Monday, September 7, 2009

List of my Australian Fauna writings from "Brucie Bilby"

1 PLATYPUS

Common Name : Platypus, “Flat-foot”

Scientific Name : ornithorhyncus paradoxus, “Bird-Nosed Paradox”

Order: Monotremata*

Family: Ornithorhynchidae

Subspecies: None

Status: Not presently threatened, but lush habitat seriously eroded by settlement.

Natural range : Coastal NSW & Queensland, Eastern Victoria, Tasmania.

Hazards: Dogs and foxes; whilst juvenile, probably cats; pollution or usurpation of watercourses by grazing animals.

Comments : Platypus is deservedly popular choice for world’s foremost living oddity. It is one of only two monotremes - mammals which lay eggs - the other being the Echidna, also an Australian native, see p.( ) Both monotremes are true mammals in that they produce milk to feed their young, but neither has nipples: the milk simply exudes from the mother’s underbelly, and Platykits and Echidna pups lap it off her fur.

With webbed feet and a broad bill to shame any duck’s, rich waterproof fur and a flattened tail not unlike a beaver’s, Platypus looks like a creature from A Midsummer Night’s Dream. Still more astonishing is the fact that the adult male possesses on his hind legs “spurs”, capable of injecting into unwary handlers a neurotoxin, with potentially serious effects. ( Platypus is the only poisonous mammal in the world.)

Yet unquestionably the creature’s most fascinating attribute is to be found in its bill,

a sensory organ capable of detecting electrical impulses in the nervous systems of the freshwater crustacea and waterliving insect larvae which form the bulk of its diet. This sense, the like of which is found nowhere else in Nature, enables Platypus to locate prey at some little distance, even though they swim with eyes closed whilst underwater. Serrate ridges on the contact surfaces inside the pliable bill serve instead of teeth; larger prey such as freshwater crayfish are brought to the surface to break into swallowable lumps. Although notoriously shy, they learn to accept quiet observers, and their vigorous style of foraging and swimming makes them a sight worth waiting for.

[ Note that rather than the ugly plural “Platypuses”, or the pedantic “Platypi”,

we prefer the simple plural Platypus, as is the case with one or many sheep.]

References :

Tasmania’s Native Mammals, Phil Andrews, Tasmanian Museum and Art Gallery, Hobart, 1981

Key Guide to Australian Mammals, Leonard Cronin, Reed Books, Sydney 1991

Australian Mammals in Colour, Irene & Michael Morcombe, Reed Books, Sydney, 1979

The Puffin Book of Australian Mammals, Helen Hunt, Puffin, Melbourne, 1990

The Australian Museum Complete Book of Australian Native Mammals,

R. Strahan (Ed.), Angus & Robertson, Sydney, 1983

Sanctuaries where you may go to see Platypus:

NSW : (Probably several)

NT : ( ? None - ? )

Qld : (Probably several)

SA : 1. Warrawong Sanctuary, Adelaide Hills, Ph. …….. Website www. …etc….

2. Flinders Chase Sanctuary, Kangaroo Island, Ph. ….. ……..www……….

Tas : (Probably several)

Vic : Healesville Sanctuary ………

WA : ( ? None - ? ) (etc …)

Elsewhere in the World : ??????????

*( Hyperlink would embrace Echidna, explain egg-laying mammals etc, but not in great depth, and anyway in your own words. )

2 Marsupial Mole

Common Name : Marsupial Mole

Scientific Name : notoryctes typhlops

Order: Polyprotodonta*

Suborder Dasyuromorphia

Subspecies: None

Status: Difficult to assess. Rarely observed. 1 specimen only captured in last decade.

Natural range : Arid areas of Central Australia..

Hazards: Uncertain. Grazing activities have probably degraded its habitat.

Foxes possibly dig out individuals close to the surface

Comments : The Marsupial Mole has been found over a wide area of inland Australia, usually as a result of ploughing activities. So accidental a mode of discovery does not lend itself to in-depth studies of behaviour, and very little is known of many aspects this bizarre little marsupial. About the size of a Chiko Roll, which it quite resembles, it has no external eyes whatsoever, though subcutaneous vestigial lenses are present; ears are reduced to hollows packed with dense fur, and the tail to little more than a stump. Using the two tusk-like toe-nails on each front foot, it burrows vigorously through loose sand, the hole filling in after it passes, so that it seems rather to swim through the sand than to dig. The nose is horny and spatulate, in shape reminiscent of that of a Koala’s, but set at a shallow angle; it is used to push loosened soil above and behind itself as it progresses. Though most of its burrowing is within the top twenty centimeters of soil, shafts may suddenly plunge vertically for as much as two metres

Though the Marsupial Mole spends most of its life below ground, it may emerge occasionally to forage for insect larvae, and sometimes goes to sleep above ground. During this time it must be intensely vulnerable to introduced predators, whereas whilst underground it is relatively safe from them. Unfortunately, foxes can of course dig too, and since much of the Marsupial Moles’s activity is within a few centimetres of the surface, one must wonder as to how many are excavated by the incomparably larger animal.

How rare is this strange little creature ? The most common assessment, which is no more than guesswork based on distribution, is that it is not in the front line of threatened species; yet so rarely are specimens found that any given individual might, for all anyone knows, be the last of its line. Within the last decade or so, only one has been discovered ( that one being alive and well at the time). It is unlike any other marsupial – though it is superficially extremely similar to the Golden Moles of Africa, down to the twinned front digits and reduced eyes, though the African Moles do have tiny external eyes whereas Marsupial Moles have none at all. Those true moles, however, are placental mammals, in no way related to notoryctes; the similarity is an example of convergent speciation, the growing-alike of quite unrelated animals which happen to share similar lifestyles. Baleen Whales and Whale-Sharks in the way they feed on krill, Beaver and Platypus in body shape, Old World Shrews and Australian Antechinus, Koala and Three-Toed Sloth of South America, all are examples of convergence, but no case is more spectacular than that of these little subterraneans.

Research into a creature at once so rare, so specialised and so fascinating as notoryctes typhlops must be tempered with extreme circumspection, yet there is a vital need to know much more about it if we are to ensure its survival. It seems unlikely that it will prove an easy task to establish breeding colonies in sanctuary or in artificial conditions, and without this option it is more than ever critical that known habitat be conserved and “de-predatored”.

Tasmanian Devil

Common Name Tasmanian Devil

Scientific Name: sarcophilus harrisii, “lover of cadavers”

Second to the Thylacine, ( the“Tasmanian Wolf”, now almost certainly extinct ),

this Staffordshire-Terrier-sized native to Tasmania is the next-largest marsupial predator. Although known to take fowls and undefended lambs, it is primarily a carrion-feeder, hence the scientific appellation. It has uniquely powerful jaws, capable of exerting point-pressures beyond those of any other mammal; this impressive equipment enables it to consume the hardest of bones.

Although its eyesight is weak, its physique less than athletic, its appearance unprepossessing, its vocalizations daunting, and its name a continuing public-relations disaster, this very literal bete noire has adapted to cope well with the same European invasion which exterminated its larger relative. It is common throughout the island State, and may sometimes be found foraging in suburban gardens. It is also well-adapted to semicaptivity, and will readily breed in sanctuary conditions; this apparently puts its survival beyond doubt, provided that there is no recurrence of disastrous disease epidemics such as are known to have occurrred at least twice in the last century.

This is an example of a native animal whose fortunes have been influenced both adversely and advantageously by homo sapiens. Before the coming of any humans to Australia, both Thylacines and Devils were widespread on the mainland as well as Tasmania. Successive waves of Aboriginal peoples, bringing the physically-superior Dingo, canis familiaris, were almost certainly responsible for the extermination of both large marsupial predators from mainland Australia, the Devil as recently as 600 years ago. On the island of Tasmania, never reached by dingoes, both species survived until after European settlement. The last known Thylacine died in captivity in 1936, leaving to posterity ghostly jerky images on film. The Devil at some times has seemed destined to share the same sad fate, but in the last half-century attitudinal changes have led to increased interest in our fauna, and in the case of this particular species, Europeans appear to have ensured its survival by re-introducing it to the mainland, in situations where it is able to breed – if only in sanctuaries.

Tasmanian Devils may be seen at . . .

4 Wombats

FamilyVombatidae

There are at least three species of wombat surviving to this day, and at least one sub-species or species, the King Island Wombat, which has become extinct since European settlement. The three survivors find themselves in vastly different circumstances, from the true-to-name Common Wombat, vombatus ursinus, which exists in safe numbers and with several sub-species over a great deal of South-Eastern Australia, through the Southern Hairy-Nosed Wombat lasiorhinus latifrons, common within a limited range on the arid Nullarbor Plain and in pockets elsewhere in South Australia, to the rare Northern Hairy-Nosed Wombat lasiorhinus krefftii, which is found in sparse populations in a few small enclaves of New South Wales and Queensland. The endangered status of the last-mentioned species, as compared with the more comfortable position of the other two, vividly points up the need for well-meaning conservationists to discern clearly between rare and common species; this is the core of the message in Brucie the Bilby.

Wombats have no near relatives, the Koala being the closest. The order to which they all belong, Diprotodonta, includes the extinct giant Diprotodon, a hippopotamus-sized marsupial possibly seen off by early Aboriginal predation, and whose salt-preserved (as distinct from fossilized ) bones have been found in the vast, usually-dry salt-pans of central South Australia. A splendid skeleton has long been a centrepiece at Adelaide Museum. All Diprotodontids are ( and were ) vegetarian, but where the Koala has specialised in a leafy tree-top existence, feeding largely on a few species of Eucalyptus leaves, Wombats have opted for an earthy life, accessing a wide range of vegetable material including roots, from which they extract most of their water needs. All three species are great diggers, creating prominent warren complexes which may be kept in use indefinitely by successive tenants if circumstances remain suitable. Burrows may be fifteen metres in length and are deep enough to provide insulation from the extremes of temperature – from the desert heat of the Nullarbor to snow conditions in the Australian Alps – to which the different populations are subject. In most cases lacking access to water, Wombats conserve their body fluids by staying in their humid burrows during the heat of the day, emerging at night to feed on dew-damp vegetation when conditions allow.

Although as a rule sedentary, they will often roam several kilometres in a night, returning to their digs by dawn. They are often to be seen sitting at the entrance to their burrows during pleasant weather. Though they shamble along with a rolling gait when relaxed, they gallop when alarmed, and are capable of a very creditable 40 km/hr over short distances – much faster than the comparably-sized Tasmanian Devil, whose best effort reportedly does not exceed 13 km/hr.

Wombats may be found at . . .

5 Glider Possums ( Phalangers )

Family Petauridae

There are four species of phalanger: Greater Glider, petauroides volans, Sugar Glider petaurus breviceps, Yellow-Bellied Glider petaurus australis, and the Squirrel Glider, petaurus norfolsensis. The smallest is about the size of a European rat, the largest nearly the size of a rabbit. ( The tiny Feathertail Glider, acrobates pygmaeus, smaller than a mouse, is a possum of a different feather altogether.)

Of the four, the first two are common, the third and fourth rare. All inhabit tall forest, and all except the Greater Glider feed substantially on a combination of plant saps, nectar, pollen, manna, and honeydew, an exudate from bark-dwelling invertebrates. Birds’ eggs, insects and other animal-protein sources are used to supplement this diet. Greater Gliders, by contrast, feed almost exclusively on Eucalypt leaves.

All gliders are true-to-name in that all volplane on the membranous skin along the flanks.When not acting as an aerofoil, this looks like a fur coat five sizes too big.

In glides this membrane is tensioned by extending all four limbs rigidly in a

St. Andrews Cross configuration. Glides are spectacular in the extreme: the possum flings itself off its branch in the general intended direction, and navigates with a combination of weight-shifting and aerodynamic changes to its body shape, while the tail acts as a rudder. In-flight directional changes through as much as 90° are not uncommon. Gliders seem unconcerned by strong winds, taking them in their glide,

so-to-speak. Near the end of each glide the little aeronaut angles steeply upwards, flattening its body such that the air trapped between its belly and the targeted tree-trunk cushions the impact of landing. In the instant prior to touchdown, the head is thrown far back, averting injuries of the tongue-biting kind. Gliders may reach a tree running, much as one may jump a wide puddle without breaking stride. Horizontal distance covered may exceed 100 m. in some species.

Gliders may be watched at . . .

Needs differentiation of places and situations for different species.

6 Yellow-Footed Rock Wallaby

petrogale xanthopus

Xanthopus is one of at least 9 species of Rock-Wallabies whose common names are worth comparing. All family petrogale, they are: Black-Footed, Brush-Tailed, Unadorned, Godman’s, Rothschild’s, Yellow-Footed, Proserpine, and Short-Eared, and the Warabi, which escaped the fate of one of our imaginative European names.

Most have declined in numbers and in distribution since the coming of Europeans, but fortunately, perhaps because they are Rock-Wallabies, and live in some of the most rugged and inaccessible parts of Australia, all seem so far still to survive.

The spectacularly-ornamented wallaby we feature in Brucie the Bilby was once a plentiful species, but may now be found in the wild only in what were once the farthest-flung reaches of its original range. It has not been well-served by the coming of Europeans, who have done much more than merely to trade in large numbers of its decorative pelts in the early part of last century. We have, more importantly, altered its habitat to suit grazing pursuits, and introduced serious competition in the form of husbanded sheep & cattle, and feral goats, donkeys, rabbits & camels; goats and rabbits in particular are destructive of its food plants. The introduction of feral cats and foxes has also made deep inroads into Yellow-Foot’s population and range, adding new predators to a list which already included the Dingo – itself introduced by or with Aboriginal peoples – and the mighty Wedge-Tailed Eagle, the wallaby’s one enemy for which humans are not to blame, and which does have prior hunting rights.

Only partly because this outstandingly beautiful wallaby has been chosen as South Australia’s faunal emblem, interest in the species is high, and some attempt has been made to eliminate the all-consuming goats from its Northern Flinders range, though the rabbit seems proof against all control measures so far ranged against it. To help ensure Yellow-Foot’s survival, a number of breeding populations have been established in semi-captivity and in sanctuary conditions where foxes and cats are excluded. Though this is a sorry second-best to wilderness conditions, it does seem that for the moment the species is at least fairly secure, if much reduced. It is to be hoped that, with increasing environmental awareness, Yellow-Foot’s plight will soon be alleviated by serious pro-active measures at Governmental level.

7 Numbat myrmecobius fasciatus

This engaging little denizen of open sclerophyll woodland provides an object lesson in the urgent need for conservation in Australia. A very early mammal, unique amongst Australian marsupials in that it has specialised in termites as a food source, it has through the aeons evolved a set of teeth which are many in number (52) but tiny in size, and which are not actually used for chewing the soft-bodied prey. Unusually for Australian marsupials, it is diurnal by nature, sleeping at night in hollow logs which are often lined with dry fibrous vegetable matter. Emerging at dawn, it may spend the whole day foraging, exposing tunnels in termite colonies by burrowing, and licking up the residents in large numbers, with rapid flicks of its long. sticky, prehensile, worm-like tongue. Victims are swallowed whole.

No larger than a European Rat, and with no defensive capability whatsoever, Numbats fall easy victim to the introduced predators, cats and foxes. This fact in particular, coupled with destruction of its habitat by agriculture and by frequent bushfires, has led to a disastrous decline in Numbat population and in its range, from what was once a huge swathe of the largely-arid Southern and South-Western Australia, to a remnant area, less than Tasmania in extent, just North-East of Perth. Even here it is far from secure, with cats still not subject to any organized control measures, and with shrinking resources of the fallen timber needed for its food insects to flourish. Some breeding colonies have been established in cat-proof sanctuaries in South Australia,

and it is to be hoped that a sufficient gene-pool of these charming little creatures will be maintained until felinity levels decrease. Not before then can any re-introduction to wilderness hope for success, even where its original range there are plentiful termites.

8 Ghost Bat macroderma gigas

Bats (Chiroptera) are placental mammals, widespread throughout the world except where extreme cold or great distance from water preclude their lifestyle.. They migrated to Australia aeons ago, probably across land bridges which existed where New Guinea and the islands of Indonesia remain. They are the only mammals capable of true flight, and they fly very well indeed, both fast and with an agility probably superior to any bird’s. However, their wings are a very-lightly-furred, silk-stocking-fine webbing of living muscle tissue and skin, spanning the extremely-extended fingers, and are very much less efficient than the wings of birds. Feathers are modified scales - non-living material requiring no blood supply - and therefore lose no heat energy beyond the negligible amount generated by friction. From such a large surface area relative to their tiny bulk, the little insectivorous bats, or “flittermice”, lose a great deal of heat in flying on cold nights.The consequence for them is that they must feed quickly and efficiently in order to stay ahead of their immediate energy needs. Whilst roosting, many allow their metabolic rate to fall extremely, sometimes to a rate of one percent of that during flight, and to temperatures barely above their surroundings. Some cling to walls of caves or abandoned dwellings, beneath treebark or in any hidden shelter which is unlikely to be disturbed; Fruit Bats suspend themselves upside-down from their hooked, parallel claws, neatly wrapping their wings around themselves like raincoats.

Torpid flittermice revive rapidly when externally warmed, and can fly swiftly around in any sizeable room, proving very difficult to recapture, and also how accomplished they are at aerobatics, (no pun intended ! ).

There are many species of bat world-wide, including the dreaded blood-loving Vampire of South America, a species now under threat itself. The tiny Vampire typically lands quietly near a sleeping mammalian host, clambers softly onto its throat or ankles, bites into a surface vein without waking the sleeper, and laps the blood. Victims include most large mammals such as calves, goats, donkeys and, yes, humans. Little damage is done to the host in any given feeding session, but repeated visits by several Vampires may result in serious blood loss. Much more of concern is that the little nightcomer is known to be a vector for rabies in humans. For this reason, rather than its actual appetite, attempts have been made by public-minded citizens in some places to exterminate Vampires. Poison, strychnine in particular, is smeared on the back of captured specimens, which are then released; when they fly home to roost, their companions obligingly lick them clean, so poisoning themselves. This pro-active campaign, along with the destruction of the South American habitat which parallels Australia’s own, has put the little Vampire under extreme threat. A stern word here: Humans exterminate any species to the planet’s loss, and in special cases such as creatures to which we are hosts, to our own peril. The human flea is a case in point. Is it extinct since the introduction of DDT ? W.H.O. failed to find one for . . .

No Australian bat shares the Vampire’s taste for blood. The species featured here, the Ghost Bat, is a False Vampire, Australia’s only carnivorous bat predating creatures other than insects, but it does not extend its attacks beyond small animals it can kill and carry off.

Bats are divided into two main groups: Fruit Bats, Suborder Megachiroptera, and Insectivorous Bats, Microchiroptera. Australia has eight of the world’s 150-odd species of Fruit Bats, which are often called Flying Foxes for their generally foxy, rather handsome faces. In some species adults can weigh in excess of 1 kilogram, though the blossom-feeding species are much smaller than the fruit-eaters, with some only around 12-20 grams. Many of the insectivores are relatively tiny, with individual species in which adults weigh as little 3 grams, about the weight of a teaspoonful of salt, minus the spoon. The Ghost Bat is midway between the two main groups in size, around 150 grams, and is the sole Australian representative of its family, the Megadermatidae; a few other species in the same family exist in Asia and Africa.

Fruit Bats are highly social in their roosting and flying habits, and large numbers flying overhead can often darken the sky and half-deafen listeners on the ground as they set out to sometimes-distant feeding trees. Their jaws and teeth are not strongly developed; they feed exclusively on juices lapped from very ripe fruit. No species in Australia is presently endangered, though one, the Bare-Backed Fruit Bat, is rare in Australia; populations elsewhere are greater.

The Insectivorous Bats, of which there are hundreds of species worldwide, are amongst the most numerous and successful of all mammalian groups. Many have facial features which are bizarre in the extreme, with heavily-convoluted “nose-leaves” which direct soundwaves, huge ears with strange appendages within, and, in most species, tiny eyes – though none is blind, the popular simile notwithstanding. They have extremely highly-developed echolocatory systems, enabling them to avoid obstacles and to locate insects in absolute darkness, an ability not shared by owls. A phased series of short high-pitched squeaks is uttered, the bat pinpointing the prey by successive approximation, presumably building a 3-D image of its surroundings from the echoes. Some insectivorous bats, sometimes called the Whisperers, are just audible to humans: some sound like a piano’s top C, stuck repeatedly at successively shorter intervals ranging from a second down to as little as one two-hundredth of a second. The Screamers, by contrast, produce sounds quite beyond our audible range; just as well too, for in decibel terms, the volume of sound they do make is extreme, comparing with a Lear-Jet at take-off. ( Reportedly: I can’t say I’ve heard it myself ! ) These bats use noise to disrupt the flight of insects: the voice is amplified and directed by the wing membranes, and infra-red film of these bats catching moths seems to indicate that the prey suffers effects akin to audiogenic fits as the bats blast them with sound waves.

The Ghost Bat is our sole representative of its particular family, the Megadermatidae.

Paler than most bats, it is distinctive in appearance, with a prominent nose-leaf, tall ears joined for part of their height down the centre-line, and large eyes, better developed than those of most microchiropterans. It is less dependent on echolocation, using also its excellent vision to find prey, which includes most small birds, insects, reptiles, amphibians and small mammals, including other smaller bats. Hunting with a technique like a small nocturnal falcon, it captures flying prey on the wing, and often in the wing, as one catches a baseball in the webbing of a baseball mitt. Larger prey is taken to a convenient place to devour.

Ghost Bats’ range covers a large part of Northern and Central Australia, but they are sparse and few in number. They are unfortunately very sensitive to human activity, and this has led to a disruption of their social behaviour in many places. Necessary protection measures must include exclusion of humans from brooding sites, and as always, it is vital to discern the rare and threatened species from commonplace, abundant and plague species if we are to maximize the effectiveness of would-be conservation measures..

9 Quolls

Quolls are Dasyurids, distantly related to the Thylacine, the Tasmanian Devil, and more closely to many smaller marsupials including a dozen different Dunnarts, eleven Antechinus, four Planigales, two Phascogales, and two Ningaui, well as several individually-categorised species : Dibbler, Kowari, Mulgara, and Kultarr. The bizarre little Marsupial Mole is thought to be very distantly related too.

All are essentially carnivorous, and the smaller members of the superfamily, many of which closely resemble the unrelated placental Shrews elsewhere in the world, are every bit as voracious as those notorious little creatures. All except the Devil and perhaps the largest Quoll, the Spotted-Tailed, are physically monstered by the introduced cats and foxes; to boot, environmental destruction is in many places total, so that few species are safe. Some are probably extinct, with many rare or threatened.

There are four species of Quoll, largest of surviving Mainland marsupial carnivores.

They are the Spotted-Tailed Quoll, dasyurus maculatus, and the Eastern Quoll dasyurus viverrinus, Western Quoll, d. geoffroi, and Northern Quoll, d. hallucatus, unimaginatively if accurately named, though the Eastern Quoll should possibly now be re-named the Tasmanian Quoll, since it appears to be extinct on the Mainland.

All species are expert hunters. They work by night, moving swiftly over open ground, probing likely rock crevices and hollows in fallen logs. They take all manner of prey within their capabilities, and prefer fresh kills, but will also take carrion. They also include grasses, fruits and berries in their highly-varied diet. Lacking a fully-prehensile tail and opposed thumbs, Quolls are less adapted to an arboreal lifestyle than most Possums, but they are nevertheless competent climbers, avidly raiding accessible birds’ nests and exposing bark-dwelling lizards and insects.

Quolls are not long-lived, about seven or eight years being about the limit. Across all species they become sexually mature at one year of age, and may continue to breed for several years, but more usually do so only whilst quite young. Mating is a protracted affair, lasting many hours at a session, and apparently confirming a pair-bond at least for that breeding season. Males are 25-40% larger than females, and take an active part in defending shared nesting-hollows, and in providing some food for the gravid females.

Female Quolls in some species may produce as many as thirty tiny embryonic babies, each about the size of match heads, but since the females of all species have only either six or eight nipples, to each of which only one embryo can attach itself, only the first ones to secure themselves nipples can survive. This is probably a very fine “coarse filter” to ensure that females do not waste precious bodily resources on weak individual offspring. The babies stay attached to the teats in the forward-opening pouch until suckled, remaining there during weaning until the space there is no longer adequate; then they hang on to their mother’s back, in exactly the same way as do baby American Opossums, which are after all marsupials too. Mortality during the parenting phase is low, and successfully-reared Quoll families of at least five are not unusual in good conditions. It is when young Quolls have to begin fending for themselves that they are subject to heavy losses. Without effective cat control, the future of all four Quolls must remain under a cloud.

10 Bilbies and Bandicoots

Many of our Bandicoots are now restricted to the arid lands too dry for human activity, and in some cases to the offshore islands where cats and foxes are not. The (uniquely) Pig-Footed Bandicoot is extinct, and several other species are breathlessly close-to-the-edge. Some, however, such as the Brown Bandicoot of the Eastern Coast, which is common throughout much of its range including the leafier suburbs of Northern Sydney, have proved capable of prospering under the heel of European settlement. Few are well-known beyond the scientific community, and there needs to be a great deal of public education about these less-than-honoured natives.

All the true Bandicoots have stiff bristly coats; Bilbies are distinguished by their soft fur, and also by their habit of constructing well-appointed burrows. Two species have been identified, the Bilby macrotis lagotis, and Lesser Bilby macrotis leucura, but the latter, never plentiful, now appears certainly to be extinct. The species remaining exists in a much-reduced area at the extreme and most-arid limits of a range which once embraced two-thirds of the continent. As is the case with most native mammals, it has been devastated by Europeans’ destruction of its habitat and by the introduction both of competitive species such as rabbits and goats, and the introduced predators, cats and foxes. Fortunately for its potential survival, the Bilby is a most appealing member of our wildlife, and its cause has been taken up in new-age sanctuaries, where staff are having some success in breeding programmes, mainly by providing predator-proof habitat. From almost complete obscurity the Bilby has in the last decade become one of the best-recognised of our native fauna, to the extent that Chocolate Bilbies have even become popular alternatives to Easter Bunnies. This does indicate a hopeful trend in our awareness, and indeed the little Bilby has become an ambassador for and icon of Australian conservation. [ Hence the choice of Brucie.]

Somewhat larger than a rabbit, smaller than a hare, the Bilby has ears to shame both of those introduced placentals: not just for appearance, nor purely for hearing neither, though they certainly play a role in both. Paper-thin and parchment-like, sparsely- furred, and visibly lined with many bright-red blood vessels, the ears’ other function is probably to shed excess heat rapidly. The fur on the rest of the body is extremely soft and fine, from white through beige to slaty blue-grey, but the predominance of the prominent nose and pinnae tends to gives Bilbies a pinkish look. The tail, starkly black-shafted and white-flagged, is very nearly majestic, being held stiffly erect when the animal moves at speed; Bilbies are very nimble, but in fleeing appear to feint and dodge away, rather than to jump as do wallabies, or to run as do rabbits. The whitish hindfeet are surprisingly kangaroo-like, though the hind limbs are neither so specialised nor so disproportionate to the forelimbs as are those of the Macropods generally. On the contrary, the front legs are particularly well-developed, with sharp strong claws which are used vigorously in digging for roots and in dislodging fallen timber in search of invertebrates and lizards. Bilbies excavate comfortable, deep burrows in which they pass the entire daylight hours, venturing out only after dark.

11 Koala

Of all Australian fauna, second-best-known only to the Kangaroo is the Koala.

Yet for all its great popularity, this archetypally “furry cuddly” marsupial is by no means a secure species, being beset by some particularly intractable and unpleasant problems. Apart from the shameful mass slaughter for the pelts of these quintessentially-inoffensive and defenceless animals in times now long past, these include continuing destruction of and encroachment on its habitat, attack by domestic dogs, road trauma, and damage to the front teeth in falls, especially in situations such as Port MacQuarie, where suburban housing has intruded on areas frequented by Koalas. In attempting sometimes-impossible crossings from one tree to another they often fall face-first onto house-roofs, keeping local diprotodontists busy all the year round repairing their dentition..

Of greater concern still are the diseases to which Koalas are prone. Many become blind through a condition akin to opthalmia, and more again are rendered sterile by chlamydia, an ovarian disease known to be affecting a large proportion of females in most populations. It is urgent that these health problems be investigated, and solutions found, if we are to avoid the threat of a possible catastrophe in Koalaland .

Where Koalas live in concentrated numbers, as in the Flinders Chase Sanctuary at the Western end of South Australia’s Kangaroo Island, they put such pressure on their food trees that would-be conservationists must consider the horrifying and paradoxical option of culling, since resettlement is not an option, most potential habitats already having their own resident populations. The alternative to this regrettable action may be that the food-trees die, as has already occurred to some.

Perhaps the biggest single threat is from Eucalyptus Dieback Disease, a phenomenon of huge concern for us all, but of course most worrisome to Koalas, already beseiged by the sea of troubles outlined above.

It seems certain that Koalas and Wombats evolved from common ancestors, but whereas Wombats have evolved to eat a wide variety of plant foods, Koalas have become one of the most highly-specialised of marsupials, perhaps second this time to its very distant relative, the Marsupial Mole. Koalas feed almost exclusively on the leaves of Eucalypt (“Gum”) trees – and only about a dozen species of gum at that.

Of those species, most in turn become toxic to Koalas for at least part of the year, and they must be able to swap species as and when the need arises. It is conjectured that in the wild they may ingest small amounts of some other species of Eucalypt - even perhaps different plants altogether when they are under ideal conditions where they have a wide choice, or perhaps when to the contrary they are in desperate circumstances where there is nothing else – but there is no doubt that gumtree leaves form the vast bulk of the diet, so that within the very limited variety that that diet does afford, it is vital to Koalas’ well-being that they get exactly the right stuff at any given season.

Koalas have evolved a number of unusual adaptations to their arboreal habit. Unlike most mammals, Koalas stay out in all weathers, never seeking shelter, and rarely if ever drinking, at least whilst healthy. They must rely on their thick woolly fur to protect them from the extremes of winter and summer, which can range from below freezing to heat-wave conditions that may see runs of eight or ten consecutive days with maximum temperatures well above that of the human body. To survive in all conditions, Koalas need to derive maximum nutriment from their food, which is low in available protein and high in toxic oily materials, and especially to conserve what moisture they can garner from gum tips. This requires effort more of a cerebral than a physical kind, so Koalas spend a great of time in deep thought in any hammock-like fork in a shady tree during the heat of the day, and even at night will often cease feeding to have a think. The daunting task of digesting Eucalyptus leaves – with their volatile, pungent antiseptic oils in sufficient concentration to sting human eyes – is left to micro-organisms in the caecum, the organ which in humans is reduced to the vestigial if pesky appendix, but which in Koalas is taken to the other extreme, for they have in proportion to their size the largest caecum of any mammal. Digestion takes considerable time, which is why Koalas sleep so much. [ The placental mammal most comparable in life-style, the 3-Toed Sloth of the New World, is even less active, to the extent that in its tropical rainforest habitat its hair becomes host to a luxuriant growth of greenery.]

Koalas have but one joey as a rule, a rule that has been broken just once, and that very recently as at this writing. Milo and Otis are the first-known Koala twins, born in Melbourne towards the end of 1999 and first brought to public notice in January 2000. Media attention world-wide has been focussed on these little charmers, and will no doubt follow them all their days. This fanfare and publicity is of no direct benefit to our wildlife in general, nor even to Koalas in particular, yet on the other hand it is indicative of the real yearning which most people feel to see our wildlife more sensitively conserved. If that well-meaning attitude can be tapped for the physical and financial support which it presages, if serious effort is directed to educating the public to discern and protect the creatures that are rare, rather than wasting resources on those in no danger, perhaps our wildlife may look forward to a future in which they are treasured, rather than regretfully back at our callous, simplistic and ignorant past.

12 Echidna

There are two species of Echidna, only one of which, the Short-Beaked Echidna, is native to Australia. The other is the much larger Long-Beaked Echidna of New Guinea. Collectively they represent one-half of all surviving Monotremes, (egg-laying mammals), the other being the Platypus.

Echinoderm means spiny-skin, and Echidnas are very aptly so named. The spines are modified hairs up to the length of a human finger, and are very hard and sharp, and strong enough to pierce a sandshoe with ease. They are interspersed with bristly hairs which cover most of the body, the hair becoming softer as it gets shorter, so the Echidna in effect wears a luxuriant suit of fur-lined armour. Its protection has proven highly effective in defence against all comers, for Echidna enjoys the most extensive range of any indigenous animal, that being virtually 100% of Australia including Tasmania, Kangaroo Island and most other off-shore islands. Under threat, Echidna curls up underneath, becoming a spiky hemisphere with no vulnerable part exposed. Anyone who has picked chestnuts, or tried to handle living sea-urchins or the most forbidding of cacti, need not stretch his imagination far to get the picture. On diggable ground the defensive Echidna will excavate underneath itself, the spines along its flanks wedged firmly into the soil of the developing hole, making the animal very hard to dislodge without leather gloves and digging tools. In easy ground it simply seems to disappear, betraying nothing of the vigorous efforts it is making below the level of visibility, a little in that sense like the proverbial duck. On impossibly-hard ground or paving, it will simply curl up and wait until the threat passes. For the most part Echidna displays an unworried, unhurried, rather whimsical demeanour, shuffling along without taking much notice of human observers. Nowhere is its population dense, yet it seems to be stable, partly because unlike Numbat it includes the ubiquitous true ants in its diet, as well as the less-plentiful termites which are Numbat’s exclusive food; partly because in its armour it is largely proof against those introduced villains, foxes and cats. A superb digger, Echidna easily breaks into termite mounds, and explores the mazes of galleries with its long sticky tongue. Eggs, larvae and adult insects alike are taken in great numbers, along with large amounts of their detritus, which is probably also essential for Echidna’s digestion and nutrition.

A solitary species except in mating season, Echidna does not form pair-bonds, the female taking the responsibility of caring for the young entirely by herself. For this she is well-equipped, without the expenditure of a great deal of special effort. She lays only one smallish soft-shelled round egg directly into her own pouch, where in a little more than a week it hatches. The pup remains there for the 3 months of the “suckling” phase, though as with Platypus this term does not truly apply; the mother has no nipples, nor does the infant have a sucking mouth, instead simply lapping milk exuded from the mammary glands in the pouch. During the earlier stages of maternity the female spends much of her time in a burrow, but for most of the year, given the lack of need for haven from predators, the shelter of logs or tussocks of grass suffices.

Copyright Bruce Bilney 1999