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Australian Count WHERE DO ALL THE BUSH GO?

In 1989 the RAOU embarked on one of the most ambitious bird counting projects undertaken in – 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

Supplement to Wingspan, vol. 9, no. 4, December 1999 ¢ ii Australian Bird Count

The Australian Bird Count relied on the participation of a dedicated band of volunteers throughout the country. Photo by Jane Miller

Inset: The ABC is helping to clarify the seasonal distribution of that migrate southward from the tropics in summer, such as the Fairy Martin. Photo by Graeme Chapman

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

Thus it was that in the mid-1980s the RAOU’s best method to introduce in Australia.1,2 Four Research Committee decided to embark on an methods were selected for field testing,3 which ambitious Australia-wide project to gather bird showed that active methods (transects or area count data in a consistent and scientific manner. searches) detected more individual birds and species At that time there were already several monitoring in 20 minutes than stationary methods. A method schemes under way elsewhere in the world, and the known as active timed area-search4 was found to be Committee commissioned a review to determine the the most popular, and it was also the best-buffered Australian Bird Count iii

Table 1 Major contributors against variations in counts due to time of day and Name Town State Number weather. This, then, was the method selected for of to the Australian Bird the project. surveys Count Responsibility for co-ordinating the project was Mrs K. Hastwell Kinglake VIC 2896 given to Dr Stephen Ambrose, initially from S. Telford West Armadale WA 2617 and then from the new Melbourne headquarters of The Wardens Norseman WA 1957 Birds Australia, where he was appointed as Research D. Latham Armidale NSW 1400 and Conservation Manager. Funding for initial work R. Watson Coffs Harbour NSW 1169 was obtained from the Federal Government through F. Ormsby Bondi Junction NSW 1018 the Australian Nature Conservation Agency (now Mrs S. Rooke Nambour QLD 951 D. Lockwood Clayton South VIC 848 Environment Australia), and BP Australia R. Canning Mt Barker SA 755 generously offered a major sponsorship amounting J. Gleeson Evatt ACT 649 to $250,000 over five years. With funding secured, N. Cruickshank Tea Gardens NSW 608 the field project began in 1989, and the Australian J. Bannister Alice Springs NT 579 Bird Count – the ABC – was born. C. Whiteoak Coolum Beach QLD 538 J. Lacey Red Lion via Talbot VIC 532 P. Slack Nelson Bay NSW 532 THE COUNT F. Bigg Bribie Island QLD 526 Between January 1989 and August 1995, 952 C. Hall Paynesville VIC 450 observers carried out 78,938 standard surveys at Mrs H. Wilson Winnellie NT 432 1681 different locations throughout Australia B.L. Schmidt Hawthorndene NSW 407 Mrs C. Clarke Annandale NSW 406 (Figure 1). Others took part intermittently, or R. Swaby Malvern QLD 400 helped with initial testing; altogether, over 2000 J. Morrison Albany WA 387 sites were surveyed by 1020 people. Observers were Miss M. Pywell Irymple VIC 380 asked to select groups of three sites each of about S. Lloyd Birralee TAS 371 3 hectares, close to each other and in a similar broad S. Waddell Stanmore NSW 371 habitat type. Birds were counted regularly on those D. James Forrestdale WA 360 sites 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 the location and habitat at each site. Simpler forms were used for submitting count details. Birds observed off-site were recorded, but not included in the main data base. Survey locations were predictably biased towards areas close to human population centres. As a result, the eastern half of Australia and the south-west of received the most intensive coverage. But observers, like some of the birds they admire, are somewhat migratory. Northern and inland parts of the continent were surveyed more often during the cooler, drier months of the year than during the summer wet season. Surveys in these remote locations by intrepid observers during the wet season thus became particularly valuable. Many observers took up the challenge of surveying their sites on a monthly basis, or even more frequently. Some even provided series of long- term counts from before the ABC. Table 1 shows the observers who contributed the most number of Figure 1 surveys to the count. enormously by the fortuitous return to Australia of Peter Griffioen, from a computer programming career in California’s Silicon Valley. Figure 1 Locations of the PUTTING THE DATA TO WORK Peter wanted to use his skills to build a new sites at which ABC surveys With any large data set it is never easy to interpret career in conservation, and was quickly introduced were made. data and present it in an easily digestible form. to the project and Mike Clarke of La Trobe Modern computer technology has helped University as an academic supervisor. Together they immensely, but special skills are needed to make the have cleaned up the data base and developed some best use of these new tools. The project benefited powerful visual tools for viewing it, including iv Australian Bird Count

For flocking species such as animated graphics of seasonal movements. In this species in the region, as recorded by ABC surveyors. the Straw-necked Ibis, a article we are unfortunately confined to stationary Many bird surveys such as the Atlas of Australian change in reporting rate is graphics, but some animated versions can be viewed Birds collect data on a presence/absence basis, with not a good predictor of a change in abundance. via links on the Birds Australia website: no measure of numerical abundance at each site. Photo by Graeme Chapman www.birdsaustralia.com.au. Measures of ‘reporting rate’ (the proportion of surveys in which a species is detected) are sometimes Reporting rate vs abundance taken as approximate measures of regional Two of the major strengths of the ABC data are the abundance, but how reliable is this? For example, if intensive repeated surveying effort observers put in at Rufous Whistlers were recorded in 75 of 100 fixed sites over several years, and the collection of summer surveys within the catchment of the numerical information. This makes it possible to see Murrumbidgee River, and in 10 of 100 winter how well changes in the ‘reporting rate’ of a species surveys in the same region, it might be concluded in a region reflected changes in abundance of that that there were more Rufous Whistlers in this region in the summer – but perhaps they were simply more widespread in summer and more concentrated in winter. We really need to estimate the relative number of individuals present during each period. The ABC surveyors did this, and so created a unique data set with which to examine the strength of this relationship between reporting rates and a species’ regional abundance. Peter Griffioen’s analyses revealed that, for most species, there was a very strong relationship

Figure 2 The relationship between the reporting rate and the abundance of between reporting rate the species in the region, as reported by the ABC and mean abundance Figure 2a contributors. (The average correlation coefficient (birds detected per hectare for 512 species sampled was 0.81 ± 0.17, calculated in a 20-minute survey), using the method of Nachman.5) The relationship based upon ABC data, for (a) Red Wattlebird, and was strong for most species examined, such as the (b) Straw-necked Ibis. Red Wattlebird (Figure 2a). The red lines represent 95 per cent confidence intervals. In other words, we can be 95 per cent certain that our estimate of this species’ abundance for a particular reporting rate lies between the two red lines. But the confidence intervals for species that can form large flocks (such as the Straw-necked Ibis, Figure 2b) are much further apart, so changes in reporting rate will not be a good predictor of changes in that Figure 2b species’ abundance. Australian Bird Count v

Regional changes in abundance Thanks to the sterling efforts of thousands of Information about the timing of movements is volunteers, Birds Australia and affiliated rarely obtainable from large-scale bird-banding. ornithological organisations possess some In a country the size of Australia, the chance of a extraordinarily large data sets. These include the bush bird that has been banded in one location first Atlas of Australian Birds, the NSW Atlas, and the Canberra Ornithologists Group’s data base. being recaptured (or the band recovered) in another With the computerisation of these data bases, they location is very small, since there are few people can now be combined to provide a very powerful and the area needing to be covered is immense. research tool. The core of this power lies in the For example, by 1995 about 270,000 Silvereyes huge number of surveys it represents – more than had been banded in Australia,6 but only 458 4.5 million records. (0.17 per cent) were recovered farther than 5 km from 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 other data bases, it is possible for the first time to discern regional changes in the abundances of species based upon large-scale changes in regional reporting rates. However, changes in reporting rates must be interpreted with caution, because they may also reflect seasonal changes in the conspicuousness or detectability of a particular species. For example, a species might be present in a region during the non-breeding season, but be hard to detect when not calling. Even so, for many species, major changes in reporting rate can tell us much about changes in abundance over time and space. This is the case for the Grey Fantail in eastern Australia (Figure 3 a–d). Most of the population appears to winter in northern , coastal and Cape York, but then largely abandons these regions in summer to breed in coastal New South Wales, and Tasmania. For the maps shown here, surveys conducted within 45 days either side of 8 March, 8 June, 8 September and 8 December have been pooled as ‘autumn’, ‘winter’, ‘spring’ and ‘summer’ respectively, with greater weighting being given to surveys carried out Above: In eastern Australia, closer to those central dates. many Grey Fantails appear to winter in northern New For some parts of the country it is possible to South Wales, coastal produce maps for every fortnight of the year, Queensland and Cape York, because of the huge number of surveys available. but then largely abandon Such a series of maps can then be arranged in these regions in summer to chronological order, and when run through on a breed in coastal New South Wales, Victoria and computer in quick succession produce remarkable Tasmania. animated depictions of the changes in distribution of the species as the year unfolds. Grey Fantails are a Left: Banding studies are striking example, as discussed above. This is the first not always useful for time the depiction of the scale and timing of such studying seasonal movements. By 1995 about large-scale movements has been possible. 270,000 Silvereyes had been banded in Australia, but Seasonal distributions only 32 were recovered in a The analysis of the ABC data is now giving us a short enough time to reveal much clearer picture of when and where birds are the timing of their movement. moving. Bird-watchers often have a good idea of Photos by Graeme when migrants come and go from their own local Chapman area, and discuss these events in newsletters and electronic media such as birding-aus. But now for the first time we can generate maps of such movements at the continental scale. vi Australian Bird Count

Figure 3 Eastern distribution of the Grey Fantail during ‘autumn’, ‘winter’, ‘spring’ and ‘summer’. Units are birds per hectare that might be detected in a 20-minute survey.

Autumn Winter Figure 3a Figure 3b

no data 0

0 ≤ 0.25 0.25 ≤ 0.5 0.5 ≤ 1.0 1.0 ≤ 2.0 > 2.0 Spring Summer Figure 3c Figure 3d Australian Bird Count vii

Sometimes the maps confirm what many have Grey Fantails appear to abandon south-eastern Above left: The seasonal known for years regarding the timing and location Australia for warmer northern regions in winter distribution maps have confirmed what many have of movements of some species, such as the (see Figure 3b), many do not. Are these individuals known for years about the Dollarbird, Shining Bronze-Cuckoo and Rainbow members of non-migratory sub-populations of the timing and location of Bee-eater (Figures 4–6). But in other cases, species, or are they a particular age-class of Grey movements of some unexpected or poorly documented seasonal Fantails (such as adults) that do not migrate? There species, such as the movement patterns have been detected. For is evidence that Grey Fantails and other species Rainbow Bee-eater. Photo by Graeme Chapman example, some field guides describe Richard’s Pipit favour drier, more open habitats in winter than in as sedentary, but the ABC and Atlas maps suggest summer. No doubt, dozens of similarly intriguing Above: Some field guides this species spreads in a south-easterly direction in puzzles will emerge as these maps and data are describe Richard’s Pipit as summer, increasing in abundance in Tasmania, examined more closely. These questions might well sedentary, but the ABC data Victoria and southern New South Wales (Figure 7). be important for the recognition and conservation and Atlas maps show that it spreads in a south-easterly Another example is the annual movement up and of sub-populations within larger species complexes. direction in summer. down the north coast of New South Wales and Photo by Dave Watts southern Queensland of the Scarlet Seasonal changes from controlled sites population (Figure 8). Much of the Golden Whistler One of the strengths of ABC data is that population appears to spread inland in winter, but comparisons can be made between identical sets of spends summer in the ranges or closer to the coast in sites surveyed at different times with known effort. eastern Australia (Figure 9). This means that we can check whether apparent These kinds of maps can also be used to identify trends in maps prepared using Atlas data might be regions in which migratory species are present all due partly to seasonal changes in observer behaviour year round – a circumstance that spawns an array of (for example, when bird-watchers visit the interior additional questions. For example, although many more in winter than summer). A summary table has viii Australian Bird Count

Figure 4 Eastern distribution of the Dollarbird during ‘autumn’, ‘winter’, ‘spring’, ‘summer’. Units are birds per hectare that might be detected in a 20-minute survey.

Autumn Winter

Figure 4a Figure 4b

no data 0

0 ≤ 0.25 0.25 ≤ 0.5 0.5 ≤ 1.0 1.0 ≤ 2.0 > 2.0 Spring Summer Figure 4c Figure 4d Australian Bird Count ix

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

no data

0

0 ≤ 0.1

0.1 ≤ 0.2

0.2 ≤ 0.4 0.4 ≤ 0.8 > 0.8

Winter Summer

Figure 5a Figure 5b

Figure 6 Eastern distribution of the Rainbow Bee-eater during ‘winter’, and ‘summer’. Units in all maps are birds per hectare that might be detected in a 20-minute survey.

no data 0

0 ≤ 0.25 0.25 ≤ 0.5 0.5 ≤ 1.0 1.0 ≤ 2.0 Winter Summer > 2.0 Figure 6a Figure 6b x Australian Bird Count

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 that might be detected in a 20-minute survey.

no data

0

0 ≤ 0.25

0.25 ≤ 0.5 0.5 ≤ 1.0

1.0 ≤ 2.0 > 2.0

Winter Summer

Figure 7a Figure 7b

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.

no data 0

0 ≤ 0.25 0.25 ≤ 0.5 0.5 ≤ 1.0

1.0 ≤ 2.0 > 2.0 Winter Summer Figure 8a Figure 8b Australian Bird Count xi

Figure 9 Eastern distribution of the Golden Whistler during ‘winter’, and ‘summer’. Units in all maps are birds per hectare that might be detected in a 20-minute survey.

no data 0

0 ≤ 0.1

0.1 ≤ 0.2

0.2 ≤ 0.4

0.4 ≤ 0.8 Winter Summer > 0.8 Figure 9a Figure 9b been constructed for selected species showing mean and Leaden Flycatcher: the last species in particular bird abundances in summer and winter, based is known to be a common winter visitor on Cape exclusively on sets of ABC sites surveyed in all four York. Winter exoduses from Tasmania were evident seasons (Table 2, see p. XII). The data were sorted by for the Flame Robin, Grey Fantail, Tree Martin, State, with the ACT grouped with New South Wales, Welcome Swallow, Striated and Silvereye, Queensland divided into north and south at latitude in contrast to the Golden Whistler and Spotted 25°S, and Western Australia divided likewise at Pardalote which showed no net seasonal change latitude 30°S. Each site was given equal weighting in in Tasmania. calculating means, regardless of how often it was In Western Australia, many species were more surveyed. These regions were then grouped further common in summer than in winter in the south, and after inspection of seasonal data for each species. in some cases the limited data from the north (Note that ABC data are based on a less compre- suggested a winter increase there (e.g. Western hensive set of sites and habitats than Atlas data, with and Richard’s Pipit, Table 2). Silvereyes some obvious biases, e.g. there were few sites in showed no net seasonal change in the south-west inland Australia, cleared pasture or extensive forests.) (Table 2), though we would expect them to move The data provide clear and controlled evidence between habitats within the region. Grey Fantails for winter declines of many common species in appeared to be more common in winter than summer southern Australia (especially Tasmania) and winter in southern Western Australia: sites near may increases of some of them in northern Australia attract a winter influx from wet forests in the far (Table 2). The limited data from the north suggest south-west, where fewer surveys were conducted. that summer departures of southern migrants were The State-based tabulation (Table 2) obscures greater from the and northern some known habitat shifts, often involving a winter Western Australia than from north Queensland. exodus from wet forests into drier habitats. For some However, often these species were numerous in species this involved westward extension of range in winter in far north Queensland, but the seasonal winter, clearly evident from Atlas maps (e.g. Golden pattern was obscured by the inclusion of sites further Whistler and ). south in this vast region. This may have applied to Some and were more species such as the Fairy Martin, Satin Flycatcher common in winter than in summer at most sites x11 Australian Bird Count

Species Region Summer Winter Table 2 Mean abundance of selected species by region in summer and winter. Figures are birds Azure Kingfisher NT, NQld, SQld 18 16 observed per hectare per 20–minute survey (x 1000). NSW, Vic 5 1 Black-faced Cuckoo-shrike NT + NWA 38 63 NQld + SQld 154 119 SWA 59 61 elsewhere 99 44 Dusky Woodswallow NQld + SQld 1 5 surveyed, as they tend to be summer visitors to NSW + Vic + SA 43 19 Tas 288 2 extensive forests (with relatively few ABC sites) and Fairy Martin NT + NWA 0 9 winter visitors to more accessible habitats. The well- NQld 249 207 known north–south migrations of Yellow-faced elsewhere 46 11 Golden Whistler NQld 34 15 Honeyeaters were clearly evident from New South SQld 98 133 Wales and Queensland data but further analysis is NSW + Vic + SA 66 57 needed to assess habitat shifts within Victoria and Tas 74 99 (Table 2). Grey Fantail NQld 18 411 NT + NWA 1 40 Additional statistical analyses based on habitats SQld 68 411 and bioregions are being carried out and there NSW + SA 168 159 remains great scope for other researchers to use the Vic + Tas 339 215 Leaden Flycatcher NT 32 87 data to answer questions of interest to them or to NQld 57 38 land managers. elsewhere 16 2 Magpie-lark NT 61 181 NQld 268 516 SQld 179 225 SOME MYSTERIES elsewhere 128 119 The ABC data set has not only solved some Rainbow Bee-eater NT 153 169 NQld 485 228 mysteries: it has created some too. Maps generated SQld 101 68 from combined ABC and Atlas data suggest that NSW + Vic + SA 37 6 Dusky Woodswallows were more common in Richard’s Pipit NT + NWA 1 21 summer than in winter through most of their eastern N,SQld + NSW + SA + Vic 7 6 Tas 11 0 range. They are clearly summer migrants in the Rose Robin SQld 3 17 south, but where do they go to in winter? The ABC NSW 1 9 data point to a winter increase in Queensland Vic 2 0 Rose-crowned Fruit-Dove NT + NQld + SQld + NSW 14 4 (Table 2), though only low numbers were recorded Rufous Fantail NQld + NT + NWA 7 50 there on ABC sites. Field guides give their view of SQld + NSW 23 3 winter range (e.g. Pizzey & Knight 19978), but do we Vic 7 0 Rufous Whistler NQld + NT 44 80 really know? Inland areas of Queensland clearly SQld 64 67 deserve further attention in the future. NSW + Vic + SA 117 7 Azure Kingfishers were recorded more often in Sacred Kingfisher NT + NWA 12 47 summer than in winter in southern mainland NQld 20 14 SQld + NSW + SA + Vic 44 3 Australia during the Atlas; but was this merely Scarlet Honeyeater S + NQld 38 160 because observers spent more time around rivers NSW 21 7 during summer? The limited ABC data also suggest Silvereye NWA + NT + N,SQld + NSW + SA 257 538 SWA 455 453 a summer increase on the sites surveyed in both Vic + Tas 280 198 seasons (Table 2). Spotted Pardalote NT + S,NWA + N,SQld + NSW + Vic 55 111 Rose-crowned Fruit-Doves were observed more Tas 147 141 Striated Pardalote NWA + NT + N,SQld + NSW 36 98 often in summer than winter throughout their tropical SA + Vic 162 150 or subtropical range, yet ABC–Atlas maps show a Tas 306 30 remarkable consistency in distribution across seasons Tree Martin NWA + NT + NQld 58 194 SQld + NSW + Vic + SA + SWA 144 117 (Table 2). Perhaps the ABC data reflect conspicu- Tas 41 0 ousness while breeding, or do birds move into more Western Gerygone NWA044accessible habitats in the humid summer season? SWA 192 138 Some unexpected trends emerged for species elsewhere 2 1 White-throated Gerygone NQld 19 46 generally regarded as sedentary (Table 2). For SQld 20 16 example, there was an apparent summer increase of NSW + Vic 19 1 in the Northern Territory and a NWA + NT + NQld 77 177 SQld + SA 112 115 winter increase of Magpie-larks in the Northern NSW + Vic 173 82 Territory and north Queensland (as also reported Yellow-faced Honeyeater NQld 19 14 in the first Atlas). Willie Wagtails were more SQld + NSW 101 389 Vic + SA 132 151 common in summer than winter at sites surveyed in Victoria and NSW–ACT, and vice versa in north Notes: Queensland. Long-distance movement has never 1 summer = 8 Dec ± 45 days; winter = 8 June ± 45 days 2 Table is based on data from 54 sites counted in all four seasons in northern Queensland, 88 in been suspected in this species, so the results may southern Queensland, 301 in NSW–ACT, 133 in Victoria, 39 in Tasmania, 72 in South Australia, reflect local habitat shifts occurring independently 94 in southern WA, 9 in northern WA and 23 in NT. in each region – or do they? Further investigation is 3 Each site was given equal weighting in calculating means, regardless of how often it was surveyed. in order. Australian Bird Count xiii

Long-term changes Far left: Dusky The period covered by the ABC was too short to Woodswallows are clearly detect long-term nation-wide trends. Year-to-year summer migrants in the south, but where do they changes were examined for 12 selected species, using go to in winter? Inland data from sites counted in each of the five years from areas of Queensland could 1990 to 1994. Three woodland birds thought to be be the answer. declining – Scarlet Robins, Hooded Robins and Photo by Rob Drummond Speckled Warblers – were included in this group.9,10 Above: The Magpie-lark is Mean densities of two woodland birds (Scarlet usually thought of as a Robins and Hooded Robins) appeared to decline sedentary species, but the gradually from maximum levels in 1990. However, ABC data indicate a winter the density of Speckled Warblers, another ground- increase of Magpie-larks in foraging bird of the open woodlands, appeared to the Northern Territory and north Queensland. increase over the same period. These opposing results Photo by Graeme Chapman imply a need for very long-term data sets to detect all but the most dramatic changes in bird populations Left: Very long-term data on a national scale. are needed to detect all but the most dramatic changes ONSERVATION IMPLICATIONS in bird populations on a C national scale, especially for Knowing when and where birds move around the woodland birds that appear country is fundamental to the sound management of to be declining, such as the their habitat. Some areas, such as river courses or Hooded Robin. large remnants of native vegetation, may be identified Photo by Graeme Chapman as being significant migration routes or stopover points in the movement patterns of several species. For example, when examining the seasonal maps for the Red-tailed Black-Cockatoo in inland New South Wales, seasonal movements by cockatoos are clearly xiv Australian Bird Count

occurring along the Darling River (Figure 10). This quantitative evidence of the importance of such critical features of the landscape should strengthen the case for their preservation and careful Right: In inland New South management, and highlight the importance of these Wales, Red-tailed Black- Cockatoos appear to move life-giving arteries in an arid landscape. along the Darling River. The Birds Australia and its affiliates have been co- quantitative evidence ordinating surveys such as the ABC for more than provided by the ABC data 20 years: a period during which the Australian highlights the importance landscape has undergone some major changes. As data of such life-giving arteries in an arid landscape. from the current New Atlas project accumulate, comparisons will be made with the older data sets. Below: The ABC data will Many important conservation-related questions will help us to document the be able to be addressed. For example, we will be able spread of introduced to identify those species that have suffered significant species, such as the Laughing Kookaburra in reductions in their range or abundance in the 20 years the west. since the first Atlas (1977–81). We will also be able to Photos by Dave Watts document the spread of introduced species such as or in the east, or Laughing Kookaburra in the west, or the degree to which native ‘pest’ species such as Noisy Miners and Pied Currawongs are increasing in abundance or range. The ABC data will be an important stepping stone between the two field Atlases. The first Atlas led to many major conservation initiatives for Australian birds. We anticipate that our ability to identify conservation priorities will be far greater in the next few years as the New Atlas project takes another snapshot of the state of our birds, which we can then compare with the picture produced as a result of the efforts of past Atlassers and ABCers (or ‘Cabbies’ – Counters of Australian Birds). We hope that this direct link between the data collected by volunteers and conservation initiatives will stimulate even more people to get out there surveying our amazing birdlife, and analysing results.

Further information

For further analysis using Atlas or ABC data, see the Birds Australia website: www.birdsaustralia.com.au or contact research staff at Birds Australia, or the authors: Dr Mike Clarke, Dept. of Zoology, La Trobe University, Bundoora, Vic 3083; email: [email protected] Peter Griffioen: email: [email protected] Richard Loyn, Arthur Rylah Institute (Dept. of Natural Resources and Environment), 123 Brown St, Heidelberg, Vic. 3084; email: [email protected] ABC results have been used for a number of research and conservation purposes (e.g. Griffioen 1996). A more complete set of results has been placed on the Australian Broadcasting Corporation (the other ABC) website for Birds Australia at www.abc.net.au/birds. Australian Bird Count xv

Figure 10 Distribution of the Red-tailed Black-Cockatoo in New South Wales and southern Queensland during ‘winter’ and ‘summer’. Units in all maps are birds per hectare that might be detected in a 20-minute survey.

no data 0

0 ≤ 0.25 0.25 ≤ 0.5 0.5 ≤ 1.0

1.0 ≤ 2.0 Winter Summer > 2.0 Figure 10a Figure 10b

A CKNOWLEDGEMENTS

Main thanks to the 1000+ volunteers who contributed their time and expertise to collecting field data for the ABC and associated projects (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 Phillip Moors, Barry Baker, Brian Snape, Dr David Baker-Gabb, Dr Mike Newman, and others. The project was co-ordinated by Dr Stephen Ambrose throughout its field phase, ably assisted by volunteers in Sydney and Melbourne. This work was overseen by a steering committee of Dr Phillip Moors and then Dr David Baker-Gabb (Chairs), Barry Baker, Marilyn Hewish, Richard Loyn and Bruce 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 from The 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. Australian Bird Count

REFERENCES 1 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 and Movements of Australian Birds: Workshop Report, RAOU Report 28, RAOU, Moonee Ponds. CONSERVATION THROUGH KNOWLEDGE 3 Hewish M. & Loyn R. H. 1989, Popularity ACN 004 076 475 and Effectiveness of Four Survey Methods for 415 Riversdale Road, Hawthorn East, Vic. 3123 Monitoring Populations of Australian Land Birds, Tel: (03) 9882 2622; Fax: (03) 9882 2677 RAOU Report 55, RAOU, Moonee Ponds. Email: [email protected] 4 Loyn R. H. 1986, ‘The 20 minute search – a Birds Australia Home Page: http://www.birdsaustralia.com.au simple method for counting forest birds’, Founded in 1901, Birds Australia (Royal Australasian Ornithologists Union) is Australia’s oldest national Corella, vol. 10, pp. 58–60. conservation organisation, dedicated to the study and 5 Nachman, G. 1981, ‘A mathematical model of conservation of native birds and their habitat. New members the functional relationship between density are welcome. and the spatial distribution of a population’, The Australian Bird Count was generously supported by the Journal of Ecology, vol. 50, pp. 453–60. Australian Nature Conservation Agency (now Environment 6 Baker G. B., Dettman E. B., Scotney B. T., Australia) and BP Australia. Hardy L. J. & Drynan D. A. D. 1997, Report on the Australian Bird and Bat Banding Scheme, 1995–96, Environment Australia, Canberra 7 Griffioen P. 1996, Investigation of bird movements using the Australian Bird Count: A pilot study based on the Silvereye, Zosterops lateralis, Grad. Dip. Thesis, Dept. of Zoology, La Trobe University, Bundoora. 8 Pizzey, G. & Knight, F. 1997, The Field Guide to the Birds of Australia, Angus & Robertson, Funding for the publication of this supplement was generously Sydney. provided by the Wettenhall Foundation. 9 Robinson, D. 1993, ‘Vale Toolern Vale: the loss of our woodland birds’, Wingspan, vol. 9, pp. 1–3, 20–21. 10 Robinson, D. & Traill, B. J. 1996, Conserving Woodland Birds in the Wheat and Sheep Belts of Southern Australia, RAOU Conservation Statement No. 10, Supplement to Wingspan, vol. 6, no. 2. Wingspan is the quarterly membership magazine of Birds Australia. Additional copies of this supplement Cover photo: in the Mallee Graeme Chapman are available from the National Office. Inset left: Striated Pardalote Rob Drummond Inset right: Scarlet Robin Dave Watts Printed on recycled paper.

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