The New Nature

  About the Book

  Winner of the NIB Waverley Award for Literature.

  Nature isn’t confined to the wilderness, it lives in out cities and gardens, exploiting everything we do, forging new connections with us. Endangered species are turning up in industrial zones. In our forests, certain native creatures have become pests and are now a force to be reckoned with. Sheep are being kept in some national parks to protect rare birds and plants. We need to know why.

  In so explaining, Tim Low’s groundbreaking book will change your view of nature. This edition has a new introduction that shows how important it is to understand the relationships we have with nature today.

  ‘Low argues with a novelist’s zeal that the line we draw between “good, pure, harmonious nature and evil, selfish, destructive humans” is as artificial as the blue plastic that bower birds seek out to decorate their forest boudoirs.’ TIME

  ‘A welcome dose of reality.’ THE AGE

  ‘[Tim Low] makes a strong case ... for the need for a new understanding of the natural world. And he does so in a popular style that is accessible to the non-scientist.’ SYDNEY MORNING HERALD

  Preface to the 2017 Edition

  Introduction

  PART ONE NATURE AND US

  1  Exploited by Nature – Nature Using Us

  2  Endangered Weeds – Rarities Lurk Among Us

  3  Away from Wilderness – Questioning an Unhelpful Idea

  4  Ecosystem Engineers – Animals Alter Landscapes

  5  The Ecology of Sewage – Wildlife Wants Our Wastes

  6  Structure for Nature – Animals Exploit Our Structures

  7  Nature Needs Weeds – Weeds and Crops Suit Wildlife

  8  Urban Ecology – Life in Cities and Farms

  PART TWO CHANGING PLACES

  9  On the Move – Animals Expand Ranges

  10  Foreign Exchange – International Spread

  11  Hidden Hitchhikers – Dispersal by Vehicle

  12  Tales of Transportation – Relocating Wildlife

  13  Noble Arks – Stocking National Parks

  14  Fun with Fish – Fish Stockers Run Amok

  15  Pardon My Garden – Native Gardens Spawn Weeds

  PART THREE CONFLICTS

  16  Bad Birds – Native Birds as Eco-Threats

  17  What Kangaroos Do – Overgrazing in Reserves

  18  To Kill a Tree – Koalas and other Tree-Killers

  19  Vegetation Wars – Habitats in Turmoil

  20  Gene Scene – Mixing Gene Pools

  PART FOUR RESOLUTIONS

  21  Wild Strife in the Garden – Urban Conservation Myths

  22  Grazing and Culling for Conservation – Ironies of Modern Management

  23  Forward to Nature – Living with Wildness

  Appendices

  I  Errant Native Plants Around Cities

  II  Australian Animals as Conservation Threats

  Source Notes

  Bibliography

  For Kory

  Beauty and purity are qualities we identify with nature, which encourage us to care for it. But if we are too sold on nature’s perfection, our thinking about other species will be unrealistic, leaving us blind to some serious environmental problems. These need our attention, which is why, more than a decade ago, I wrote this book. To some extent, the nature of the book ended up a surprise to me. I never expected to be celebrating sewage or criticising wildlife-friendly gardening.

  We would do well at times to consider ourselves part of nature rather than always on the outside. This can be satisfying, and at the same time help us understand more of what we see. Native animals don’t have any concept of ‘unnatural’, so they don’t necessarily recoil from humanised landscapes. The native animals in our cities are not there, most of the time, as refugees from habitat loss, but because cities meet their needs. We shouldn’t presume that nature, merely by definition, wants to be natural. The words ‘nature’, ‘natural’ and ‘wilderness’ can end up misleading us about the natural world. The environments we create are often rich in resources for those that can exploit them. It might seem heretical to say this, but cities and farms provide some species with better habitat than anything natural, which they show by living in high densities. Like humans, brushtail possums, rainbow lorikeets and bluetongue lizards reach their peak densities in cities.

  One reason it is beneficial to focus on this is that many Australians are dismissive of any environmental crisis because they see parrots and other bold native birds thriving in cities around them. When the conservation message sounds too much like ‘nature is suffering’, it is easily shrugged off as exaggeration. To bring more Australians on board, the environment movement needs to talk more about winners – to ensure that its messages about losers are considered credible.

  Winners also matter because some of them are ecologically powerful. Instances keep emerging of thriving native animals doing harm to endangered species or habitats. The crown-of-thorns starfish plagues stripping bare the Great Barrier Reef are an infamous example, but there are many others, and more can be expected in future. We cannot care for the environment properly unless we acknowledge that native species, responding to us, represent one of the big conservation issues in Australia.

  In the fifteen years since I wrote this book, climate change has become a central issue and an ideal test of what I wrote. If there are species that can profit from anything we do, we would expect to see climate change winners emerging as a new conservation concern. I had a chance to assess this when, as a result of this book, I was invited to join the federal environment minister’s Biological Diversity Advisory Committee. In 2006 I ran a workshop in Canberra on climate change and invasive species, which included native animals, plants and diseases. Striking stories emerged.

  In Tasmania the long-spined sea urchin (Centrostephanus rodgersi) is turning lushly productive sea beds into ‘barrens’ with limited marine life by overgrazing the seaweeds. Along with various fishes, it was conveyed south from New South Wales by a warming of the East Australian Current. The Institute for Marine and Antarctic Studies rates it ‘a very significant threat’ to Tasmania’s shallow reef systems. Overfishing of rock lobsters, the main predators of urchins, is part of this problem.

  In the Australian Alps, kookaburras reaching higher altitudes are preying on alpine lizards that fail to regard them as dangerous. The Australian Department of the Environment lists them as a problem for the endangered Guthega skink (Liopholis guthega). Swamp wallabies and red-necked wallabies also moving to higher altitudes threaten the future of alpine herbfields. Snow gums are not (yet) creeping upslope, but when they do they will displace alpine plants. Experiments around the world show that alpine shrubs and herbs can tolerate high temperatures, but they will lose out from trees that shade them out (and from drier soil). Many species on mountains have their lower altitudinal limits set, not by temperatures directly, but by other species that limit them wherever temperatures are high enough. The problems of climate change will very often come in the form of native species causing harm. The evidence for this is compelling: in Australia very few species have yet moved in response to warming but several are already problematic.

  However, when climate change is talked about, the migration of species southwards and upslope is nearly always portrayed as desirable. Most of the time it will be, but the exceptions show how important it is to understand the problems native species can cause. In chapters 11 and 13, I mention the downsides of lyrebirds and mucor fungus establishing in Tasmania, as well as pandanus planthoppers in southern Queensland. Their spread south had little (if anything) to do with climate change but shows that species movement (in any direction and for any reason) can bring pr
oblems. As for humans deliberately moving species to help them survive climate change, I am pleased to say there is recognition in Australia that risk assessments should be conducted first.

  I am reluctant to go straight to another bleak story, but I must mention one of the big surprises of the past decade – the evidence that the sugar gliders taken to Tasmania in the 1830s (chapter 12) are proving a disaster for endangered swift parrots and orange-bellied parrots (chapter 23). A recent study with motion-triggered cameras showed that these cute little gliders overpowered and ate the female bird in twenty of the seventy monitored nests. Warning of imminent extinction for the parrots, researchers at the Australian National University launched a crowd-funding appeal to buy a thousand glider-proof nest boxes. Sugar gliders are well known animals, but before camera traps came into use they weren’t known to eat birds or their eggs. Had climate change justified moving sugar gliders south, anyone conducting a risk assessment a mere decade ago would not have predicted this outcome. It shows how very careful we must be about translocating species. I am not saying that species should never be moved, but that anyone contemplating this should be very well-informed about past problems. The glider situation turns out to be complicated, with camera traps revealing that sugar gliders and squirrel gliders are preying on endangered regent honeyeaters in Victoria as well.

  Before I leave the topic of climate change I should mention that it is sometimes invoked, without enough care, to explain any southward spread in Australia. In 2005, rising temperatures were proposed as the reason that flying foxes moved into Melbourne, instead of the food trees I mention in chapter 8. This claim attracted criticism in two academic papers – one pointing out that the shift south was too rapid to fit climate change, the other emphasising the same food trees I had. Those wanting to understand climate change should consider all the reasons that species move, rather than focusing on just one. In Australia so far, habitat changes (including dams) seem to explain more shifts than climate change, at least on land. The climate certainly doesn’t explain why Cootamundra wattle (Acacia baileyana), coast tea tree (Leptospermum laevigatum) and the long-billed corella have spread north by large distances.

  Besides providing some updates, this new preface is my chance to mention a few mistakes I have found upon rereading the text. My suggestion that most whipbirds depend on lantana is probably exaggerated by my southern-Queensland perspective. There is ample research showing that gardens with currawongs tend to have fewer small birds than gardens without (see my book Where Song Began), but my depiction of them as super-efficient predators is overdone. The burgan groves I mention, while continuing to have a downside, are proving to have some value as bird habitat.

  I have also rewritten the ending of the book to update the information about flying foxes. To bring other chapters up to date, some points are made here. The Christmas Island pipistrelle (chapter 6) and Bramble Cay melomys (chapter 1) are now extinct. So too, it seems, is the white-chested white-eye (chapter 10). Numbers of the endangered orange-bellied parrot (chapter 2) have fallen below seventy and, by the time you read this, the species may exist only in captivity. The barred bandicoots in Hamilton (chapter 2) have not survived, although efforts continue to return them to the wild in Victoria, albeit to life behind fences. The endangered forty-spotted pardalote faces less of a threat from noisy miners than it does from a native parasitic fly (Passeromyia longicornis; a possible beneficiary of climate change) killing its chicks. Some of the threatened plants I mentioned have had their listings changed. There are many other ‘endangered weeds’ I might have mentioned, such as Norseman pea (Daviesia microcarpa), thought to be extinct until a roadside was graded and plants appeared. Endangered animals I would mention today include Hanley’s river snail (Notopala hanleyi), now entirely confined to a few underground irrigation pipes, and the Condamine earless dragon (Tympanocryptis condaminensis) found largely in crops of cotton, sorghum, wheat, maize and sunflowers.

  In 2013–14, close to seven hundred starving koalas were euthanased in the Cape Otway area, bearing out the prediction made of a disaster looming (chapter 18). The ABC News reported hundreds of acres of dead trees and the smell of death. Native plant diseases that warrant a mention (because they are increasing) include myrtle wilt – on myrtle beeches – and banksia cankers (Zythiostroma). Surprising as it may seem, the un-named species of rodent mentioned in chapter 2 still has no name.

  There is some good news. Lord Howe Island now has proper quarantine, the endangered velvety peppercress (chapter 2) is known on at least nine sites (up from the two I mentioned) and banded stilts (chapter 4) are not doing badly enough to become endangered. Forestry Tasmania is undertaking research to limit pollen moving between eucalypt plantations and wild trees, unlike in Queensland, where foresters are breeding hybrid spotted gums (Corymbia citriodora) and cadaghi (Corymbia torelliana) with little regard for the impacts on native eucalypts.

  Some ecologists have proposed that ecosystems made up of stable mixtures of native and introduced species should be valued as much as intact habitats. While I agree that novel ecosystems, as they are called, are now vital to saving some species from extinction, I abhor any suggestion that they match native ecosystems in value.

  In this book, I criticise the notion of wilderness for inhibiting us from seeing what is happening. My problem is with the romance attached to the idea, not with the value placed on intact habitats. We need these more than ever, not only because they conserve vast numbers of species, but because they help us set management goals. Across much of Australia the land needs repair and ‘wilderness areas’ are points of reference to aim for in landscape rehabilitation. Almost by definition, they preserve information about how Australia looked before it was degraded and that is information we cannot do without.

  I recommend positioning ourselves as part of nature as a thought exercise, but we can’t always adopt that stance. The bulldozing of forests can’t be condoned as a natural process, and nor should the spread of weedy garden plants into forests. Sometimes it is useful to think of ourselves as unique, while other times it is more beneficial to think of ourselves as one animal among many.

  This book was written as a companion of sorts to Feral Future (Penguin, 1999), which looked at introduced pests. I wrote it using everyday language while remaining biologically sound. Although I use words scientists avoid (‘nature’, ‘winners’), I operate within an ecological paradigm. I am a practising biologist.

  Most of my stories are backed up by scientific references listed in the Source Notes and Bibliography. The Source Notes contain extra information backing up statements in the main text. For ease of reading, not every author is mentioned within the text. Virtually everyone cited is a biologist unless otherwise stated. On joint papers I sometimes say ‘Jones and colleagues’. My aim is not to downplay junior authors but to keep the sentences flowing. I owe a great debt to Australia’s biological community for producing so much excellent work to draw upon, and apologise unreservedly to all those who should have been mentioned in the main text but ended up in the Source Notes. No-one agrees about when Aborigines reached Australia; I have used 50 000 years because it’s a popular figure, not because I’m sure it’s right.

  A great many people helped. Most of you are mentioned in the text, others in the Source Notes. I am grateful to all of you, without implying any complicity in the conclusions drawn. I owe a great debt to Carol Booth for passing on many important articles on conservation and philosophy and for debating ‘nature’. Geoff Carr alerted me to many Victorian examples and gave freely of his expertise. Doug Laing took me around Canberra and provided useful information. I am also grateful to Owen Foley, Tricia Worthington, Julia Playford, Jack Craw, Steve Harris, Stephen Page, Jennie Dowling, Kory Horwood and Katelou Pappatheodoru.

  At Penguin Wendy Elliot was a delightful editor, followed in the late stages by the very helpful Meredith Rose, and Clare Forster was my able publisher.

  I don’t believe in final answers, only unfold
ing stories. This is one such.

  Tim Low

  Edworthy, A. (2015), ‘What’s Killing the Endangered Forty-spotted Pardalote?’, Tasmanian Geographic 31, www.tasmaniangeographic.com/whats-killing-pardalote/

  Heinsohn, R., Webb, M., Lacy, R., et al. (2015), ‘A severe predator-induced population decline predicted for endangered, migratory swift parrots (Lathamus discolor)’, Biological Conservation 186: 75–82.

  Ives, C., Lentini, P., Threlfall, C., et al. (2016), ‘Cities are hotspots for threatened species’, Global Ecology and Biogeography 25(1): 117–126.

  Johnson, C., Banks, S., Barrett, N., et al. (2011), ‘Climate change cascades: Shifts in oceanography, species’ ranges and subtidal marine community dynamics in eastern Tasmania’, Journal of Experimental Marine Biology and Ecology 400(1–2) SI: 17–32.

  Low, T. (2008), Climate Change and Invasive Species: A Review of Interactions, Biological Diversity Advisory Committee, Canberra.

  Parris K. & Hazell D. (2005), ‘Biotic effects of climate change in urban environments: the case of the Grey-headed Flying-fox (Pteropus poliocephalus) in Melbourne’, Biological Conservation 124(2): 267–76.

  Roberts, B., Catterall, C., Eby, P., et al. (2012), ‘Latitudinal range shifts in Australian flying-foxes: A re-evaluation’, Austral Ecology 37(1): 12–22.

  Sheldon, F. and Walker, K., (1993), ‘Pipelines as a refuge for freshwater snails’, Regulated Rivers: Research & Management 8: 295–299.

  Starr, C., & Leung, L. (2006), ‘Habitat use by the Darling Downs population of the grassland earless dragon’, Journal of Wildlife Management 70(4): 897–903.

  van der Ree, R., McDonnell, M., Temby, I., Nelson, J. & Whittingham, E. (2006), ‘The establishment and dynamics of a recently established urban camp of Pteropus poliocephalus outside their geographic range’, Journal of Zoology 268: 177–85.