Breeding biology, adult survival and territoriality of the white-browed treecreeper (climacteris affinis) in north-west Victoria, Australia

This is the first study to present empirical data describing the social organisation and breeding biology of the White-browed Treecreeper (Climacteris affinis). The species is typical of many small Australian passerines in that it has high annual survival (~80%), small clutches (mean = 1.95 ± 0.05), long breeding seasons (eggs laid August to November) and long incubation (17–18 days) and nestling periods (25–26 days), corrected for body weight. Reproductive effort is modified in response to variation in climatic conditions by adjusting the commencement of breeding and number of clutches laid per season, which is facilitated by an extended breeding season. White-browed Treecreepers occupied relatively large (mean = 8.4 ± 0.8 ha), all-purpose territories throughout the year. However, unlike many group territorial birds, territory size was not related to the number of occupants. The role of food limitation and climatic variability in relation to territory dispersion and life-history traits is explored. Facultative cooperative breeding was confirmed. Cooperative groups were formed through male philopatry, with usually only one, but up to three, male helpers present in a moderate fraction (35%) of breeding units. Thus, all species of Climacteris are now confirmed as facultative cooperatively breeding species, which provides further evidence for the aggregation of cooperative breeders at the generic level in mixed (i.e. cooperative and pair breeders) phylogenetic clades. In C. affinis, males may attain breeding positions through inheritance of their natal territory or by filling vacancies in nearby territories. Females obtained breeding positions by ‘floating’ as non-breeding residents in established territories, waiting for a vacancy to arise.

Determining the sex of Little Penguins (Eudyptula minor) in northern Bass Strait using morphometric measurements

In avian species with no obvious differences in plumage or body size between the sexes, such as penguins, discriminant function analysis (DFA) of morphometric measurements that display sexual dimorphism can provide a simple and rapid means of determining sex in the field. Like most other penguin species, the Little Penguin (Eudyptula minor) displays sexual dimorphism in bill shape and size. In the present study, discriminant functions (DFs) were developed for sexing adult Little Penguins at two colonies in northern Bass Strait, Victoria, Australia, and their accuracies were compared with those obtained previously in other parts of the species' range. Backwards stepwise DFA indicated that birds at Phillip Island can be sexed with an accuracy of 91% using a single measurement of bill depth (>13.33 mm classed as males). Similar analyses at Gibson Steps produced a DF incorporating bill length, bill depth and head length [although the model with the greatest accuracy when applied to birds from Phillip Island (91%) also contained only bill depth]. Published DFs derived in New Zealand had accuracies of 50–85% when applied to birds from Phillip Island and Gibson Steps, supporting earlier suggestions that DFs are not applicable across subspecies of the Little Penguin. In contrast, there was little difference between the accuracy of the DFs in the present study and that previously derived for the same subspecies in Tasmania when applied to birds from Phillip Island (89%) and Gibson Steps (92%). However, as the degree of variation in bill size within a subspecies is unknown it may still be prudent to derive colony-specific DFs.

Habitat use and distribution of the beautiful firetail (stagonopleura bella) in foothill forests of the Victorian highlands, Australia

The Beautiful Firetail (Stagonopleura bella) is an uncommon, granivorous finch from coastal south-eastern Australia, with a distribution extending from mid-coastal New South Wales to south-eastern South Australia, including Tasmania. This paper presents a quantitative assessment of habitat use by the Beautiful Firetail based on data collected from 30 paired riparian and non-riparian sites in the foothill forests of the Victorian Highlands, Australia. The Beautiful Firetail occurred in two of the three forest blocks surveyed and was found almost exclusively at riparian sites. The Beautiful Firetail was most likely to occur at riparian sites on the coastal fall of the ranges at sites with high sedge cover and low cover of shrubs and bare ground. The species occurred at low densities (0.10–0.19 individuals ha^–1) throughout the year. Records from the Atlas of Victorian Wildlife were used to describe the distribution of Beautiful Firetails in Victoria. Notable observations inland of the Great Dividing Range were recorded during the present study. Further study is required to understand the ecological requirements of the Beautiful Firetail throughout its range.

Biometrics and sexing criteria of the yellow-faced honeyeater lichenostomus chrysops

Morphometric data on 99 adult and 13 juvenile Yellow-faced Honeyeaters Lichenostomus chrysops that were independently sexed using molecular techniques were analysed to investigate size dimorphism between the sexes. Our results support previous studies that have demonstrated Yellow-faced Honeyeaters are sexually dimorphic in size, with males being the larger sex. Discriminant analyses of morphometric data were used to develop a simple method for sexing adult Yellow-faced Honeyeaters in the hand. As five observers collected the measurements our sexing criteria are conservative and should have wide application for field ornithologists working on the species.

Methods for aging and sexing the Black-eared Miner, Manorina melanotis, and Yellow-throated Miner, M. flavigula

Morphometric data on 92 Black-eared Miners and 47 Yellow-throated Miners that had been independently sexed using molecular techniques were analysed to investigate size dimorphism between the sexes. We found that both species are sexually dimorphic in size, with males being the larger sex. Discriminant analyses of morphometric data were used to develop a simple method for sexing both species in the hand. Additionally, alula shape was consistent with other methods that we applied for ageing individuals. Sex-specific size differences between Black-eared and Yellow-throated Miners detected here add further support to the contention that they represent different taxa. The application of these sexing and ageing techniques for both species of mallee miner will improve ongoing field management of the endangered Black-eared Miner.

Detection and habitat use of the rufous bristlebird (Dasyornis broadbenti) in coastal heathland, in south-western Victoria, Australia

The Rufous Bristlebird (Dasyornis broadbenti) is a sedentary, ground-dwelling passerine of southern Australia, which is listed as nationally vulnerable, and as near-threatened (lower risk) in Victoria. The species inhabits a variety of vegetation, including shrub thickets in coastal gullies to heathlands on limestone cliffs. This study aimed to assess the size, distribution and habitat use of a population of the subspecies D. b.  broadbenti at Portland in south-western Victoria. Monthly surveys (2002–03) were conducted on foot for 1 h after official sunrise and 1 h before official sunset, and presence of Bristlebirds recorded using vocalisations and sightings. Observations outside of the survey times were also recorded to estimate the size of territories and core area of occupancy. To quantify habitat preferences, vegetation composition and structure were measured in areas where Bristlebirds were present, as well as surrounding areas where they were not detected. The population in the survey areas was estimated at between 70 and 86 individuals in the 170-ha survey area. The estimated size of territories of eight selected pairs of Bristlebirds ranged from 0.5 to 3 ha, with core areas of occupancy ranging from 0.2 to 0.6 ha. During the nesting season (August November) Bristlebirds were detected at greater frequencies in the core area of occupancy within each territory. Significant associations were found between the presence of Bristlebirds and floristic associations dominated by the native environmental weeds Acacia sophorae and Leptospermum laevigatum. Bristlebird presence was significantly positively correlated with increasing vegetation density in the mid-canopy level (80–120 cm) indicating that vegetation structure is a key factor in habitat use.

Climatic variation and breeding in the Australian magpie (Gymnorhina Tibicen) : a case study using existing data

To anticipate the effects of climate change on Australia’s avifauna, it is first necessary to understand the current effects of climate (including climate variability) on life histories, and to examine the scope and nature of existing data that may provide the necessary historical context to anticipate the effects of climate change. This study examines naturally occurring geographical gradients (altitude, latitude) and the Southern Oscillation Index (SOI) as integrated measures of climate. These are then compared with the timing and ‘amount’ of breeding recorded for the Australian Magpie (Gymnorhina tibicen) using data from Birds Australia’s Nest Record Scheme and Atlas of Australian Birds, the NSW Bird Atlassers Inc.’s NSW Bird Atlas, and the Canberra Ornitholgists Group’s Garden Bird Survey. For this common, easily identified species, these data suggest links between Australian Magpie breeding and all three environmental variables. Breeding became later as altitude increased, the proportion of breeding records increased from north to south, and years of high SOI corresponded to more (and earlier) breeding in this species. That annual climatic fluctuations have a direct, immediate and substantial effect on breeding in the Australian Magpie, particularly on the amount of breeding that occurs, implies that longer term changes in climate will have substantial impacts on populations. Results were not solely temperature-driven, which makes predicting climate change impacts difficult. For rainfall, predictions are far less precise and regional variation is higher. The results also highlight the potential and limitations of current survey techniques for documenting the impacts of climate change on birds; in particular, the Nest Record Scheme does not measure the amount of breeding that occurs, but a useful index of this can be derived from bird atlassing data

Preliminary investigation of the costs of incubation in the Australasian Gannet (Morus serrator) breeding in Port Phillip Bay, Victoria

To optimise lifetime reproductive success, individuals must balance current reproductive effort against future reproductive prospects. In birds, incubation and chick-rearing must involve costs, and manipulation of the length of incubation offers an insight into some costs affecting adults. An experiment was conducted at a colony of Australasian Gannets in Port Phillip Bay, Victoria, in which length of incubation was manipulated so that some adults experienced short (10–20 days duration), long (70–80 days) or normal (~45 days) incubation periods. Adults with a manipulated incubation period did not show significant differences in weight change (taken here to reflect cost) during incubation or chick-rearing compared with controls. Manipulation of length of incubation did not significantly affect the hatching success or the growth rate of chicks involved and is not, therefore considered to impose an increased reproductive cost. This suggests that the Australasian Gannet has the capacity to maintain body condition and successfully rear young despite modified duration of incubation.

Distribution and abundance of seabirds in Western Port, Victoria

The distribution, abundance and biomass of seabirds in Western Port, Victoria, were surveyed between April 1991 and August 1994. Individuals were counted along an 81-km series of transects from a boat at approximately monthly intervals. A total of 25 seabird taxa were recorded, of which 18 and 15 were common to those recorded by an earlier study in Port Phillip Bay and waters south of Phillip Island, respectively. The most numerous species by far was the Short-tailed Shearwater (Puffinus tenuirostris) followed by the Silver Gull (Larus novaehollandiae), Little Penguin (Eudyptula minor) and Crested Tern (Sterna bergii). Distribution within Western Port was not uniform, with pursuit divers such as cormorant and grebe species being recorded mostly in the shallow Eastern Arm. In contrast, surface-seizing (e.g. albatrosses), surface-plunging (e.g. Crested Terns), shallow-plunging (Australasian Gannet, Morus serrator) and pursuit-plunging (e.g. shearwaters) species predominated in the deeper Western Arm of Western Port. These species were also seasonally abundant, with peak numbers for most occurring in late summer–early autumn, which coincides with the reported influx of juvenile clupeoid fish into Western Port. Average biomass (686 ± 395 kg) comprised mostly Short-tailed Shearwaters, Little Penguins and Pied Cormorants (Phalacrocorax varius). Biomass density (8.5 kg km^–2) was similar to that reported for Port Phillip Bay (8.1 kg km^–2) but lower than off the southern coast of Phillip Island (9.9 kg km^–2).

A review of terrestrial bird atlases of the world and their application

We reviewed 272 bird atlases (standardised surveys intended to document the distribution of birds) from around the world. Atlases we located were conducted in 50 countries from six continents with most (82.4%) from Europe and North America. Atlases were mostly run by ornithological societies (67.1%), had amassed at least 27.9 million records of birds over an area roughly 31.4% of the land area of the Earth, and had involved at least 108 000 contributors. They had a modal data collection period of 4 years (some ran over several decades) and varied greatly in scale, covering local areas to entire continents (21 km² – 10 390 000 km²); atlases that covered larger areas involved more observers and generated more records. Most atlases (88.3%) were constrained to particular seasons, and most of these focussed on the main local breeding period (81.0%). Spatial sampling units ranged from 0.02 km² (2 ha) to 3092 km² and temporal units of sampling varied from 20 minutes to several years. Little information is available on the application of data generated by atlases. We focussed on five major atlases for which information was available. We located 97 scientific publications drawing on data from these five major atlases; papers most frequently focussed on bird distribution (26.8%), ecology (20.6%) and land-use planning (17.5%). Atlas books were cited often, 7–31 times per year. Provision of data to third parties from two major atlases (one from Australia and one from Britain and Ireland) was frequent and remarkably similar. Data were requested mostly for environmental impact studies (almost half of all requests), conservation policy and planning (~20%), research (~20%) and other mapping (~13%). Despite the uses we describe, atlas data seem under-utilised.

Spatial and temporal variation in the breeding of Masked Lapwings (Vanellus miles) in Australia

Spatial and temporal variation in the breeding of Masked Lapwings (Vanellus miles) in Australia were examined using data from Birds Australia’s Nest Record Scheme (NRS; 1957–2002), the Atlas of Australian Birds (1998–2006), and climatic data (1952–2006). Breeding in north-western Australia was concentrated in summer, while in other regions the peak of breeding occurred during spring. Breeding success varied between regions and years but was generally highest in Tasmania. Clutch-size (mean 3.57 eggs ± 0.033 s.e., n = 549 clutches) did not vary regionally or temporally. In the north-east, breeding became earlier over time (~1.9 days per year, NRS), while in the south-east, breeding became later (~0.9 days per year); in other regions temporal trends were not evident. Only Tasmania showed a significant temporal change in breeding success (decrease of ~1.5% per year). All regions experienced warming climates, and annual rainfall increased in north-western regions and decreased in eastern regions. There were weak or no relationships between the amount or success of breeding, clutch-size and the climatic variables considered (with the possible exception of Tasmania), suggesting either that data limitations precluded us from detecting subtle effects or that Masked Lapwings have been little influenced or are resilient to changes in climate over most of their range.

Range-wide phylogeography of the Little Penguin (Eudyptula minor): evidence of long-distance dispersal

The Little Penguin (Eudyptula minor), a colonial-nesting seabird that is widespread in New Zealand and southern Australia, has high dispersal potential but exhibits regional variation in morphology, coloration, and breeding phenology. We present a distribution-wide survey of mitochondrial DNA variation in the Little Penguin to document phylogeographic relationships and genetic structuring and to test for concordance with intraspecific taxonomy. Phylogeographic structuring was absent among Australian colonies (27 localities, 94 individuals), but the distribution of haplotypes among colonies was significantly nonrandom (ϕST = 0.110, P < 0.01). The Australian individuals exhibited close phylogenetic relationships with a subset of New Zealand birds (4 localities, 22 individuals), whereas the remaining New Zealand birds (20 localities, 106 individuals) were phylogenetically distinct, with ≥7% sequence divergence, and exhibited greater levels of genetic variation and geographic structuring (ϕST = 0.774, P < 0.05). These patterns are consistent with earlier suggestions of an origin in New Zealand followed by recent colonization of Australia and back-dispersal to New Zealand. Extinction and re-establishment processes may have been important factors in the development of genetic structuring across a range of spatiotemporal scales. The genetic data are consistent with suggestions that a single subspecies exists in Australia, but not with the subspecies distributions within New Zealand that have been suggested on the basis of morphology and coloration.