Tropical Topics An interpretive newsletter for the tourism industry

Birds of the savannas No. 73 May 2002

Seed-eaters in strife Notes from the ThetropicalsavannasofnorthernAustraliaarehometoa large number of seed-eating – 55 of ’s 90 Editor seed-eatingspeciesarefoundthere.Theyincludeparrots, quails,pigeonsandaparticularlylargerepresentationof Birds living in the sometimes harsh finches – 14 of Australia’s 18 finch species inhabit the savannas. conditions of the savanna lands have had to adapt accordingly. However, studies have shown that many of landholders are Nonetheless, there is a great these birds are in trouble, having beginning to adopt diversity, particularly among seed- disappeared from a number of areas. Seed- new burning regimes. Star finch eating birds, a surprisingly large eating birds are in more trouble than any For graziers, this also number of which are endemic (see other group in the savannas and has the advantage of halting the box, this page). This suggests a savanna seed-eaters are in more trouble loss of grasslands, which are being great age for the savanna than those elsewhere in Australia. invaded by woodland in many ecosystem which is, in fact, Intensive studies of selected species (see places. For the birds, it could mean thought to be about 15 million pages2&7fordetails) have indicated a future. years old – plenty of time for birds some common problems. to have evolved specialised niches. No fewer than 13 species, plus The early wet season is a particularly 10additionalsubspecies,ofseed- This issue of Tropical Topics stressful time for seed-eaters. Most grass eatingbirdsareendemictothe cannot, of course, look at all birds seeds germinate with the early rain, making savannas,meaningthattheylive of the savanna lands but instead it difficult for the birds to find food. Many nowhereelseintheworld. draws together some common juveniles die at this time of year if they threads – problems facing the have not developed strategies for finding Chestnut-backed button-quail seed-eaters and the fruit-eaters – new food sources and learned to quickly Buff-breasted button-quail as well as taking a look at some of identify ripe seed. Partridge pigeon (two the more obvious and charismatic subspecies) species found in the area. A common theme in seed-eater declines White-quilled rock-pigeon (two seems to be changed fire regimes. In the subspecies) I would like to thank Fiona Fraser, past, according to historical records, Chestnut-quilled rock-pigeon Northern Territory University, indigenous people lit fires at almost any Northern rosella Keith Fisher, Greg Czechura, time when it wasn’t raining. Areas burnt at Golden-shouldered parrot Queensland Museum and Steve any one time tended to be relatively limited, Hooded parrot Garnett, QPWS for their help with resulting in a complex mosaic of small burnt Long-tailedfinch this issue. and unburnt patches. The steady removal Masked finch (two subspecies) of fuel meant that fires over extensive areas Yellow-rumpedmannikin Please note were fairly rare. This pattern suited the Pictorellamannikin seed-eaters well, leaving pockets of seed at Gouldianfinch thatyouarewelcometophotocopy Sub-species: Tropical Topics. However, if the different stages of maturity to sustain them throughout the year. textisreproducedseparatelyitmust Littlecorella not be altered and must Fire regimes have changed with the advent Sulphur-crested cockatoo acknowledge the Environmental Australian ringneck Protection Agency as the source. of pastoralism, though patterns vary among landholders. The concentration of Double-barred finch Illustrations must not be reused Black-throatedfinch separately without permission. fire during the dry season means that areas burned are often extensive. This limits the Crimsonfinch Please contact the editor (details Star finch on the back page) if in doubt. amount of food available to the birds. As studies of the birds’ requirements Red-browedfinch illuminate the need for patchy burning, Chestnut-breasted mannikin

1 The fate of finches and pigeons Severalspeciesofseed-eatingbirdshavebeenstudiedindetailinordertopinpointthereasonsfortheirdeclines. Sub-species of star finches and crimson finches The bright colours of Gouldian which were once widespread in Cape York Peninsula finches have led to extensive trapping are now confined to two small populations on the east of these lovely birds for the caged- and west coasts of the peninsula. Studies have shown industry. These finches were once that changes in vegetation on Cape York may be the widespread in woodlands across cause. Both birds depend northern Australia, flocks of on very dense grass. Star thousands providing a spectacular finches nest in it and crimson sight as recently as 50 years ago. They finches rely on it have now disappeared from nearly half for shelter from The crimson their previous range and numbers are Star finch predators while finch continuing to decline. Populations in feeding.Trampling subspecies Queensland have been particularly by cattle, and fires, (Neochmia phaeton badly affected. however, have reduced the availability of evangelinae) found this type of vegetation in drier areas. In in Cape York and Grazing and changes in fire regimes places other than Cape York, where the New Guinea has a seem to be affecting seed availability. finches still thrive, they seem to have white belly (above In the dry season, the finches are able benefitedfromagriculture,particularly right) instead of the to find seeds on the ground in recently Interpretive Birding Bulletin sugar cane, which provides a similarly black belly seen on crimson finches burned areas and in the wet season sheltered . elsewhere in Australia. Differences they like to feed in areas which were in the subspecies of star finch burned in the previous dry season, More profound changes in the (N. ruficauda clarescens) are more targeting perennial grasses. However, vegetation, brought about by cattle subtle. Curiously the bills of both if the areas burnt are too large, they grazing and altered fire regimes are also these endangered subspecies are have problems finding food. Gouldian affecting the birds. Coastal grasslands in smaller than those of their cousins* finches seem to be persisting best in Cape York are being steadily taken over elsewhere. This means they cannot rocky areas, such as the Kimberley, by woodland, dominated by melaleucas handle larger seeds efficiently – where pockets of grassland remain and eucalypts (see p7 for more details). husking them is too time-consuming ungrazed. Diseases have also been In addition, the types of grasses are also – so the range of food available to implicated but are not considered a changing, with species favoured by the themismorelimited. major cause of declines. finches being replaced by those which Crimson finch illustration courtesy are more resilient to grazing but which do *Sub-species elsewhere in Australia not provide the finches with food. On the (N. phaeton phaeton and N.ruficauda Twenty Gouldian finches were other hand, introduced grasses in subclarescens) although also recently released into the wild at the agricultural areas, where the finches are declining in numbers, are thriving in Mareeba Tropical Savanna and not in trouble, may help to feed them. some parts of the Northern Territory Wetland Reserve in north and Western Australia. Queensland. They are part of an Until recently, mystery surrounded the experimentalbreed-and-release whereabouts of star finches in the wet season, after they disappeared from dry program which aims to re-establish season feeding grounds around Princess Charlotte Bay. Then, in late 1999, flocks populations in an area where they were discovered feeding in unburnt grasslands on saltpans near the sea. Star have been absent for 25 years. The finches on the western side of Cape York, however, have a different strategy. birds quickly paired up and have They move into casuarina woodlands where they sit up on the branches picking been nesting. seeds from the cones. Partridge pigeons Partridge pigeons feed on the seeds of more than 60 plant within this limited area – they like to feed in recently burnt species. They are found at the top of the Northern Territory, areas but nest among denser grasses. Their diet also varies. where birds have bright red skin around the eyes, and the Speargrass is an important staple during the dry season. Its Kimberley where a distinct sub-species has bright yellow growth is encouraged by dry season fires. However, like all skin around the eyes. Although able to fly, these birds opt seed-eaters, the birds face a food shortage during the early to walk. Outside the breeding season they gather in groups wet season and, at this time, rely heavily on perennial of 30 or more, cooing softly as they trot together between grasses, such as cockatoo grass, which set seed when the waterholes and feeding grounds. If the grass is too dense, seeds of annual grasses are germinating and sprouting. The they will choose to travel along tracks. When disturbed the amount of seed produced and timing of seed set of these birds initially freeze, only at the last minute bursting up in grasses can be affected by previous dry season burning. flight with swift, noisy wingbeats in a manner reminiscent of These grasses are also less common in areas grazed by partridges. cattle.

These birds are sharing the problems of other seed-eating Tracking of individual pigeons has shown that they birds in the savannas, having suffered a decline in the last respond to food shortage by extending their feeding ranges century and become extinct in many parts of their previous considerably – from an average 8ha to 31ha – in the early range. Their ground-nesting habits have probably left them wet season. However, these birds vulnerable to introduced predators but research indicates do not, by nature, travel great that grazing and changed fire regimes have also had a distances. Extensive dry season negative effect on these birds. fires therefore leave them with limited food for the wet season and reduced Compared with many other tropical seed-eaters, partridge nesting opportunities. Patchy , on pigeons have a small home range and seem to do best where the other hand, with small areas burned at there is variation in the physical structure of the vegetation different times, appear to be ideal.

2 The plight of the parrots Golden-shoulderedparrotswereoncefoundthroughoutCapeYorkPeninsulabuthavebeendeclininginnumbers for at least 80 years and now occur only in two small areas near Musgrave, in the centre of the peninsula, and to thewestofChillagoe.Changedfireregimesareconsideredthemainculpritforanumberofreasons. There is no shortage of food – grass seed – for the parrots, if the area is not overgrazed. Indeed, for much of the dry season they only need to feed for a few hours a day, eating the fallen seed of fire grass, a common annual. They prefer burnt areas where the lack of cover allows them to find seed on the ground easily. The rest of the time they perch, safe from predators, in the trees.

As the fire grass seed germinates with the first rains of the wet season, sprouting grass obscures seeds still lying on the ground. However, if this new growth is burned, ungerminated seeds which remain become visible to the parrots. Fires at this time seem to be vital for the parrots’ survival, allowing them access to seed whichwillkeep them going until the perennial cockatoo Woodswallows stand guard grass produces seeds about six weeks At first glance, it seems unlikely that seed-eating parrots and finches would later. To complicate matters, cockatoo have anything in common with insect-capturing woodswallows. However, grass which is burned after the first researchers have noticed that golden-shouldered parrots and hooded parrots, storms produces up to 10 times more (similar parrots found in southern and eastern Arnhem Land, Northern seed, later in the season, than the Territory) are often to be found feeding on the ground below black-faced unburnt cockatoo grass. Evidently, a woodswallows during the woodswallow nesting season from the late dry to complex mosaic of small areas burned at early wet seasons. Finches too join in – Gouldians, long-tailed and masked different times is most likely to provide finches alongside the hooded parrots in the Northern Territory with blackfaced a sustained source of food for the birds. and masked finches joining the golden-shouldered parrots on Cape York Early wet season burns are particularly Peninsula. Even doves, trillers, sittellas, willie wagtails, leaden flycatchers and important, but if extensive dry season treecreepers have been observed joining the party. fires have already used up the fuel, they may not be possible. It seems that the woodswallows act as sentinels. When a predator such as a butcherbird or kookaburra comes anywhere near their nests, these feisty birds Another aspect is the trend for mob and chase them. This serves as a warning to birds which have their heads grasslands to be invaded by woodland, down, intent on finding seeds on the ground. It allows them to spend more particularly broad-leaved ti-trees time on feeding and less on looking around for danger. Given that (Melaleuca viridiflora) where fires are butcherbirds prey not only on eggs and nestlings but also on adult, breeding infrequent. These trees have a tendency parrots, the woodswallows offer a very valuable alarm service. Whether they to sucker from the base. Frequent fires are repaid for this is not clear. Possibly the seed-eaters disturb a useful number will keep the suckers below grass level of insects as they forage. Once the but once the trees have had a long woodswallows have finished nesting, however, enough fire-free period to grow over a the other birds lose their alarm system, metre in height, only very hot fires will unfortunately at a time when food takes longer to kill them. The presence of these trees find and entails a longer period spent, vulnerable, affect the parrots in two main ways. on the ground. Dense growth cuts out light, thereby reducing grass growth and food Curiously, one group of golden-shouldered parrots resources. They also provide nesting formed an association with grey-crowned babblers, and perching sites for butcherbirds relying on their alarm calls. which are major predators of both Black-backed butcherbirds (above), along with pied butcherbirds, young and mature birds. are major predators of golden-shouldered parrots.

Flyingtree-planters In October 1996, a pied Northern Territory amount to just 0.2 percent of the land imperial-pigeonwas area. captured in a small patch of rainforest in the Nevertheless, these little areas are vital for a suite of fruit- Northern Territory where it eating birds such as pied imperial-pigeons, rose-crowned had landed to feed on fruit. fruit-doves, figbirds, yellow orioles, common koels and This particular pigeon was then great bowerbirds as well as flying foxes. But, just as the tracked for 78 days. In that time it need the forest patches, so the forest patches need travelled65.5km,movingfromonerainforest the animals. They are essential dispersers for plant seeds, patch to another. At each of the numerous sites it visited, with an average patch receiving an estimated 190 seeds a researchers estimated it deposited between 10 and 20 day from their avian visitors. Researchers predict that the seeds in its droppings, many of them having been loss of too many patches would lead to a food shortage – transported from the previous patch of forest. and the consequent loss of these dispersers. The loss of dispersers would, in turn, lead to a gradual decline in Pied imperial-pigeons (also known as Torres Strait biodiversity and, eventually, the loss of remaining patches. pigeons) migrate from New Guinea to northern Australia each summer to breed, and rely on a steady supply of fruit This would be likely to have consequences elsewhere also. from rainforest trees to sustain them. In the Wet Tropics, When rainforest fruit is scarce, the fruit-eaters move into rainforest occupies a fairly continuous strip, but in the surrounding habitats and probably play a dispersal role savanna regions it occurs in patches where local here too. Each patch of forest may seem insignificant, but conditions provide sufficient moisture. Averaging just together they play a vital role in maintaining the network of 3.6ha in size, a total of about 15 000 of these patches in the interdependence which keeps the ecosystem functioning.

3 Savanna characters Birds are a prominent feature of the savanna lands. Some are secretive but some are significant characters.

Wedge-tailed eagles are impressive birds. leave their par- The largest eagles in Australia, and among ents’ territories the largest in the world, they have wing- and go off travel- spans of up to 2.5m. Often, all that can be ling – a banding seenisasmallshape,highinthesky,gliding study in Western on the thermals with its keen eyes searching Australia indicated the ground for food. that they move an average of 228km Thewedge-tailedeagleoncecarriedabounty from the on its head. Between 1927 and 1968, 150 000 nest. One bounties were paid in Western Australia. Ten adventurous thousand were paid in Queensland in a single youngster jour- year.Thecircumstantialevidencewasnotgood neyed748kminjust fortheeagles.Oftenseenfeedingonnewly-dead 11monthswhileanother,in livestock,theywereassumedtobeamajorpreda- Queensland, has been found 868km from its parental home. tor. However, wedgies prefer fresh carrion, if it is available, to hunting and the livestock they have been observed eating was Youngbirdsarebrownwithgolden-brownfeathersonthenape usually dead when they got there – or if killed by the birds, and upper back. Most gradually darken with age, eventually would probably have already been weak or orphaned. becoming almost entirely black when mature, at about five to seven years of age. Some, however, retain their juvenile col- Roadkillsareagreatbonusforthesebirdsalthough,beingslow ours.Wedge-tailedeaglescanliveforover40years.Apartfrom totakeoff,theysometimesbecomethenextvictim,leftfordead itslargesize,itslonglegswithfeathered‘trousers’andpalebill in the verge next to their erstwhile dinner. A wide variety of are distinctive features. In the air, its long diamond-shaped tail animals are also hunted, from lizards to ground-foraging birds is distinctive. asbigasemus,andmammals–themaindietaryitem–including wallabies, kangaroos, possums and in- troducedanimals.Rabbitsareidealprey Red goshawk: our most threatened bird of prey making up to 90 percent of their diet in some areas, although the decline in The red goshawk is Australia’s rarest and most Themainthreatfacingthesebirdsishabitatloss their numbers, due to the release of the threatened bird of prey. and fragmentation, particularly around water- calicivirus, means that the birds have Favouring riverine forests as well as tropical courses.Otherthreatsincludefires,litlateinthe had to turn to other sources of food. and subtropical woodlands and open forests, dry season, which destroy nesting trees and active nests of both the goshawks and their These eagles construct appropriately itoccursacrossthetopofAustralia.Ontheeast coast,itoccursasfarsouthasNewSouthWales prey species, as well as shooting and illegal large nests, weighing up to 400kg, usu- but has now virtually disappeared from this theft of eggs for collections. allyinstrongtrees.Maintainingaterri- state. These birds are swift hunters using their If you see any red goshawks in Queensland, tory, and probably the same mate, for strong feet and claws (the largest, proportion- or just over the Northern Territory border, life, the birds build several nests, using ally,ofanyAustralianraptor)totakeliveprey— Greg Czechura, Queensland Museum would them on a rotational basis. Usually two mainly medium to large birds up to the size of be keen to hear about it. eggs are laid and if food is available Australian brush-turkeys and red-tailed black both will survive. Otherwise, the older Contact Tel: (07) 3840 7642 or Email: cockatoos. Each pair needs a large territory— [email protected]. He is also happy to chickmaykillthesmallerone.Atabout up to 200 square km. answer any queries about raptors. the age of eight months the young birds

Australian bustards are Bustards are generally seen on foot but states of Australia where flocks of up to very similar to those in Af- can fly. If disturbed, they will at first 1000 could once be encountered. This rica, Arabia, India and New freeze, then walk or run away, finally has been blamed on a combination of Guinea.Theyarelargebirds, taking off with a heavy strong flight. At intensive agriculture, the invasion of over a metre in height with a breeding times the male puts on an im- pastoral land by woody weeds, preda- 2.3m wingspan, and can be pressive display. He inflates his throat tion of nests by foxes, pesticides and seenstridingaroundgrasslands sac so that his long neck feathers spread hunting – they were killed by the thou- and grassy woodland. Bustards out in a fan, droops his wings and, with sand from about 1860 until protected in arenomadic,movingaccording tail splayed over his back, produces a 1935. The presence of cattle, sheep and to food sources. They eat grass, series of roars. The female rewards his humans also leads the birds to desert fruit, seeds and large insects as well as efforts by taking full responsibility for their nests. In the north, they have de- mice and reptiles, and are able to survive incubation of the eggs, on the ground. for long periods without drinking. In clined in some places, possibly due to north-west Australia they are very fond There has been a massive decline in woody weed invasion, but in other areas ofmoonflowers. numbers of bustards in the southern seem to have benefited from clearing.

4 Emusinthewildareadramaticsight. She chooses her male and courts him, chasing away other Saidtoreach70km/hatasprintand females who come near. The female is presumably looking for able to cruise at about 45km/h, a mate with stamina. Like cassowaries, male emus do all the theyarenomadictravellers,mov- incubation and raising of the chicks. His mate simply provides ingaccordingtoweatherandfood thedarkgreeneggs–upto20ofthem.Weighing700-900geach, supplies. They have been ob- this is no inconsiderable contribution on her part. A male emu served moving towards clouds and becomes obsessed with eggs – or paddy melons, oil filters or seem to be able to detect rain from stubbies, if he has no eggs to sit on. great distances. Records show that Once he has a reasonable clutch (about seven eggs) the male they can travel over 900km in nine can be quite aggressive to his mate, or any other female, if they monthsandonejourneywasclocked try to add more eggs. He then squats, incubating the eggs non- at 442km in just 80 days. stop for 56 days without leaving to feed or drink. Stretching his Avoidingthickforestandsettledareas,emusarefoundthrough- neck along the ground, he does his best to imitate a rock or pile out the rest of the Australian mainland, adapting to various of vegetatation and goes into a state of semi-torpor. By the end environments and feeding on whatever food they can find – of his ordeal he may have lost up to 25 % of his body weight flowers, seeds, shoots, fruits, stems and insects, including but he then has to care for youngsters, herding them with him grasshoppers when they appear in plagues. They even eat their for up to 18 months. Losses are high, with an average of two own faeces to pick up nutrients which didn’t get absorbed first chicks surviving to adulthood. time round. However, when the breeding season approaches Although numbers of emus are high, they appear to have emus go off their food. As the days begin to shorten, after the declinedinsomeareas,particularlyinlandandtothenorth.The wintersolsticeon21-22December,theskinonthebirds’necks reason for this is unclear. Emus are hardy and can survive becomesabrighterblue.Itisthefemalewhocallstheshots.She drought, but they may be affected by pollution, intensive develops a chest – a pouch and bunch of fluffy feathers – and farming, hunting by farmers protecting their crops, and the struts about with the pouch inflated (see illustration above). effect of changed fire regimes on food resources. On the plus Emu illustration courtesyInterpretive Lynda BirdingThis Strahan/ Bulletin acts as a resonating chamber amplifying her booming call side, farming has benefited emus by providing artificial so it can be heard 2km away. Males grunt in reply. watering holes.

Red-tailed black cockatoos gather in massive flocks sometimes Apostlebirds, so-called because they give several thousand strong – a spectacular sight when these large the impression of appearing in groups of 12 parrots take to the air. The black males have startling bright red (though there may be anywhere between bands in the tail which splays out in flight. The females, and the eightand16inthemob)areanoisyfeatureof young for the first four years, have yellow speckles and bars on their inland Queensland and the NT. They have dark plumage and orange in the tail. There are several sub-species in severalothernames,notably CWA(Country Australia, with different feeding habits. Those in south-western Victo- Womens Association) birds because of the ria are considered threatened but those across northern Australia are noise they make and also lousy jack, for their plentiful. Like many savanna birds, the cockatoos migrate according to tendency to alert animals to the stealthy food supplies. They are more commonly seen in the dry season, approach of traditional hunters. The groups disappearingfrommanyareasduringtheWet.Theyeatavarietyofthings are family clans that work together to build including eucalypt, acacia and banksia seeds, nuts, fruits and insects as well the mud nest and care for the young. The as flowers and nectar. They also feed in recently burnt areas during the dry close-knitfamilyfeeds,drinks,roosts,preens season. Unfortunately the large flocks of cockatoos are not such a welcome and plays together. The birds spend a lot of sight for farmers when they descend on peanut crops. The birds have learned time on the ground and fly weakly. In trees to pull the plants from the ground to get to the nuts underneath. Permits are they prefer to hop from branch to branch on issued to shoot ‘scout’ birds, in order to deter the entire flock and elaborate their strong legs rather than use their wings. scaring methods have been used – but the birds simply move on to another field. As an experiment, a ‘sacrificial crop’ of 40 acres of peanuts was planted at Black kites, known as fire hawks in places, LakelandDownsonCapeYorkPeninsulain1999.Thebirdswereallowedtoeat are attracted by the smoke from bush fires. these but chased from other fields. Largenumberscanbeseencirclingonthermals above burning grasslands, keeping a sharp Kookaburras of two species have overlapping territories in the savannas of lookoutforanimalsfleeinginpanic.Reptiles, north Queensland – the laughing kookaburra and the blue-winged kookaburra. rodents and insects are taken. So useful are The latter is a tropical species with more blue on the wings and tail (male) and fires to black kites, there are unconfirmed a raucous, screaming call in place of the cackling laughter. It is found across reports of them dropping burning sticks to the northern savanna. Where the two species coincide, they exclude each other extend the fire. from their family territories, just as members of the same species would. (Differentspeciesofbirdsoftendisregardeachother.) Itisthoughtthatthetwo The more solitary brown falcon also takes kookaburras were separated for long enough in the past to evolve different advantage of bush fires, pouncing on its forms,butthattheirnestingandfeedinghabitsremainedthesame–thusmaking victimsfromaperchwhereithasbeenwaiting them competitors in the same environment. quietly. It rarely chases prey on the wing.

5 Questions & Answers Facts and stats Numbers of emus are estimated at Q Howdangerousarecrocodiles? well away from the water’s edge. 100000-200000inWesternAustraliaand A Everything is relative. You are • Don’t camp within 50m of water. 525000intherestofAustralia,principally over 6000 times more likely to die in a • Don’t sit on branches overhanging New South Wales and Queensland. road accident than be killed by a a croc creek. Crocs can jump! crocodile.Between1991and2000, • Be cautious when fishing; don’t In 1976 about 100 000 emus – 19,064 people died in road accidents stand in the water. approximately half the Western in Australia. During the same period, • Don’t share food scraps or fish guts Australianpopulation–accumulatedon only one person was killed by a with crocs: they may come back for the northern side of barrier fences crocodile in Queensland, two in the more! protecting the wheat paddocks in the Northern Territory and none in • Don’t assume because someone state'ssouth-west.Mostdiedasaresult. Western Australia. Statistics show else was safe that you will be also: that more people die from road crocodiles are aware of areas In the wild, colouration of Gouldian accidents, drowning, scuba diving regularly used by animals seeking finches varies; in about 70-80 percent of accidents, bee stings, lightning water. Remember you are an animal birds the feathers of the face and crown strikes, shark attacks and box too! areblack,inabout20-30percentofbirds jellyfish stings than from croc • Be careful in boats. Crocs can they are red and in a few, ochre-yellow. attacks. overturn canoes or grab a foot dangling over the edge. Finchescandrinkwiththeirheadsdown. However, it is likely that croc attack • Adults should supervise children Theysuckupwaterandthereforedon’t statistics would be higher if people when near water in croc country. havetotipuptheirheadstoswallow. were not careful. These animals do • Be moderate with alcohol intake in Crimson finches eat large numbers of pose a very real danger and the key croc territory. As with road spiders during the wet season, giving to avoiding becoming a victim is to accidents, most croc attack victims them a protein boost at breeding time. exercise caution and commonsense. have become careless while They have been observed collecting intoxicated. them from the eaves of buildings and Estuarine crocodiles occupy evenenteringbuildingsinsearchofthem. estuarine and freshwater rivers, swamps and billabongs in a coastal Flock bronzewing pigeons once strip around northern Australia occurred in flocks many thousands between Broome in Western QIhavereadthatleechesare strong but a combination of grazing, Australia and Rockhampton in closelyrelatedtoearthworms.Like rabbitsanddroughtledtoalossoffood Queensland. Their range can extend anearthworm,canaleechsurvive suppliesinmanyareas.Theystilloccur quite some distance inland, well into theremovalofsomeofitsbody? in reduced numbers – hundreds – the freshwater reaches of river A No, leeches can heal from wounds, particularlyonMitchellgrass. systems. They also travel along the but they will not regenerate missing coast and can be encountered on parts and will die if the wound is too The red goshawk has been given its own beaches, islands and cays of the bad. This is due to the specialisation genus (Erythrotriorchis rather than GreatBarrierReef. of the leech body. Unlike Accipiter). It may be better categorised earthworms and other oligochaetes, as a hawk-eagle. The key to avoiding a negative leeches always have a fixed number interaction with a crocodile is to be of body segments and have a The squatter pigeon is very similar in ‘croc-wise in croc country’: reduced coelomic system. (The manywaystothepartridgepigeonbutis • Obey crocodile warning signs. Just coelom is the body space or cavity found in the eastern side of Australia, because you don’t see any crocs, between the intestinal canal and while the partridge pigeon occupies doesn’t mean they aren’t there. bodywall.) areasintheNorthernTerritoryandthe • Don’t go swimming, paddling Kimberley.Therearetwoforms.Those or wading in areas where there Acknowledgements to Dr Fredric inthenorthhaveredskinaroundtheeye are likely to be crocs and keep Govedich, whose website on leeches while in the south the skin is pale blue. is at: www-personal.monash.edu.au/ However,somebirdshavebeenrecorded ~fgodevic/leech/index.htm with skin which was half red and half blue,sharplydemarcated. Emus have a wide diet. One shot in 1972 contained in its stomach, in addition to grass and other vegetation, 1 carpenter’s Tourist talk steel-pointedplumb-bob,2plasticelectric ENGLISH GERMAN JAPANESE wallplugs,1wash-tubplug,1springand 3 solid rubber door stops. Emus in finch Fink finch captivity have been known to eat paper, pigeon Taube hato bottle-tops, keys, coins, broaches, cementpowderandbrokenglass–which parrot Papagei oumu emerged with smooth edges. eagle Adler washi emu Emu emu The word ‘bustard’ has links back to Pliny who, in 77AD, called these big grass Gras kusa birdsavistarda,meaning‘slowbirds’. seed Samen tane Intimethisbecamemodifiedtobustard. togerminate keimen hatsugasuru The word ‘emu’ has Portuguese origins burnt verbrannt yaketa inthewordema,meaning‘heron’.Itwas cattle Rindvieh ushi originally used for any large bird.

6 Out and about

A number of cycads (Cycas species) are to The charismatic be found in savanna caterpillars of the four woodlands. They are Happybirthday o’clockmoth(Dysphania often burnt during the Tropical Topics fenestrata) can be seen throughout dry season but Tropical Topics is now 10 the winter months eating the leaves of afterwards produce a years old. It was started in 1992 in their host plant, corky bark (Carallia fresh crown of light response to requests from tour brachiata). Bright yellow, and green fronds. Burning also operators who were attending sometimes green, with black spots, seems to encourage reproduction. workshops in interpretation and who they have a peculiar habit of standing wanted access to a continuing source erect for much of the time. These ancient plants have been of information. Funded by the Wet around for about 230 million years, Tropics Management Authority and before flowers evolved, and theGreatBarrierReefMarinePark produce cones instead of flowers. Authority, the newsletters alternated Plants are either male or female and between blue (marine) and green pollen is blown from the male cone (rainforest) themed issues for many to the female one, although it can years. More recently the Cooperative also be carried by insects, Research Centre (CRC) Reef has notably weevils. The temperature provided funding and since December of mature cones may increase by up to 2000 CRC Savanna has funded four 17 deg. above the local air temperature, ‘orange’ issues dealing with dry The adult is a day-flying moth. usually in the afternoon. The tropics (savanna) themes. Queensland specimens have a yellow breakdown of stored starch body and dark purple wings with and lipids creates the transparent ‘windows’ and yellow heat and this may serve spots. However, this varies across to attract pollinating Australia. In those found in the insects and/or help Northern Territory and north-western the male cone to Australia the purple tends to be duller shed pollen. and the yellow parts of the wing either Rock figs (Ficus orange, or absent. Male cone platypoda) produce reddish purple Femalecone The host plant, corky bark, is Cycas media ‘fruits’ during the interesting in that it is the only member dry season. This of the Rhizophora family which is not a Do you have any photographs of bushy tree, growing to about 8m in mangrove. It is found in monsoon mantarays?MarkSimmonswouldbe height, sprawls over rocks and is forests, vine thickets and in rocky interested to see them. Mark is common in dry rainforest and vine outcrops in open woodland. studying mantas at Lady Elliot Island thickets as well as coastal cliffs across and recently had a major article, with northern Australia. It produces large his photographs, published in the numbers of aerial roots. March/April issue of Australian Geographic magazine. He has tagged You will never see flowers on a fig tree a number of mantas and is currently – unless you cut open the figs. This concentrating on photo identification raises the question of how they are work. As a result, he is keen to see any pollinated. In fact, each fig tree photographs of these magnificent depends on a particular species of tiny animals. They would be used only for wasp (Agaonidae) to do the work. The research, not publication, and process starts with a female wasp acknowledgement would be given flying into a small hole at the top of when the project is finally written up. the fig. Inside the rock fig she finds Thesandpaperfig male,femaleandgallflowers.Before (Ficus opposita) is also widespread Belly shots of the animals are she dies she lays her eggs on the across the top of Australia where it particularly helpful. It doesn’t matter special gall flowers. When the eggs is found as a common understorey when the photos were taken but it hatch, the males mate with the females tree in woodland and open forest. It would be helpful if details of the and die. The females fly around inside has tough, very rough leaves (above) location and time of year could be the fig, carrying pollen from male to which have earned it its common included. Mark would also be femaleflowersbefore name. Most of these fall off during the interested to hear of areas where escaping through a hole dry season if water is scarce. This fig mantas are regularly seen. You could to start the process has separate male and female trees either scan your photos and e-mail again in another fig. The which means that the species of wasp them to Mark at actual fruits are tiny which services it must [email protected] seed-likeballswhichform carry pollen post them to 26 Bultarra inside after the flowers between figs. Crescent, have been fertilised. Figs are Kirwan, QLD4817 popular with birds and flying Gall flowers and he will scan and foxes which eat them but pass, return them or spit out, the tiny fruits immediately. undamaged.

7 Bookshelf Reader’s Digest Complete Book of Issue 15 July-Sept 2000 Australia AustralianBirds Rank grass and sugarcane provide DominiqueBlache Reader’sDigest(1993) succourtonorth’sendangeredfinches Australian Geographic No 58 April- FieldGuidetotheBirdsofAustralia Nature Australia June 2000 Simpson & Day Vol 25 No 3 Summer 1995-96 Superbird(emu) Viking(1996) Redgoshawk Ken Eastwood Stephen Debus Cape York Peninsula – a natural Vol 25 No 5 Winter 1996 Wingspan December 1994 history Golden-shoulderedParrot Golden-shoulderedParrots Dawn W. Frith and Clifford B. Frith Stephen Garnett and Gabriel Crowley Stephen Garnett and Gabriel Crowley ReedBooks(1995) Vol 26 No 9 Winter 2000 KFCwithakick(emu) GEO Vol 22 No2 ARTICLES Steve van Dyck Where eagle scientists dare (wedge- Savanna Links – CRC Savanna Vol 26 No 10 Spring 2000 tailed) Newsletter Boldeagle(wedge-tailed) Monica van Wensveen Issue 3 November 1996 PaulaWinkel ProjecttosavetheGouldianFinch The ecology of the partridge pigeon Issue 6 May-June 1998 Interpretive Birding Bulletin and habitat impacts due to fire and Paradisefaltersforseed-eatingbirds Vol2 No 6 April/May 1999 grazing. DonFranklin Behavioural Profile of the Crimson Fiona Fraser &Rainforestpatchesprovidethelink Finch AvailableontheCRCSavannawebsite Issue 12 Nov-Dec 1999 Michael Todd at: http://savanna.ntu.edu.au/ Fire,grazingandpartridgepigeons Vol 4 No 6 May/June 2001 education/students/current/fiona.html Fiona Fraser Emus: made in Australia, made for

This newsletter is produced by the Environmental Protection Agency with funding from the Cooperative Research Centre for the Sustainable Development of Tropical Savannas, the Cooperative Research Centre for the Great Barrier Reef World Heritage Area and the Wet Tropics Management Authority. Forfurtherinformationcontact... Opinions expressed in Tropical StellaMartin Tropical Savannas CRC Topics are not necessarily those of The Editor Northern Territory University the Environmental Protection Agency DARWIN NT0909 Tropical Topics Ph:(08)89466834 While all efforts have been made to Environmental Protection Agency verify facts, the Environmental POBox2066 CRCReefResearchCentre Protection Agency takes no (10 - 12 McLeod St) POBox772, responsibility for the accuracy of CAIRNS QLD 4870 TOWNSVILLEQLD4810 information supplied in Tropical Ph:(07)47298400 Topics. Ph:(07)40466674 Wet Tropics Management Authority Fax:(07)40466604 © The State of Queensland. POBox2050 Environmental Protection Agency e-mail:[email protected] CAIRNS QLD4870 2002 Ph:(07)40520555

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