while still safeguarding human life. This is a complex and multifaceted challenge.

By working across disciplines, universities have the chance to actively foster this broader perspective. This may seem like a nebulous point, but the collapse of species around the world has highlighted how ineffective our current approach to conservation is. We need to move beyond tinkering around the edges of our extinction crisis.

Conservation policy is already equipped to address individual targets such as regulating carnivore populations and legally protecting species. It is the larger aim of changing norms, challenging values and ensuring all these various institutions are pulling in the same direction that we need to tackle – a tactic called the “leverage points approach”.

3. Work outside the academy

Academia could support existing collaborations. When people with shared interests come together to pool knowledge and address a particular issue, we call it a community of practice. Academia can contribute to these communities by offering the skills and expertise of its graduates, but also broader social and industry connections (where required), knowledge sharing, collaborative research, education and technological innovation.

We need big carnivores and they need us

Large carnivores are critical for the health of ecosystems globally, and we need to provide them with enough space and tolerance to survive.

The ongoing controversy regarding the management of the dingo, Australia’s largest land-based predator (aside from humans), provides a perfect test case for this new approach to managing human-wildlife conflict.

If we can achieve more harmonious relations with the world’s top predators, many of the myriad other species that coexist with them are also likely to benefit from both better habitat management and conservation and the important ecological effects large carnivores can have, such as keeping herbivore and smaller predator numbers in check. This can be a positive step towards addressing Earth’s mass extinction crisis.

The authors would like to thank John Linnell, Senior Research Scientist at the Norwegian Institute for Nature Research, for his contribution to this article.

Euan Ritchie, Associate Professor in Wildlife Ecology and Conservation, Centre for Integrative Ecology, School of Life & Environmental Sciences, Deakin University; Abi Vanak, , University of KwaZulu-Natal; Benjamin Scheele, Research Fellow in Ecology, Australian National University; Laurentiu Rozylowicz, Center for Environmental Research and Impact Studies, University of Bucharest, and Tibor Hartel, Invited user

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Australia: Large Fish Species in Serious Decline

The link below is to an article reporting on the serious decline in large fish species across Australia.

For more visit:
https://www.theguardian.com/environment/2018/jun/05/australias-large-fish-species-declined-30-in-past-decade-study-says

From feral camels to ‘cocaine hippos’, large animals are rewilding the world

File 20170902 27513 hsa0io — Most of the world’s wild horses, such as the Australian brumby, are outside their historic native range.
Andrea Harvey

Erick Lundgren, University of Technology Sydney; Arian Wallach, University of Technology Sydney; Daniel Ramp, University of Technology Sydney, and William Ripple, Oregon State University

Throughout history, humans have taken plants and animals with them as they travelled the world. Those that survived the journey to establish populations in the diaspora have found new opportunities as they integrate into new ecosystems.

These immigrant populations have come to be regarded as “invaders” and “aliens” that threaten pristine nature. But for many species, migration may just be a way to survive the global extinction crisis.

In our recently published study, we found that one of the Earth’s most imperilled group of species is hanging on in part thanks to introduced populations.

Megafauna – plant-eating terrestrial mammals weighing more than 100kg – have established in new and unexpected places. These “feral” populations are rewilding the world with unique and fascinating ecological functions that had been lost for thousands of years.

Today’s world of giants is only a shadow of its former glory. Around 50,000 years ago, giant kangaroos, rhino-like diprotodons, and other unimaginable animals were lost from Australia.

Later, around 12,000 years ago, the last of the mammoths, glyptodonts, several species of horses and camels, house-sized ground sloths and other great beasts vanished from North America.

In New Zealand, a mere 800 years ago, a riot of giant flightless birds still grazed and browsed the landscape.

The loss of Earth’s largest terrestrial animals at the end of the Pleistocene was most likely caused by humans.

Sadly, even those large beasts that survived that collapse are now being lost, with 60% of today’s megafauna threatened with extinction. This threat is leading to international calls for urgent intervention to save the last of Earth’s giants.

A wilder world than we think

Formal conservation distribution maps show that much of Earth is empty of megafauna. But this is only a part of the picture.

Many megafauna are now found outside their historic native ranges. In fact, thanks to introduced populations, regional megafauna species richness is substantially higher today than at any other time during the past 10,000 years.

Megafauna have expanded beyond their historic native range to rewild the world. Number of megafauna per region, in their ‘native’ range only (a) and in their full range (b)
Modified and reproduced from Lundgren et al. 2017

Worldwide introductions have increased the number of megafauna by 11% in Africa and Asia, by 33% in Europe, by 57% in North America, by 62% in South America, and by 100% in Australia.

Australia lost all of its native megafauna tens of thousands of years ago, but today has eight introduced megafauna species, including the world’s only wild population of dromedary camels.

Australia lost all of its native megafauna tens of thousands of years ago, but is now home to eight introduced species, including the world’s only population of wild dromedary camels. Remote camera trap footage from our research program shows wild brumbies, wild donkeys and wild camels sharing water sources with Australian dingoes, emus and bustards in the deserts of South Australia.

These immigrant megafauna have found critical sanctuary. Overall, 64% of introduced megafauna species are either threatened, extinct, or declining in their native ranges.

Some megafauna have survived thanks to domestication and subsequent “feralisation”, forming a bridge between the wild pre-agricultural landscapes of the early Holocene almost 10,000 years ago, to the wild post-industrial ecosystems of the Anthropocene today.

Wild cattle, for example, are descendants of the extinct aurochs. Meanwhile, the wild camels of Australia have brought back a species extinct in the wild for thousands of years. Likewise, the vast majority of the world’s wild horses and wild donkeys are feral.

There have been global calls to rewild the world, but rewilding has already been happening, often with little intention and in unexpected ways.

A small population of wild hippopotamuses has recently established in South America. The nicknamed “cocaine hippos” are the offspring of animals who escaped the abandoned hacienda of Colombian drug lord Pablo Escobar.

Colombia’s growing ‘cocaine hippo’ population is descended from animals kept at Pablo Escobar’s hacienda.

By insisting that only idealised pre-human ecosystems are worth conserving, we overlook the fact that these emerging new forms of wilderness are not only common but critical to the survival of many existing ecosystems.

Vital functions

Megafauna are Earth’s tree-breakers, wood-eaters, hole-diggers, trailblazers, wallowers, nutrient-movers, and seed-carriers. By consuming coarse, fibrous plant matter they drive nutrient cycles that enrich soils, restructure plant communities, and help other species to survive.

The wide wanderings of megafauna move nutrients uphill that would otherwise wash downstream and into the oceans. These animals can be thought of as “nutrient pumps” that help maintain soil fertility. Megafauna also sustain communities of scavengers and predators.

In North America, we have found that introduced wild donkeys, locally known as “burros”, dig wells more than a metre deep to reach groundwater. At least 31 species use these wells, and in certain conditions they become nurseries for germinating trees.

Introduced wild donkeys (burros) are engineering the Sonoran Desert, United States.

The removal of donkeys and other introduced megafauna to protect desert springs in North America and Australia seems to have led to an exuberant growth of wetland vegetation that constricted open water habitat, dried some springs, and ultimately resulted in the extinction of native fish. Ironically, land managers now simulate megafauna by manually removing vegetation.

It is likely that introduced megafauna are doing much more that remains unknown because we have yet to accept these organisms as having ecological value.

Living in a feral world

Like any other species, the presence of megafauna benefits some species while challenging others. Introduced megafauna can put huge pressure on plant communities, but this is also true of native megafauna.

Whether we consider the ecological roles of introduced species like burros and brumbies as desirable or not depends primarily on our own values. But one thing is certain: no species operates in isolation.

Although megafauna are very large, predators can have significant influence on them. In Australia, dingo packs act cooperatively to hunt wild donkeys, wild horses, wild water buffalo and wild boar. In North America, mountain lions have been shown to limit populations of wild horses in some areas of Nevada.

Visions of protected dingoes hunting introduced donkeys and Sambar deer in Australia, or protected wolves hunting introduced Oryx and horses in the American West, can give us a new perspective on conserving both native and introduced species.

Nature doesn’t stand still. Dispensing with visions of historic wilderness, and the associated brutal measures usually applied to enforce those ideals, and focusing on the wilderness that exists is both pragmatic and optimistic.

After all, in this age of mass extinction, are not all species worth conserving?

This research will be presented at the 2017 International Compassionate Conservation Conference in Sydney.

Erick Lundgren, PhD Student, Centre for Compassionate Conservation, University of Technology Sydney; Arian Wallach, Chancellor’s Postdoctoral Research Fellow, Centre for Compassionate Conservation, University of Technology Sydney; Daniel Ramp, Associate Professor and Director, Centre for Compassionate Conservation, University of Technology Sydney, and William Ripple, Distinguished Professor and Director, Trophic Cascades Program, Oregon State University

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

Why Do Red Pandas Have Large Tails?

World’s Largest Spiders

Africa: Sahara Desert Wildlife

The link below is to an article reporting on the decline of large animals in the Sahara Desert region of Africa.

For more visit:
http://news.mongabay.com/2013/1203-hance-sahara-big-animal-crisis.html

Freshwater Under The Seabed

The link below is to an article that reports on the large quantities of freshwater in the ocean – well, under the ocean to be exact.

For more visit:
http://www.npr.org/blogs/thetwo-way/2013/12/11/250308953/scientists-map-vast-reserves-of-freshwater-under-the-seabed

Skyonic to soon start construction on large carbon capture plant in Texas

Gigaom

Startup Skyonic — which develops technology that turns carbon emissions from power plants and factories into substances like baking soda — plans to start construction on the largest commercial carbon capture plant in the U.S. next week. The plant will be built at a cement factory in San Antonio, Texas, and will capture carbon emissions, acid gases and heavy metals from the flue of the cement factory.

Skyonic’s technology is based around turning factory and plant emissions into usable products, like baking soda, hydrochloric acid and bleach. So the plant in Texas is expecting to pay off the investment — and turn a profit — by selling the products to buyers. The plant expects to convert 75,000 tons of CO₂ into products, and offset another 225,000 tons per year.

The startup is announcing the start of construction during an event next week at the plant, where a local judge…

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Kevin's Walk on the Wild Side

Environment, Wildlife and Wilderness – Articles and News

Tag Archives for large

NZ’s next large Alpine Fault quake is likely coming sooner than we thought, study shows

Alpine Fault earthquakes in space and time

Forecasting the next Alpine Fault earthquake

I walked 1,200km in the outback to track huge lizards. Here’s why

Restoring abandoned mines

Do animals return to restored habitats?

Restoration needs more work

How can we help reptiles move back into restored areas?

Academia can help humans and large carnivores coexist

Why institutions fail carnivore-human relationships