WHERE DOALL THE BUSH

BIRDS GO?

Supplement to Wingspan, vol. 9, no. 4, December 1999

WHERE DOALL THE BUSH

BIRDS GO?

In 1989 the RAOU embarked on one of the most ambitious bird

counting projects undertaken in Australia – the Australian Bird

Count. Now the analysis of the enormous volume of data is

beginning to reveal the seasonal movements of our bush birds –

including some surprises.

by Michael F. Clarke, Peter Griffioen and Richard H. Loyn

A u s t r a l i a n B i r d C o u n t

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ii

EVEN A CASUAL OBSERVER KNOWS that the abundance of different birdspecies changes over time and space. What is less obvious is how changes at individualsites fit in with a continental picture of bird movements. By the early 1980s it wasbecoming increasingly clear that species and ecosystems could not be properlymanaged without an understanding of these movements.

Thus it was that in the mid-1980s the RAOU’sResearch Committee decided to embark on anambitious Australia-wide project to gather birdcount data in a consistent and scientific manner.At that time there were already several monitoringschemes under way elsewhere in the world, and theCommittee commissioned a review to determine the

best method to introduce in Australia.1,2 Fourmethods were selected for field testing,3 whichshowed that active methods (transects or areasearches) detected more individual birds and speciesin 20 minutes than stationary methods. A methodknown as active timed area-search4 was found to bethe most popular, and it was also the best-buffered

The Australian Bird Countrelied on the participation

of a dedicated band ofvolunteers throughout the

country. Photo by Jane Miller

Inset: The ABC is helping toclarify the seasonal

distribution of species thatmigrate southward from

the tropics in summer, such as the Fairy Martin.

Photo by Graeme Chapman

A u s t r a l i a n B i r d C o u n t

against variations in counts due to time of day andweather. This, then, was the method selected forthe project.

Responsibility for co-ordinating the project wasgiven to Dr Stephen Ambrose, initially from Sydneyand then from the new Melbourne headquarters ofBirds Australia, where he was appointed as Researchand Conservation Manager. Funding for initial workwas obtained from the Federal Government throughthe Australian Nature Conservation Agency (nowEnvironment Australia), and BP Australiagenerously offered a major sponsorship amountingto $250,000 over five years. With funding secured,the field project began in 1989, and the AustralianBird Count – the ABC – was born.

THE COUNTBetween January 1989 and August 1995, 952observers carried out 78,938 standard surveys at1681 different locations throughout Australia(Figure 1). Others took part intermittently, orhelped with initial testing; altogether, over 2000sites were surveyed by 1020 people. Observers wereasked to select groups of three sites each of about3 hectares, close to each other and in a similar broadhabitat type. Birds were counted regularly on thosesites by 20-minute area-search at least twice a year(summer and winter), but monthly if possible.Forms were used to record the basic details of thelocation and habitat at each site. Simpler forms wereused for submitting count details. Birds observedoff-site were recorded, but not included in the maindata base.

Survey locations were predictably biasedtowards areas close to human population centres.As a result, the eastern half of Australia and thesouth-west of Western Australia received the mostintensive coverage. But observers, like some of thebirds they admire, are somewhat migratory.Northern and inland parts of the continent weresurveyed more often during the cooler, drier monthsof the year than during the summer wet season.Surveys in these remote locations by intrepidobservers during the wet season thus becameparticularly valuable.

Many observers took up the challenge ofsurveying their sites on a monthly basis, or evenmore frequently. Some even provided series of long-term counts from before the ABC. Table 1 shows theobservers who contributed the most number ofsurveys to the count.

PUTTING THE DATA TO WORKWith any large data set it is never easy to interpretdata and present it in an easily digestible form.Modern computer technology has helpedimmensely, but special skills are needed to make thebest use of these new tools. The project benefited

enormously by the fortuitous return to Australia ofPeter Griffioen, from a computer programmingcareer in California’s Silicon Valley.

Peter wanted to use his skills to build a newcareer in conservation, and was quickly introducedto the project and Mike Clarke of La TrobeUniversity as an academic supervisor. Together theyhave cleaned up the data base and developed somepowerful visual tools for viewing it, including

Table 1 Major contributorsto the Australian BirdCount

A u s t r a l i a n B i r d C o u n t iii

Name Town State Numberof

surveys

Mrs K. Hastwell Kinglake VIC 2896S. Telford West Armadale WA 2617The Wardens Norseman WA 1957D. Latham Armidale NSW 1400R. Watson Coffs Harbour NSW 1169F. Ormsby Bondi Junction NSW 1018Mrs S. Rooke Nambour QLD 951D. Lockwood Clayton South VIC 848R. Canning Mt Barker SA 755J. Gleeson Evatt ACT 649N. Cruickshank Tea Gardens NSW 608J. Bannister Alice Springs NT 579C. Whiteoak Coolum Beach QLD 538J. Lacey Red Lion via Talbot VIC 532P. Slack Nelson Bay NSW 532F. Bigg Bribie Island QLD 526C. Hall Paynesville VIC 450Mrs H. Wilson Winnellie NT 432B.L. Schmidt Hawthorndene NSW 407Mrs C. Clarke Annandale NSW 406R. Swaby Malvern QLD 400J. Morrison Albany WA 387Miss M. Pywell Irymple VIC 380S. Lloyd Birralee TAS 371S. Waddell Stanmore NSW 371D. James Forrestdale WA 360

Figure 1

Figure 1 Locations of the

sites at which ABC surveys

were made.

For flocking species such asthe Straw-necked Ibis, a

change in reporting rate isnot a good predictor of a

change in abundance. Photo by Graeme Chapman

Figure 2 The relationshipbetween reporting rate

and mean abundance(birds detected per hectare

in a 20-minute survey),based upon ABC data, for

(a) Red Wattlebird, and(b) Straw-necked Ibis.

animated graphics of seasonal movements. In thisarticle we are unfortunately confined to stationarygraphics, but some animated versions can be viewedvia links on the Birds Australia website:www.birdsaustralia.com.au.

Reporting rate vs abundanceTwo of the major strengths of the ABC data are theintensive repeated surveying effort observers put in atfixed sites over several years, and the collection ofnumerical information. This makes it possible to seehow well changes in the ‘reporting rate’ of a speciesin a region reflected changes in abundance of that

species in the region, as recorded by ABC surveyors.Many bird surveys such as the Atlas of AustralianBirds collect data on a presence/absence basis, withno measure of numerical abundance at each site.Measures of ‘reporting rate’ (the proportion ofsurveys in which a species is detected) are sometimestaken as approximate measures of regionalabundance, but how reliable is this? For example, ifRufous Whistlers were recorded in 75 of 100summer surveys within the catchment of theMurrumbidgee River, and in 10 of 100 wintersurveys in the same region, it might be concludedthat there were more Rufous Whistlers in this regionin the summer – but perhaps they were simply morewidespread in summer and more concentrated inwinter. We really need to estimate the relativenumber of individuals present during each period.The ABC surveyors did this, and so created a uniquedata set with which to examine the strength of thisrelationship between reporting rates and a species’regional abundance.

Peter Griffioen’s analyses revealed that, for most species, there was a very strong relationshipbetween the reporting rate and the abundance of the species in the region, as reported by the ABCcontributors. (The average correlation coefficient for 512 species sampled was 0.81 ± 0.17, calculatedusing the method of Nachman.5) The relationshipwas strong for most species examined, such as theRed Wattlebird (Figure 2a). The red lines represent95 per cent confidence intervals. In other words, we can be 95 per cent certain that our estimate ofthis species’ abundance for a particular reportingrate lies between the two red lines. But theconfidence intervals for species that can form largeflocks (such as the Straw-necked Ibis, Figure 2b) are much further apart, so changes in reporting ratewill not be a good predictor of changes in thatspecies’ abundance.

A u s t r a l i a n B i r d C o u n tiv

Figure 2a

Figure 2b

A u s t r a l i a n B i r d C o u n t

Regional changes in abundanceInformation about the timing of movements israrely obtainable from large-scale bird-banding. In a country the size of Australia, the chance of abush bird that has been banded in one locationbeing recaptured (or the band recovered) in anotherlocation is very small, since there are few people and the area needing to be covered is immense. For example, by 1995 about 270,000 Silvereyes had been banded in Australia,6 but only 458 (0.17 per cent) were recovered farther than 5 kmfrom the site of banding. Of those 458, only 32 (0.01 per cent of birds banded) were recovered in a short enough time to reveal the timing of their movement.7

By combining the ABC data base with otherdata bases, it is possible for the first time to discernregional changes in the abundances of species basedupon large-scale changes in regional reporting rates.However, changes in reporting rates must beinterpreted with caution, because they may alsoreflect seasonal changes in the conspicuousness ordetectability of a particular species. For example, aspecies might be present in a region during the non-breeding season, but be hard to detect whennot calling. Even so, for many species, majorchanges in reporting rate can tell us much aboutchanges in abundance over time and space. This isthe case for the Grey Fantail in eastern Australia(Figure 3 a–d). Most of the population appears towinter in northern New South Wales, coastalQueensland and Cape York, but then largelyabandons these regions in summer to breed incoastal New South Wales, Victoria and Tasmania.For the maps shown here, surveys conducted within45 days either side of 8 March, 8 June, 8 Septemberand 8 December have been pooled as ‘autumn’,‘winter’, ‘spring’ and ‘summer’ respectively, withgreater weighting being given to surveys carried outcloser to those central dates.

For some parts of the country it is possible toproduce maps for every fortnight of the year,because of the huge number of surveys available.Such a series of maps can then be arranged inchronological order, and when run through on acomputer in quick succession produce remarkableanimated depictions of the changes in distributionof the species as the year unfolds. Grey Fantails are astriking example, as discussed above. This is the firsttime the depiction of the scale and timing of suchlarge-scale movements has been possible.

Seasonal distributionsThe analysis of the ABC data is now giving us amuch clearer picture of when and where birds aremoving. Bird-watchers often have a good idea ofwhen migrants come and go from their own localarea, and discuss these events in newsletters andelectronic media such as birding-aus. But now forthe first time we can generate maps of suchmovements at the continental scale.

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Thanks to the sterling efforts of thousands ofvolunteers, Birds Australia and affiliatedornithological organisations possess someextraordinarily large data sets. These include thefirst Atlas of Australian Birds, the NSW Atlas, andthe Canberra Ornithologists Group’s data base.With the computerisation of these data bases, theycan now be combined to provide a very powerfulresearch tool. The core of this power lies in thehuge number of surveys it represents – more than 4.5 million records.

Above: In eastern Australia,many Grey Fantails appearto winter in northern NewSouth Wales, coastalQueensland and Cape York,but then largely abandonthese regions in summer tobreed in coastal New SouthWales, Victoria andTasmania.

Left: Banding studies arenot always useful forstudying seasonalmovements. By 1995 about270,000 Silvereyes had beenbanded in Australia, butonly 32 were recovered in ashort enough time to revealthe timing of theirmovement. Photos by GraemeChapman

A u s t r a l i a n B i r d C o u n tvi

Figure 3 Eastern distribution of the Grey

Fantail during ‘autumn’,‘winter’, ‘spring’ and

‘summer’. Units are birdsper hectare that might

be detected in a 20-minute survey.

no data

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0 ≤ 0.25

0.25 ≤ 0.5

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1.0 ≤ 2.0

> 2.0

Figure 3a Figure 3b

Figure 3c Figure 3d

Autumn Winter

SummerSpring

Sometimes the maps confirm what many haveknown for years regarding the timing and locationof movements of some species, such as theDollarbird, Shining Bronze-Cuckoo and RainbowBee-eater (Figures 4–6). But in other cases,unexpected or poorly documented seasonalmovement patterns have been detected. Forexample, some field guides describe Richard’s Pipitas sedentary, but the ABC and Atlas maps suggestthis species spreads in a south-easterly direction insummer, increasing in abundance in Tasmania,Victoria and southern New South Wales (Figure 7).Another example is the annual movement up anddown the north coast of New South Wales andsouthern Queensland of the Scarlet Honeyeaterpopulation (Figure 8). Much of the Golden Whistlerpopulation appears to spread inland in winter, butspends summer in the ranges or closer to the coast ineastern Australia (Figure 9).

These kinds of maps can also be used to identifyregions in which migratory species are present allyear round – a circumstance that spawns an array ofadditional questions. For example, although many

Grey Fantails appear to abandon south-easternAustralia for warmer northern regions in winter(see Figure 3b), many do not. Are these individualsmembers of non-migratory sub-populations of thespecies, or are they a particular age-class of GreyFantails (such as adults) that do not migrate? Thereis evidence that Grey Fantails and other speciesfavour drier, more open habitats in winter than insummer. No doubt, dozens of similarly intriguingpuzzles will emerge as these maps and data areexamined more closely. These questions might wellbe important for the recognition and conservationof sub-populations within larger species complexes.

Seasonal changes from controlled sitesOne of the strengths of ABC data is thatcomparisons can be made between identical sets ofsites surveyed at different times with known effort.This means that we can check whether apparenttrends in maps prepared using Atlas data might bedue partly to seasonal changes in observer behaviour(for example, when bird-watchers visit the interiormore in winter than summer). A summary table has

Above left: The seasonaldistribution maps haveconfirmed what many haveknown for years about thetiming and location ofmovements of somespecies, such as theRainbow Bee-eater.Photo by Graeme Chapman

Above: Some field guidesdescribe Richard’s Pipit assedentary, but the ABC dataand Atlas maps show that itspreads in a south-easterlydirection in summer. Photo by Dave Watts

A u s t r a l i a n B i r d C o u n t vii

A u s t r a l i a n B i r d C o u n tviii

Figure 4 Eastern distribution of the

Dollarbird during ‘autumn’,‘winter’, ‘spring’, ‘summer’.Units are birds per hectarethat might be detected in

a 20-minute survey.

no data

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0 ≤ 0.25

0.25 ≤ 0.5

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1.0 ≤ 2.0

> 2.0

Figure 4a Figure 4b

Figure 4c Figure 4d

Autumn

Spring Summer

Winter

A u s t r a l i a n B i r d C o u n t ix

Figure 5a Figure 5b

Figure 6a Figure 6b

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Figure 5 Eastern distribution of the ShiningBronze-Cuckoo during‘winter’, and ‘summer’.Units in all maps are birds per hectare that might be detected in a 20-minute survey.

Figure 6 Eastern distribution of the RainbowBee-eater during ‘winter’,and ‘summer’. Units in allmaps are birds per hectarethat might be detected in a20-minute survey.

Winter Summer

Winter Summer

Figure 8 Eastern distribution of the

Scarlet Honeyeater during‘winter’, and ‘summer’.

Units in all maps are birds per hectare that

might be detected in a 20-minute survey.

A u s t r a l i a n B i r d C o u n tx

Figure 7 Eastern distribution of the Richard’s

Pipit (shown above left,with a Red-throated Pipit!)

during ‘winter’, and‘summer’. Units in all maps

are birds per hectare thatmight be detected in a

20-minute survey.

Figure 7a Figure 7b

Figure 8a Figure 8b

no data

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0 ≤ 0.25

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Winter Summer

Winter Summer

A u s t r a l i a n B i r d C o u n t

been constructed for selected species showing meanbird abundances in summer and winter, basedexclusively on sets of ABC sites surveyed in all fourseasons (Table 2, see p. XII). The data were sorted byState, with the ACT grouped with New South Wales,Queensland divided into north and south at latitude25°S, and Western Australia divided likewise atlatitude 30°S. Each site was given equal weighting incalculating means, regardless of how often it wassurveyed. These regions were then grouped furtherafter inspection of seasonal data for each species.(Note that ABC data are based on a less compre-hensive set of sites and habitats than Atlas data, withsome obvious biases, e.g. there were few sites ininland Australia, cleared pasture or extensive forests.)

The data provide clear and controlled evidencefor winter declines of many common species insouthern Australia (especially Tasmania) and winterincreases of some of them in northern Australia(Table 2). The limited data from the north suggestthat summer departures of southern migrants weregreater from the Northern Territory and northernWestern Australia than from north Queensland.However, often these species were numerous inwinter in far north Queensland, but the seasonalpattern was obscured by the inclusion of sites furthersouth in this vast region. This may have applied tospecies such as the Fairy Martin, Satin Flycatcher

and Leaden Flycatcher: the last species in particularis known to be a common winter visitor on CapeYork. Winter exoduses from Tasmania were evidentfor the Flame Robin, Grey Fantail, Tree Martin,Welcome Swallow, Striated Pardalote and Silvereye,in contrast to the Golden Whistler and SpottedPardalote which showed no net seasonal changein Tasmania.

In Western Australia, many species were morecommon in summer than in winter in the south, andin some cases the limited data from the northsuggested a winter increase there (e.g. WesternGerygone and Richard’s Pipit, Table 2). Silvereyesshowed no net seasonal change in the south-west(Table 2), though we would expect them to movebetween habitats within the region. Grey Fantailsappeared to be more common in winter than summerin southern Western Australia: sites near Perth mayattract a winter influx from wet forests in the farsouth-west, where fewer surveys were conducted.

The State-based tabulation (Table 2) obscuressome known habitat shifts, often involving a winterexodus from wet forests into drier habitats. For somespecies this involved westward extension of range inwinter, clearly evident from Atlas maps (e.g. GoldenWhistler and Spotted Pardalote).

Some honeyeaters and pardalotes were morecommon in winter than in summer at most sites

xi

Figure 9a Figure 9b

Figure 9 Eastern distribution of the GoldenWhistler during ‘winter’,and ‘summer’. Units in allmaps are birds per hectarethat might be detected in a20-minute survey.

Winter Summer

no data

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0 ≤ 0.1

0.1 ≤ 0.2

0.2 ≤ 0.4

0.4 ≤ 0.8

> 0.8

Species Region Summer Winter

Azure Kingfisher NT, NQld, SQld 18 16NSW, Vic 5 1

Black-faced Cuckoo-shrike NT + NWA 38 63NQld + SQld 154 119SWA 59 61elsewhere 99 44

Dusky Woodswallow NQld + SQld 1 5NSW + Vic + SA 43 19Tas 288 2

Fairy Martin NT + NWA 0 9NQld 249 207elsewhere 46 11

Golden Whistler NQld 34 15SQld 98 133NSW + Vic + SA 66 57Tas 74 99

Grey Fantail NQld 18 411NT + NWA 1 40SQld 68 411NSW + SA 168 159Vic + Tas 339 215

Leaden Flycatcher NT 32 87NQld 57 38elsewhere 16 2

Magpie-lark NT 61 181NQld 268 516SQld 179 225elsewhere 128 119

Rainbow Bee-eater NT 153 169NQld 485 228SQld 101 68NSW + Vic + SA 37 6

Richard’s Pipit NT + NWA 1 21N,SQld + NSW + SA + Vic 7 6Tas 11 0

Rose Robin SQld 3 17NSW 1 9Vic 2 0

Rose-crowned Fruit-Dove NT + NQld + SQld + NSW 14 4Rufous Fantail NQld + NT + NWA 7 50

SQld + NSW 23 3Vic 7 0

Rufous Whistler NQld + NT 44 80SQld 64 67NSW + Vic + SA 117 7

Sacred Kingfisher NT + NWA 12 47NQld 20 14SQld + NSW + SA + Vic 44 3

Scarlet Honeyeater S + NQld 38 160NSW 21 7

Silvereye NWA + NT + N,SQld + NSW + SA 257 538SWA 455 453Vic + Tas 280 198

Spotted Pardalote NT + S,NWA + N,SQld + NSW + Vic 55 111Tas 147 141

Striated Pardalote NWA + NT + N,SQld + NSW 36 98SA + Vic 162 150Tas 306 30

Tree Martin NWA + NT + NQld 58 194SQld + NSW + Vic + SA + SWA 144 117Tas 41 0

Western Gerygone NWA 0 44SWA 192 138elsewhere 2 1

White-throated Gerygone NQld 19 46SQld 20 16NSW + Vic 19 1

Willie Wagtail NWA + NT + NQld 77 177SQld + SA 112 115NSW + Vic 173 82

Yellow-faced Honeyeater NQld 19 14SQld + NSW 101 389Vic + SA 132 151

Notes: 1 summer = 8 Dec ± 45 days; winter = 8 June ± 45 days2 Table is based on data from 54 sites counted in all four seasons in northern Queensland, 88 in

southern Queensland, 301 in NSW–ACT, 133 in Victoria, 39 in Tasmania, 72 in South Australia, 94 in southern WA, 9 in northern WA and 23 in NT.

3 Each site was given equal weighting in calculating means, regardless of how often it was surveyed.

A u s t r a l i a n B i r d C o u n tx11

surveyed, as they tend to be summer visitors toextensive forests (with relatively few ABC sites) andwinter visitors to more accessible habitats. The well-known north–south migrations of Yellow-facedHoneyeaters were clearly evident from New SouthWales and Queensland data but further analysis isneeded to assess habitat shifts within Victoria andSouth Australia (Table 2).

Additional statistical analyses based on habitatsand bioregions are being carried out and thereremains great scope for other researchers to use thedata to answer questions of interest to them or toland managers.

SOME MYSTERIESThe ABC data set has not only solved somemysteries: it has created some too. Maps generatedfrom combined ABC and Atlas data suggest thatDusky Woodswallows were more common insummer than in winter through most of their easternrange. They are clearly summer migrants in thesouth, but where do they go to in winter? The ABCdata point to a winter increase in Queensland (Table 2), though only low numbers were recordedthere on ABC sites. Field guides give their view ofwinter range (e.g. Pizzey & Knight 19978), but do wereally know? Inland areas of Queensland clearlydeserve further attention in the future.

Azure Kingfishers were recorded more often insummer than in winter in southern mainlandAustralia during the Atlas; but was this merelybecause observers spent more time around riversduring summer? The limited ABC data also suggest a summer increase on the sites surveyed in bothseasons (Table 2).

Rose-crowned Fruit-Doves were observed moreoften in summer than winter throughout their tropicalor subtropical range, yet ABC–Atlas maps show aremarkable consistency in distribution across seasons(Table 2). Perhaps the ABC data reflect conspicu-ousness while breeding, or do birds move into moreaccessible habitats in the humid summer season?

Some unexpected trends emerged for speciesgenerally regarded as sedentary (Table 2). Forexample, there was an apparent summer increase ofMistletoebirds in the Northern Territory and awinter increase of Magpie-larks in the NorthernTerritory and north Queensland (as also reportedin the first Atlas). Willie Wagtails were morecommon in summer than winter at sites surveyed inVictoria and NSW–ACT, and vice versa in northQueensland. Long-distance movement has neverbeen suspected in this species, so the results mayreflect local habitat shifts occurring independentlyin each region – or do they? Further investigation isin order.

Table 2 Mean abundance of selected species byregion in summer and winter. Figures are birdsobserved per hectare per 20–minute survey (x 1000).

A u s t r a l i a n B i r d C o u n t xiii

Long-term changesThe period covered by the ABC was too short todetect long-term nation-wide trends. Year-to-yearchanges were examined for 12 selected species, usingdata from sites counted in each of the five years from1990 to 1994. Three woodland birds thought to bedeclining – Scarlet Robins, Hooded Robins andSpeckled Warblers – were included in this group.9,10

Mean densities of two woodland birds (ScarletRobins and Hooded Robins) appeared to declinegradually from maximum levels in 1990. However,the density of Speckled Warblers, another ground-foraging bird of the open woodlands, appeared toincrease over the same period. These opposing resultsimply a need for very long-term data sets to detect allbut the most dramatic changes in bird populationson a national scale.

CONSERVATION IMPLICATIONSKnowing when and where birds move around thecountry is fundamental to the sound management oftheir habitat. Some areas, such as river courses orlarge remnants of native vegetation, may be identifiedas being significant migration routes or stopoverpoints in the movement patterns of several species.For example, when examining the seasonal maps forthe Red-tailed Black-Cockatoo in inland New SouthWales, seasonal movements by cockatoos are clearly

Far left: DuskyWoodswallows are clearlysummer migrants in thesouth, but where do theygo to in winter? Inlandareas of Queensland couldbe the answer. Photo by Rob Drummond

Above: The Magpie-lark isusually thought of as asedentary species, but theABC data indicate a winterincrease of Magpie-larks inthe Northern Territory andnorth Queensland. Photo by Graeme Chapman

Left: Very long-term dataare needed to detect all butthe most dramatic changesin bird populations on anational scale, especially forwoodland birds that appearto be declining, such as theHooded Robin.Photo by Graeme Chapman

A u s t r a l i a n B i r d C o u n txiv

occurring along the Darling River (Figure 10). Thisquantitative evidence of the importance of suchcritical features of the landscape should strengthenthe case for their preservation and carefulmanagement, and highlight the importance of theselife-giving arteries in an arid landscape.

Birds Australia and its affiliates have been co-ordinating surveys such as the ABC for more than20 years: a period during which the Australianlandscape has undergone some major changes. As datafrom the current New Atlas project accumulate,comparisons will be made with the older data sets.Many important conservation-related questions willbe able to be addressed. For example, we will be ableto identify those species that have suffered significantreductions in their range or abundance in the 20 yearssince the first Atlas (1977–81). We will also be able todocument the spread of introduced species such asCommon Myna or Common Starling in the east, orLaughing Kookaburra in the west, or the degree towhich native ‘pest’ species such as Noisy Miners andPied Currawongs are increasing in abundance orrange. The ABC data will be an important steppingstone between the two field Atlases.

The first Atlas led to many major conservationinitiatives for Australian birds. We anticipate that ourability to identify conservation priorities will be fargreater in the next few years as the New Atlas projecttakes another snapshot of the state of our birds,which we can then compare with the pictureproduced as a result of the efforts of past Atlassersand ABCers (or ‘Cabbies’ – Counters of AustralianBirds). We hope that this direct link between the datacollected by volunteers and conservation initiativeswill stimulate even more people to get out theresurveying our amazing birdlife, and analysing results.

Right: In inland New SouthWales, Red-tailed Black-

Cockatoos appear to movealong the Darling River. The

quantitative evidenceprovided by the ABC datahighlights the importanceof such life-giving arteries

in an arid landscape.

Below: The ABC data willhelp us to document the

spread of introducedspecies, such as the

Laughing Kookaburra inthe west.

Photos by Dave Watts

Further information

For further analysis using Atlas or ABC data, see theBirds Australia website: www.birdsaustralia.com.auor contact research staff at Birds Australia, or theauthors:

Dr Mike Clarke, Dept. of Zoology, La Trobe University, Bundoora, Vic 3083; email: m.clarke@zoo.latrobe.edu.au

Peter Griffioen: email: pgriffioen@pobox.com

Richard Loyn, Arthur Rylah Institute (Dept. of Natural Resources and Environment),123 Brown St, Heidelberg, Vic. 3084;email: richard.loyn@nre.vic.gov.au

ABC results have been used for a number of researchand conservation purposes (e.g. Griffioen 1996). Amore complete set of results has been placed on theAustralian Broadcasting Corporation (the other ABC)website for Birds Australia at www.abc.net.au/birds.

A u s t r a l i a n B i r d C o u n t xv

A C K N O W L E D G E M E N T S

Main thanks to the 1000+ volunteers who contributed their time and expertise to collecting field data for the ABC and associatedprojects (e.g. testing methods). Special thanks are also due to BP Australia and Environment Australia for funding the field project,which was initiated by Richard Loyn and supported strongly at various stages by Margaret Cameron, Dr Stephen Davies, Dr PhillipMoors, Barry Baker, Brian Snape, Dr David Baker-Gabb, Dr Mike Newman, and others. The project was co-ordinated by DrStephen Ambrose throughout its field phase, ably assisted by volunteers in Sydney and Melbourne. This work was overseen by asteering committee of Dr Phillip Moors and then Dr David Baker-Gabb (Chairs), Barry Baker, Marilyn Hewish, Richard Loyn andBruce Male. Dr Khalid ab-Dabagh and Heather Gibbs assisted with data collation. Peter Griffioen and Dr Mike Clarke made a piv-otal contribution to checking datasets and bringing them into a usable form.

Current (1999) efforts to produce this report and website were overseen by a committee consisting of Richard Loyn (Chair),Dr Mike Clarke, Peter Griffioen, Marilyn Hewish and Barry Baker.

Special thanks go to Frank Knight and HarperCollinsPublishers for permission to reproduce Frank’s superb illustrations fromThe Field Guide to the Birds of Australia by Graham Pizzey and Frank Knight (Angus & Robertson, 1997).

Edited by David Meagher and Merrilyn Julian; layout and production by P.A.G.E. Pty Ltd; printing by Buscombe Vicprint Ltd.

no data

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Figure 10a Figure 10b

Figure 10 Distribution of the Red-tailed Black-Cockatoo in NewSouth Wales and southernQueensland during ‘winter’and ‘summer’. Units in allmaps are birds per hectarethat might be detected in a20-minute survey.

Winter Summer

A u s t r a l i a n B i r d C o u n t

CONSERVATION THROUGH KNOWLEDGE

ACN 004 076 475415 Riversdale Road, Hawthorn East, Vic. 3123Tel: (03) 9882 2622; Fax: (03) 9882 2677Email: mail@birdsaustralia.com.auBirds Australia Home Page: http://www.birdsaustralia.com.au

Founded in 1901, Birds Australia (Royal AustralasianOrnithologists Union) is Australia’s oldest nationalconservation organisation, dedicated to the study andconservation of native birds and their habitat. New membersare welcome.

The Australian Bird Count was generously supported by theAustralian Nature Conservation Agency (now EnvironmentAustralia) and BP Australia.

Funding for the publication of this supplement was generouslyprovided by the Wettenhall Foundation.

Wingspan is the quarterly membership magazine of Birds Australia. Additional copies of this supplement

are available from the National Office.

Printed on recycled paper.

R E F E R E N C E S1 Smith, P. 1986, Monitoring the Populations and

Movements of Australian Birds: A Project Proposal,RAOU Report 25, RAOU, Moonee Ponds.

2 Smith, P. 1987, Monitoring the Populations andMovements of Australian Birds: Workshop Report,RAOU Report 28, RAOU, Moonee Ponds.

3 Hewish M. & Loyn R. H. 1989, Popularityand Effectiveness of Four Survey Methods forMonitoring Populations of Australian Land Birds,RAOU Report 55, RAOU, Moonee Ponds.

4 Loyn R. H. 1986, ‘The 20 minute search – asimple method for counting forest birds’,Corella, vol. 10, pp. 58–60.

5 Nachman, G. 1981, ‘A mathematical model ofthe functional relationship between densityand the spatial distribution of a population’,Journal of Animal Ecology, vol. 50, pp. 453–60.

6 Baker G. B., Dettman E. B., Scotney B. T.,Hardy L. J. & Drynan D. A. D. 1997, Reporton the Australian Bird and Bat Banding Scheme,1995–96, Environment Australia, Canberra

7 Griffioen P. 1996, Investigation of birdmovements using the Australian Bird Count:A pilot study based on the Silvereye, Zosteropslateralis, Grad. Dip. Thesis, Dept. of Zoology,La Trobe University, Bundoora.

8 Pizzey, G. & Knight, F. 1997, The Field Guideto the Birds of Australia, Angus & Robertson,Sydney.

9 Robinson, D. 1993, ‘Vale Toolern Vale: theloss of our woodland birds’, Wingspan, vol. 9,pp. 1–3, 20–21.

10 Robinson, D. & Traill, B. J. 1996, ConservingWoodland Birds in the Wheat and Sheep Belts ofSouthern Australia, RAOU ConservationStatement No. 10, Supplement to Wingspan,vol. 6, no. 2.

Cover photo: Birdwatching in the Mallee Graeme ChapmanInset left: Striated Pardalote Rob DrummondInset right: Scarlet Robin Dave Watts

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