The New Nature Read online

  I first saw cowbirds at a grain silo near New Orleans. I stared in awe at the seething mass of shiny black birds by the road. Here, but for parasitism, would have been colourful cardinals, orioles, warblers, phoebes, juncos, gnatcatchers, and more. Brown-headed cowbirds don’t even belong in New Orleans. Their range originally centred on the Great Plains well to the north, where they followed bison herds. But as buffalo fell before bullets, cowbirds learned to travel instead with the covered wagons of the pioneers, reaching new pastures on the way. California was colonised in the 1890s and British Columbia by 1955. Most of the United States is now cowbird country, coast to coast. Vagrants have even reached Britain and Norway. Cowbirds have done more to expand their range than even Australia’s crested pigeon, and new cowbirds are invading. The shiny cowbird island-hopped across the West Indies from South America, arriving in the US in 1985; the bronzed cowbird is spreading north from Mexico. The cowbird invasion is big news in the US and a blight on Latin America as well. Where Amazon rainforests crash under the axe, shiny cowbirds colonise new farms and fields. They do extremely well on new forest edges where local birds are parasite-naïve.

  I called this chapter ‘Bad Birds’, but only to attract attention. Animals implicated in conflicts still deserve our affection and respect. Cam Beardsall stopped choughs exterminating orchids, yet never lost his love for them. ‘They’re such good birds,’ he told me. ‘Amusing, intelligent and socially minded. They’re not that different from humans.’ True, and like humans they can wreak ruin on other species. They have much to teach us about our own ecological role on earth.

  1  Only the Kangaroo Island subspecies is endangered, not the species overall.

  2  Possums and rats are guided by smell and would not attack clay eggs.

  ‘To eat is to appropriate by destruction.’

  Jean-Paul Sartre, Doing and Having

  Conservation is one of those modern concerns that dates back to early convict days. Climate change emerged as a worry as far back as 1795, when magistrate Richard Atkins feared the weather was changing ‘in consequence of the country opening so fast’. Victoria set land aside ‘for climatic reasons’ in 1890. Controls over tree clearing go back to 1803, when Sydney’s Governor King, worried by worsening floods, forbade clearing of cedars on private land abutting the Hawkesbury River. The slaughter of seals also aroused concerns by this time. Extinction, deforestation, pollution and erosion all attracted criticism a hundred years ago. Sydney bookseller J.W.R. Clarke claimed in 1898 to have written ‘nearly one thousand letters to the Australian press’ about the need to preserve wildlife.

  Around the townships anything that moved in early colonial days was shot, which led to fears as early as 1822 that extinction loomed for kangaroos. In 1832 naturalist George Bennett advocated domesticating them, along with emus and lyrebirds, ‘before, by extermination, they are lost to us for ever’. Four years later Charles Darwin, visiting Australia on the Beagle, said of kangaroos that ‘their doom is fixed’. John Gould urged their legal protection ‘ere it be too late’.

  Concerns about extinction helped spawn in 1888 what was probably Australia’s first green group: the Flora and Fauna Protection Committee of the Field Naturalists’ Society of South Australia. Arthur Robin, speaking at the group’s founding in Adelaide, warned that ‘kangaroos, of which thirty years ago there were very many thousands, have now nearly disappeared for hundreds of miles from the city’. By 1914 the committee held ‘grave fears’ that the kangaroo was already extinct.

  Yet South Australia today supports many more kangaroos than people. Numbers exceed 3 million, compared to 1.2 million humans.1 Not only are they a problem on farms, they are also degrading nature reserves. According to national parks officer Peter Alexander, ‘virtually every park in South Australia has a kangaroo problem’. I saw what Peter meant when I visited Parra Wirra Recreation Park north of Adelaide. The grass was clipped down to bowling-green height. Before I could sit on a knoll for lunch, I had to rake away all the kangaroo do; there wasn’t a bum-sized patch of clean ground around. To reach the knoll, I had driven past a kangaroo-exclusion plot with plants thriving inside. Fenced enclosures that keep out rabbits only, and others that exclude both rabbits and kangaroos, show the harm these animals do. Kangaroos hit some plants that rabbits avoid, such as chocolate lilies, vanilla lilies and pink-eyed susans. They behead orchids by biting off their buds. And by creating short grazing turfs (called ‘wallaby lawns’) they benefit rabbits.

  Kangaroos pose a serious challenge for Australia. They proliferate around paddocks and dams – in other words, almost everywhere. At Tidbinbilla a density of 367 kangaroos per square kilometre was once recorded, an unbelievable burden on the land. Aborigines, dingoes and droughts no longer limit their numbers. As Rolf Boldrewood noted in 1884, ‘the wild hound did good service in keeping down the kangaroo, which, after his extinction, proved a much more expensive and formidable antagonist’. Remade to suit cattle and sheep, Australia suits kangaroos too. They do best in fragmented landscapes where forests and pastures abut, where stock have created stable pastures and where dingoes no longer roam. South Australia, Victoria, and inland New South Wales are worst affected. Problems are caused by eastern and western grey kangaroos, red kangaroos and wallaroos (or euros). Wallabies also cause strife in many situations. Kangaroos and wallabies are together called macropods, and Australia has a vast and complicated macropod problem.

  Hattah-Kulkyne National Park in western Victoria is infamous for its roo woes. This new park by the Murray River was a grazing property for a long time. Trees had been cleared, and numbers of western grey kangaroos were excessive. By the 1980s roos and rabbits were eroding dunes, degrading native pasture and killing seedlings and herbs. Weeds were thriving. Seven endangered plants were threatened. ‘It broke your heart to see the blow-out dunes that were not regenerating,’ said Stephen Page, a regular visitor.

  Rangers targeted rabbits first. A big paddock (5700 hectares) was fenced off and most of the bunnies removed. But the paddock also carried 1500 roos, and four years later it hadn’t improved. Rangers then evicted kangaroos from smaller plots within the paddock – and lo, native plants returned. Native speargrasses and legumes spread a soft blanket over the naked earth. Wattles and cypress pines came back. The next goal was to reduce kangaroo numbers across the whole paddock. After an attempt at mustering failed, the rangers turned to culling. In 1984 almost 800 kangaroos were shot and buried in pits. A public outcry ensued.

  National Parks officer David Cheal explained the thinking behind the cull: ‘In our naivety we were working on the assumption that it was just another control action, like a controlled burn. Then when the outcry came we realised we’ve got to justify this to people. It was a decision that was taken extremely reluctantly, not with guns blazing. We were watching plant species disappear and whole plant communities disappear. We weren’t saying that kangaroos were the problem but we were saying that kangaroos were stopping the problem being solved . . . Some people have the curious belief that a native animal, almost by definition, cannot do something harmful to the environment. It’s almost a theological statement to some people. But if you are a rare plant it doesn’t matter to you if you are being eaten by a kangaroo or a sheep or a rabbit.’

  I see ‘balance of nature’ as the overarching theological doctrine here, the one implying that native species must live together harmoniously. After a long process of consultation at Hattah-Kulkyne, a larger cull began. Over four years, shooters took out 15000 roos. When more trees grow they will shade out some grass and help keep numbers down. ‘There has already been a dramatic response,’ David said. ‘Perennial grasses now dominate the landscape instead of bare dunes.’ Emu numbers have multiplied. The grass Triraphis mollis, once rare, now thrives.

  ‘The kangaroo problem tends not to be well documented,’ said the Victorian Government’s Adrian Moorrees, referring to conservation issues. ‘People tend to look at all the exotics as the “nasties”. They fo
cus on rabbits and other exotics, including domestic stock.’ The impact of native grazing is overlooked. ‘In the parts of the state where they are a problem they are probably up towards the top of the list – in the top three – as a threatening process,’ Adrian went on. ‘They can be the worst threat, particularly in combination with fire.’ Plants that need fire to germinate suffer when kangaroos eat all the fuel. Kangaroos pose problems in many inland national parks. In the Flinders Ranges, South Australia, wallaroos are the problem species. When sheep and cattle were taken off the land, wallaroos took over, feeding on the pastures and stalling regeneration by shrubs and trees.

  Kangaroos love eating (and trampling) orchids. The sand-hill spider-orchid (Caladenia arenaria), a dainty plant with long pink petals, is one of several species at risk from their attentions. Only four populations survive, the largest in Lonesome Pine State Forest in western New South Wales. Hungry, clumsy kangaroos are ruining the place: ‘There’s kangaroo shit in there everywhere and every square metre has got a kangaroo footprint in it,’ Geoff Carr told me. ‘There’s a huge amount of mechanical damage – trampling. You see bloody kangaroo highways going in every direction. These soft-footed animals are not so benign as some people might think.’

  Kangaroos also add to the woes of declining birds. ‘There’s a major wave of extinctions of woodland birds going on in southern Australia,’ conservation campaigner Barry Traill told me, ‘and although gross clearing of land is the major cause, it appears that overgrazing by roos is adding to the problem, along with weeds, stock grazing, rabbits and firewood collection’. By stripping bare the understorey, roos ruin habitat for babblers, robins and wrens. The white-browed treecreeper is in trouble, the federal government says, because woodland remnants heavily grazed by stock and roos aren’t reviving.

  Kangaroos prove especially destructive when enclosed in small reserves. Woodlands Historic Park on the outskirts of Melbourne offers one example. When a 400-hectare paddock was bound by kangaroo-proof fencing in 1987, enclosing thirty or so eastern grey roos, their numbers grew to 200 in 1991 and more than 1000 five years later. This proved embarrassing for Parks Victoria, as the reserve was a reintroduction site for endangered barred bandicoots. The bandicoot population plummeted from 120 in 1996 to almost zero two years later. ‘To all intents and purposes the bandicoot population became extinct,’ John Seebeck told me. ‘We were unable to find anything more than possible signs of animals. We certainly couldn’t catch any in our monitoring program.’ Eventually a couple of survivors were found and brought back into captivity. ‘Drought and kangaroo grazing was a fatal combination,’ John said. ‘Woodlands had been a fine example of grassy woodland. It ended up as bare ground. Anything that popped its head out of the ground got eaten – low-growing shrubs, the grasses, the forbs.’ Bandicoots were left exposed to predators.

  When I visited Woodlands in 2000 I spoke to an employee who would not give me his name. ‘The kangaroos were just totally out of balance,’ he said, ‘and the bandicoots paid the price.’ What happened next was predictably controversial. Two-thirds of the kangaroos were culled. It happened after a year of consultation with concerned parties. ‘Animal Liberation was the main opposition,’ Mr Anonymous said. ‘They were cutting the fences and coming in and vandalising places and taking off signs.’ The kangaroos are now under control, and the bandicoots have been reintroduced.

  The dramas in Hattah-Kulkyne and Woodlands have been reenacted in many reserves – Coranderrk, Yan Yean, Portland, Tidbinbilla – and even at Canberra’s most exclusive address. In 1993 seventy kangaroos were culled – and buried – in the grounds of Government House. In ever-growing numbers they were devouring ornamental shrubs, defacing ceremonial lawns and intimidating gardens staff. Multiplying kangaroos cop the blame for many crimes. I’ve heard them accused of destroying endangered plants, eroding soil, eliminating the understorey, preventing regeneration, degrading habitat for birds, promoting rabbits and exotic weeds, and encouraging invasive native plants and birds. They also attack crops and plantation seedlings, hit cars, damage fences, and compete with stock for grass and water. A serious car strike costs an average $3000 to repair, and each year panel-beaters around Canberra earn $200000 from the national icon. Kangaroos also attack people. Biologist Rick Van Veen told me how a childhood friend was ‘disembowelled’ at a sanctuary. The kangaroo raked open his friend’s belly with its hindclaws, exposing his internal organs. The child needed hospital treatment. Attacks like this occur where kangaroos are fed, the animals hugging their victims and tearing with their legs.

  It amazes me how much harm even the smaller macropods can do. On Queensland’s exclusive Hamilton Island agile wallabies and chital deer caused mayhem after winning their freedom from property developer Keith Williams’ private zoo. Four wallabies bred up to almost 5000; deer numbers reached 3000. They took out so much undergrowth that the coral reefs fringing the island were silted up by eroding soil, a remarkable state of affairs. Most of the deer have been shot out but the wallabies are still eroding the steep slopes. It’s another example of landscape change wrought by animals other than humans. Each year a thousand or so wallabies are shot just to control the problem. This island also has trouble with hand-fed cockatoos and currawongs.

  Quokkas are famous in Western Australia as the chubby little chaps who bound around on Rottnest Island, a tourist spot near Perth. The small island carries maybe 10000 quokkas – there are no predators here to control their numbers – but isn’t well suited for them. It’s barren, with mineral-deficient soils and searing dry summers. Most quokkas suffer salmonella infection in summer, and some die from malnutrition and thirst. Some of them survive on succulent plants and others gather around a few meagre soaks. On the mainland quokkas (a rare species) use wetter habitats, but most quokkas on Rottnest today don’t need nature. They graze the golf greens and lawns and beg snacks or scavenge at rubbish tips. The first wild quokka I saw was halfway up a flight of stairs outside a café.

  The quokkas are bad for the island because they browse back shrubs and trees. Most of Rottnest was cleared in the past. Now bushfires sweep through and quokkas destroy any seedling trees. The Rottnest Island pine (Callitris preissii preissii), wattles and tea-trees remain scarce. I looked at one fenced enclosure by a road some months after a fire had been through. Inside, grasses thrived along with baby pines, sedges, and the only kangaroo apple I saw on the island. Outside, where the quokkas could do their work, the ground was bare or carried rank weeds. Quokkas keep Rottnest degraded. Trees would bring in more shelter for birds and offer the quokkas themselves a better diet.

  Quokkas are also a people problem. They enter rooms and bite those who feed and pet them. A Medical Journal of Australia article, ‘Quokka bites’, reported seventy-two nips in eight months, the victims ranging from toddlers to grandparents. The conclusion was comforting: ‘quokka bites heal without infection’. But quokkas sometimes pass on diarrhoea when they excrete salmonella in their dung. They pose a conundrum. Rottnest has a contrived population of quokkas that is important to tourism and conservation, but which is degrading an island that doesn’t suit them well.

  Another macropod running amok is the black-striped wallaby. In New South Wales they are rare, but in central Queensland they multiply like rabbits in the dry rainforest remnants abutting paddocks. Like so many animals found along the forest–pasture interface, they do much better here than in natural settings. The wallabies harry rare black-breasted button-quail by browsing back their cover and disturbing their peace. I’ve seen remnants where the ground looks like a chook pen – all scratched-up sand and dung. A Queensland Forestry report declared that ‘pastoral development and the resulting increase in the population of [black-striped wallabies] has been an important factor leading to the extinction of populations of [button-quail] in remnant patches of scrub’. I mentioned button-quail earlier as the rare bird that likes lantana. A weed is its saviour, a wallaby its curse. Dingoes help control black-stripes, and the wise graz
iers are those who let the wild dogs roam.

  Earlier on I mentioned translocated tammar wallabies and their disastrous impact on Greenly Island, South Australia. As one last example I will mention the Bennett’s wallabies (red-necked wallabies) in Tasmania’s Freycinet National Park that are eating out two rare plants (Stenanthemum pimeleoides and Pseudanthus ovalifolius). ‘The plants are just chewed right down to the ground,’ said Jamie Kirkpatrick, who says that Aborigines kept down wallaby numbers in the past.

  Given all the heartache macropods bring today, we may wonder about the naturalists who feared for their fate. How could Darwin, Gould and Bennett have been so wrong? They evidently saw too much ruthless slaughter of marsupials going on around them. They assumed that extinction would issue from the muzzle of a gun, but in fact its advance would prove stealthier. Australia has lost many mammals to extinction – more than any other land – but only one was defeated by the gun. South Australia’s toolache wallaby succumbed because its distribution was tiny. Adelaide’s conservationists had its demise in mind when they feared for kangaroos in the 1880s. They were right to fear extinctions, but wrong about cause and effect. The real victims of ‘progress’ proved to be the Outback wallabies, along with bandicoots and rodents, brought down by rabbits, foxes, clearing, wildfire, and eat-all herds of cows and sheep.

  Overall, kangaroos benefited from settlement. They multiplied when they could, reclaiming lands lost earlier to hunting. Marsupials have a great capacity to breed up in partially cleared lands. In the nineteenth century, pasture protection boards in New South Wales paid out bounties on vast numbers of bothersome macropods. In 1884, 260780 kangaroo scalps were submitted in the Tamworth district alone. That amounts to 700 scalps a day – in one district. It was around this time that Arthur Robin in Adelaide feared for their future.