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The Lovely Fairy-Wren (Malurus amabilis) is endemic to the wet tropics of Australia and is one of 11 species in the genus Malurus. Despite the large number of studies on fairy-wrens, little is know...

Phylogeny, ecological environment, social organisation, and mating system are expected to affect degree of female ornamentation, either directly or indirectly, but our understanding of how female ornaments respond to these forces remains incomplete. This article evaluates the evolutionary history and adaptive significance of three putative ornaments – plumage colouration, bill colouration and tail-length – in female fairy-wrens. Despite considerable research on these traits in male fairy-wrens, they have yet to be studied in any detail in females. Phylogeographic analyses in combination with life-history data suggest that female plumage colouration and bill colouration are under active selection, independent of that experienced by males. Social organisation and mating system, as mediated by ecological environment, may shape degree of ornamentation in these traits among females. In contrast, tail-length appears to be driven directly by natural ecological selection imposed by environmental conditions, leading to parallel trait evolution among the sexes within each species. More refined comparative and population-level investigations of adaptive consequences and proximate mechanisms are future research priorities. The study of female fairy-wrens holds great promise to advance our collective understanding of how the ecological environment interacts with sexual selection and social competition to shape ornament evolution in complex social organisms.

Cooperative breeding among birds was first discovered in the genus Malurus (Maluridae), the fairy-wrens. Cooperative care arises because male, and sometimes female, offspring remain in their natal territory and help the adults rear offspring. Early uses of data from Superb Fairy-wrens (Malurus cyaneus) to illustrate how kin altruism can explain helping behaviour were based on flawed assumptions. Most importantly, high rates of extra-group mating mean that the helpers often assist adults to which they are unrelated. However, measuring the costs and benefits of altruism has also proved difficult. Helping behaviour and its outcomes among species of Malurus are surprisingly diverse, despite similar founding conditions for cooperative breeding. First, species differ in whether help provides fitness benefits, in the recipients of those benefits, and whether benefits are immediate or deferred. Second, species vary greatly in whether females are philopatric and the extent to which female auxiliaries (supernumeraries), when present, provide care. Finally, male auxiliaries are much less sensitive to the needs of the brood than females. In this review we show that these three aspects of helping behaviour lack compelling explanations. We develop hypotheses to explain each phenomenon. Distinguishing among these hypotheses will greatly enhance our understanding of the remarkable social system of Malurus, and inform the study of cooperative breeding and sexual conflict in general.

Seasonal breeding plumage of male fairy-wrens (Malurus spp.) shows significant inter- and intra-specific variation in several potential signalling components that we systematically review here. There is extensive colour variation in the genus, possibly related to variation in visual sensitivity. In many species, males can delay development of their first complete breeding plumage for one or more years, although males in more complete breeding plumage appear to be reproductively more successful. An additional sexual signal, and an evolutionary innovation, is the timing of the pre-breeding moult. A mechanism regulating this moult is testosterone, which can stimulate initiation of moult and development of male breeding colouration and is presumably required for maintenance of the breeding plumage. Males undertake pre-breeding moult earlier as they age, and early pre-breeding moult appears selected by female choice for extra-pair mates. Few studies have addressed variation in colour quality or the role of plumage in aggressive interactions. Condition-dependence of moult or breeding plumage has not been experimentally investigated. We argue that the genus is particularly suited to comparative analyses, as it provides informative contrasts in colour, plumage development, patterns of moult, colour vision and mating system, offering many exciting opportunities for testing evolutionary theories on function and maintenance of sexual signals.

Fairy-wrens (Malurus) are socially monogamous and yet exhibit among the highest rates of extra-pair paternity (EPP) known in passerine birds. Here, we review patterns of EPP in fairy-wrens and their allies (Maluridae), and discuss the causes and evolutionary consequences of multiple mating in this group. Rates of EPP vary widely across species, but correlate strongly with relative testes mass suggesting that testes mass can be used as a proxy for EPP in comparative studies. With respect to variation in EPP, there appear to be consistent habitat differences between the subfamilies of Maluridae that may contribute to the observed inter-specific variation in rates of EPP, and specific habitat requirements of some species may influence patterns of paternity between species of Malurus. Within species, however, there is equivocal evidence for a role of group size influencing rates of EPP. Regardless of the causes of variation in EPP, available evidence suggests that female fairy-wrens may benefit from extra-pair matings through indirect genetic benefits, such as inbreeding avoidance and choice of high-quality males (i.e. good genes). Using Bayesian modelling, we show that the ancestral state in Australian malurids is one of low sperm competition, and that, in general, increased levels of sperm competition (and hence EPP) are a derived condition in this family. Given the broad range of levels of sperm competition in this family and the relationship between relative testes mass and EPP, we suggest that the Maluridae are a model system for studies of EPP and sperm competition.

Fairy-wrens (genus Malurus) maintain territories year round, and breed cooperatively, with all members of the social group provisioning young. Despite living with several adult males, the breeding female typically cuckolds all of them, seeking fertilisations from extra-group males that provide no care to her offspring, instead caring for the young reared on their own territory. We trace the evolutionary origins and persistence of this extraordinary combination of traits. We argue that the high rate of infidelity in some fairy-wrens facilitates social pairing among nuclear family relatives, rather than being an evolutionary response to avoid inbreeding. It seems likely that females mate with extra-group males to improve the genetic quality of their offspring. The ability of males to maintain breeding plumage for long periods is the primary criterion for female choice; only older males can do so. Several features of the mating system undermine the accuracy of female choice, and low-quality males exploit this uncertainty. Extra-group matings by low-quality males can help stabilise the mating system but may leave it vulnerable to collapse under certain circumstances. Nonetheless, sexual selection in most species is very strong, confirming the utility of fairy-wrens as model organisms for the study of mate choice and intersexual selection.

The conservation status of many birds in Australia has been deteriorating in response to human activities. Changestoland-managementpracticesarerequiredtohaltdeclinesbut,inmanycases,thecausalmechanismsofdeclinesare poorlyknownandsoitisdifficulttoprovideappropriatemanagementdirectives.Ofthe23AustralianspeciesofMaluridae, 12haveinfrataxathatmeetthecriteriaforinclusionwithinanIUCNRedListcategory.Thefamilypossessescharacteristics thatmakeitidealforresearch relevanttoimprovingconservationoutcomesfortheMaluridaeandotherthreatenedtaxa:the family is widely distributed, has been exposed to the varying pressures that operate in diverse habitats across Australia, and infrataxahavebroadlysimilar ecologiesandyetdisparateconservationlistings.Herewedescribe theconservationstatusof thetaxawithintheMaluridaeandoutlinehowthefamilycanbeusedasmodelstotestmechanismsassociatedwithdeclines andfordevelopingconceptstoenhanceconservationmanagement.Wearguethatdisparateresponsesofsympatricmalurids tothesameland-management regimescanbeusedtoidentifycharacteristicsthatmakespeciesvulnerabletoenvironmental pressures.Quantitativeinsightsintohowmaluridsrespondtothreateningprocessesmayprovidedirectivesformanagement of a range of threatened species. Additional keywords: Amytornis, fairy-wren, emu-wren, grasswren, land management, Maluridae, Malurus, Stipiturus. Received 1 September 2012, accepted 22 February 2013, published online 15 August 2013

Bird communities in suburban habitats are dominated by generalist species and tend to have fewer specialist species sensitive to disturbance. Superb (Malurus cyaneus) and Variegated (M. lamberti) Fairy-wrens are morphologically and ecologically similar but differ in the degree to which they occupy suburban habitats. The species often occur in sympatry in natural habitats but in suburban habitats Superb Fairy-wrens are much more common than Variegated Fairy-wrens. We compared the characteristics of the habitat of both species in natural and suburban areas to investigate whether habitat requirements differed between the species, and which may explain observed patterns of abundance. Patch-level vegetative and disturbance-related habitat characteristics of territories were compared to those of non-territories in natural and suburban habitats. In natural habitats, Superb Fairy-wrens occupied more disturbed patches than Variegated Fairy-wrens. Vegetated drainages and patches of weedy remnant vegetation were important habitats for suburban Superb Fairy-wrens, which also tolerated the presence of humans whereas Variegated Fairy-wrens were particularly sensitive to human presence. A better understanding of the factors affecting the abundance of the more sensitive native species in suburban areas, such as Variegated Fairy-wrens, may inform conservation actions to enhance suburban biodiversity.

The Superb Fairy-wren (Malurus cyaneus) is a model system in which to study cooperative breeding and extra-pair paternity. Previous studies in this species have shown that 61-76% of nestlings were extra-pair young and 92-95% of nests contained at least one extra-pair young. Furthermore, the probability of extra-pair paternity was higher when auxiliary males were present. We studied group size and extra-pair paternity in South Australia where, unlike other study sites, auxiliary males were relatively uncommon: 16% of nests had one auxiliary male compared to 37-80% with at least one auxiliary per nest in other studies. We predicted a lower incidence of extra-pair paternity, given the shortage of auxiliary males. Our results did not support this prediction: we found extra-pair paternity among 67% of nestlings and 83% of nests.

Effective monitoring techniques are vital to understanding a range of behaviours and their consequences for evolution of life histories. Video and photographic monitoring is regularly used but rarely with audio monitoring even though it can identify birds or predators off-camera, and detect alarm calls and songs. We developed a 4-channel audio-visual recording system to continuously monitor the nests of Superb Fairy-wrens (Malurus cyaneus). This innovative system worked autonomously for 3 days and identified repeat visits by some predators, detected nest predation by Grey Currawong (Strepera versicolor) and two rodents, and provided new insights into nest defence, provisioning rates, vocalisations of parents and nestlings and interactions between them.

Urbanisation has created an environment with a broad spectrum of habitats of differing quality for birds. Understanding habitat characteristics is necessary for effective conservation of species in...

In birds, several features of male reproductive anatomy vary with the degree of promiscuity and the intensity of sperm competition. We describe the male reproductive anatomy of the Southern Emu-wren (Stipiturus malachurus) and the Striated Grasswren (Amytornis striatus) in the context of sperm competition. Male Southern Emu-wrens exhibited a very low relative testes size of just 0.6% of male body mass, lacked a cloacal protuberance and possessed a relatively small seminal glomera containing an average of just 12.6 × 106 sperm. Male Striated Grasswrens exhibited relatively small testes, comprising 1.78% of male body mass, and small cloacal protuberances. The relative size of the seminal glomera was also small and seminal glomera contained an average of 42.5 × 106 sperm. When compared with the well-studied fairy-wrens (Malurus) and based on male reproductive anatomy, it appears that emu-wrens experience a relatively low level, and grasswrens an intermediate level, of sperm competition.

Understanding patterns of adaptive divergence is a cornerstone for understanding the process of speciation. The theory of ecological speciation predicts that natural selection shapes adaptive divergence. In this observational study, we examined the first phase of ecological speciation, namely adaptive divergence in foraging behaviour and morphology across populations (island and mainland sites) of the sexually dimorphic Superb Fairy- wren (Malurus cyaneus) that have been separated for approximately 9000 years. Current island theory predicts larger body-size in island species, as well as more generalist foraging and occupation of a wider ecological niche that is favoured by large body-size. We examined the vegetation structure across replicate study areas on Kangaroo Island and the mainland Mount Lofty Ranges in South Australia and found significant differences in vegetation structure important for Superb Fairy-wrens (percentage bare earth, shrub size and shrub abundance). Compared with mainland birds, island birds of both sexes: (1) occupied a wider niche breadth; (2) were significantly larger in body-size; and (3) varied less in morphology. Between the sexes: (1) there were few inter-sexual foraging differences; (2) males had a larger body-size and bill-length at both island and mainland locations; and (3) females had larger bill-width and bill-depth at both locations. These findings support the hypothesis of adaptive divergence in this species, with evidence that vegetation structure is important in their foraging behaviour and affects their morphology across locations (niche breadth was potentially favoured by a different interspecific community). The lack of consistent sexual differences in foraging ecology suggests that the patterns of sexual dimorphism may be shaped by reproductive roles rather than vegetation structure in this species. The categorisation of the Kangaroo Island population as a separate subspecies (M. c. ashbyi) is supported by these findings.

Superb, Malurus cyaneus, White-winged, M. leucopterus, and Variegated, M. lamberti, Fairy-wrens co-existing in a semi-arid environment at Booligal, New South Wales, partitioned their use of space. During drought, territories overlapped more than in good years. White-winged Fairy-wrens spent the most time sitting, showed the highest preference for sitting in bushes and allopreened the most. Superb Fairy-wrens foraged the most on the ground, moved up and down to different foraging stations the most rapidly and had the widest variety of foraging stations. White-winged Fairy-wrens foraged mostly on the outer parts of bushes; Variegated Fairy-wrens foraged on the innermost parts of bushes and spent the longest at a foraging station. White-winged Fairy-wrens flew the furthest to a new foraging site. When niche breadths for macrohabitat, foraging heights and foraging stations were represented on orthogonal axes, Variegated Fairy-wrens and White-winged Fairy-wrens are more alike in their use of space than either is to Superb Fairy-wrens and the greatest distance is between Superb and Variegated Fairy-wrens. In terms of survival strategies, Superb Fairy-wrens are 'opportunists', White-winged Fairy-wrens are 'coasters' and Variegated Fairy-wrens are 'stayers'.

In most species of fairy-wren (Malurus spp.), males are known to carry brightly coloured petals and display them to conspecifics. Although petal-carrying by males is often considered an inter-sexual courtship display, anecdotal observations suggest that it may also serve an intra-sexual aggressive function. In this study, we tested hypotheses for the function of petal-carrying displays in the Red-backed Fairy-wren (Malurus melanocephalus) through behavioural observations and aviary-based experiments. All petal displays observed were perpetrated by males, with 90% directed toward females and 10% toward other males. Most petal displays were performed by males in nuptial plumage during intrusions into neighbouring territories, and most displays coincided with the potential fertile period of the female to whom the display was directed. Display items consisted primarily of seeds from Gahnia sp. and flowers from Banksia sp. and Lantana sp., all of which were red or pink and similar to the red backs of nuptial males. Aviary trials found no significant difference in the responses by adult females or adult males to stimulus males with or without petals, substantiating neither a courtship role nor an aggressive role for the display. On the basis of the context of displays in the field, we conclude that the petal-carrying display in the Red-backed Fairy-wren primarily serves an inter-sexual, courtship function, though we could not rule out an intra- sexual, aggressive function.

Polygamous mating systems are expected to put sexual partners at greater risk of contracting a sexually transmissible microorganism compared with monogamy. Potentially pathogenic cloacal microorganisms such as Candida albicans, Chlamydia, coliforms and non-lactose-fermenting bacteria were studied during the non-breeding and the breeding seasons in four avian host species: two polygamous (Malurus cyaneus and Sericornis frontalis) and two monogamous (Manorina melanophrys and Neochmia temporalis). The results indicate that the highly polygamous M. cyaneus harbours more coliform and non-lactose-fermenting bacteria (which can cause disease) in its cloaca than do the polyandrous S. frontalis and the monogamous M. melanophrys. In addition, we detected higher-intensity levels of the above bacteria in avian cloacae during the non-breeding season than during the breeding season. Although not significant, trends also suggest that monogamous host species are relatively less colonised by cloacal microorganisms than are polygamous host species, whereas the latter also suffer a higher degree of multiple infection than the former.

Over the years 1990-99, a colour-banded population of Blue-breasted Fairy-wrens, Malurus pulcherrimus, was studied at Dryandra State Forest in Eucalyptus wandoo woodland. Much of this work coincided with a study (by other workers) of the same species in patches of heathland scattered through wheatland at Wyalkatchem (1993-98). At Dryandra, groups of 2-4 adults lived all year round in territories averaging 2.5 ha; clutch size was two or three eggs (mean 2.8), with more two-egg clutches laid in dry years, as at Wyalkatchem. The main difference between the two studies was in the timing of breeding. At Wyalkatchem the first clutches were laid in early August, whereas in Dryandra August is still cold, and no eggs were laid before mid-September. In wetter years laying ceased at Wyalkatchem towards the end of December but at Dryandra it continued into February. Individual nest success was low at both sites, but with a longer nesting season Dryandra groups renested more frequently and produced more fledglings (1.63 fledglings per group at Wyalkatchem, 1.93 at Dryandra). Annual survival of adults at Dryandra was c. 5% lower than for the Wyalkatchem birds, which suggests that the habitat for the species at the western edge of its distribution is sub-optimal. As at Wyalkatchem, productivity was at or above replacement level only in years of above-average rainfall. Since productivity at both sites was significantly reduced in drier years, the effect of forecast global warming causes concern for this species. Comparisons between M. pulcherrimus and the Red-winged Fairy-wren, M. elegans, illustrate how the group-living social organisation basic to all Malurus spp. can differ greatly between species as a result of differences in survival and productivity.

We review the early literature and correspondence on two cooperatively breeding Australian passerines, the Superb Fairy-wren, Malurus cyaneus, and the White-winged Chough, Corcorax melanorhamphos. We show that recognition of cooperative breeding in these species was widespread in the nineteenth century, prompting experiments and formulation of adaptive hypotheses. These early studies precede by decades the work of Alexander Skutch, who is generally credited with the ‘discovery’ of helping behaviour in Central American birds. We discuss why this early literature has been ignored.

Cloacal microparasites such as viruses, bacteria and fungi are expected to condition choice of sexual partner, as they can not only affect the expression of secondary sexual traits used in courtship, but they could be also directly transmitted to partners through copulation. We investigated the distribution of three cloacal microparasites (the bacterium Chlamydia psittaci and the yeasts Candida albicans and Kloeckeria sp.) among males and females of the sexually plumage dichromatic Malurus cyaneus and Sericornis frontalis, and the plumage monochromatic Manorina melanophrys. Males tended to be more parasitized than females within species, but the effect was stronger for the sexually dichromatic S. frontalis than for the sexually monochromatic M. melanophrys. In addition, parasitized males of the sexually dichromatic M. cyaneus had more conspicuous ear tufts (a secondary sexual trait used in courtship) than unparasitized males. The above evidence suggest that mate choice may involve a cost in terms of transmission of cloacal microparasites.

The potential influence of rainfall, habitat quality and group size on breeding success in Superb Fairy-wrens was investigated in a study of 161 nesting attempts by 62 breeding units over five breeding seasons near Armidale, New South Wales. Breeding seasons started earlier, and lasted longer, in years with higher than average rainfall, and resulted in higher seasonal breeding success. Proportionately more four-egg clutches than three-egg clutches were laid in years of higher rainfall. Breeding success was correlated with habitat quality (bramble area per territory) and Superb Fairy-wrens on territories with larger areas of brambles made more nest attempts and fledged more offspring per season than did birds with smaller areas of brambles. Brarnbles appeared to have a cumulative effect on breeding success due to better protection from nest predators. No effect of helpers on breeding success per nest attempt was evident and groups with helpers hatched no more nestlings per egg laid and fledged no more offspring per nestling hatched than did pairs. Groups and pairs did not differ significantly in the number of nesting attempts made or the number of fledglings produced per season although groups tended to re-nest sooner after successful nesting attempts than did pairs. It is suggested that the maintenance of cooperative breeding in Superb Fairy-wrens is not reliant on reproductive advantages arising from the presence of helpers at the nest but may be favoured by variation in territory quality.

Superb Maluncs cyaneus, Variegated M. lamberti and White-winged M. leucoptem Fairy-wrens co-existed at Booligal, New South Wales, where their temtories overlapped but very few interspecific interactions were observed. Temtories were established and maintained by song and less often chases between males. During nesting, the area utilised by the fairy-wrens was smaller than that established earlier. Areas that were grazed heavily were occupied less, especially by Superb Fairy- wrens. Fairy-wrens enlarged their temtories during drought. Size of a temtory correlated positively generally with the number of bushes contained within it except during drought. Temtory size correlated negatively with insect abundance for Superb and White-winged Fairy-wrens only and with the number of groups of each species except where vegetation was patchy. I suggest that temtory quality can be described best in terms of food availability, and for gleaning insectivores this may depend on the foraging area available.

Bird communities in suburban habitats are dominated by generalist species and tend to have fewer specialist species sensitive to disturbance. Superb (Malurus cyaneus) and Variegated (M. lamberti) Fairy-wrens are morphologically and ecologically similar but differ in the degree to which they occupy suburban habitats. The species often occur in sympatry in natural habitats but in suburban habitats Superb Fairy-wrens are much more common than Variegated Fairy-wrens. We compared the characteristics of the habitat of both species in natural and suburban areas to investigate whether habitat requirements differed between the species, and which may explain observed patterns of abundance. Patch-level vegetative and disturbance-related habitat characteristics of territories were compared to those of non-territories in natural and suburban habitats. In natural habitats, Superb Fairy-wrens occupied more disturbed patches than Variegated Fairy-wrens. Vegetated drainages and patches of weedy remnant vegetation were important habitats for suburban Superb Fairy-wrens, which also tolerated the presence of humans whereas Variegated Fairy-wrens were particularly sensitive to human presence. A better understanding of the factors affecting the abundance of the more sensitive native species in suburban areas, such as Variegated Fairy-wrens, may inform conservation actions to enhance suburban biodiversity.

Breeding seasons, as determined from nest record cards, for the Superb Malurus cyaneus, Variegated M. lamberti and White-winged M. leucopterus Fairy-wrens were compared within a 30-40°S latitude band and across high to low rainfall zones. All species bred mostly in spring and summer but the Superb Fairy-wrens had the most, and the White-winged Fairy-wrens the least, clearly defined breeding season. Superb Fairy-wrens in high rainfall zones bred in spring and summer but in low rainfall zones their breeding was less seasonal and followed good rains. The Variegated Fairy-wrens bred throughout most of the year in the high rainfall zone although few nests were started in autumn and winter. White-winged Fairy-wrens bred in all months of the year in low rainfall zones but there were few nests in autumn and early winter. With progression towards lower rainfall zones, species may respond opportunistically to good rains falling out of season because rainfall directly affects the amount of available food. White-winged Fairy-wrens may have a lower threshold of response to rainfall than Superb. In addition, breeding stimuli may be hierarchically arranged with increasing photoperiod being most important, followed by rainfall and food.

At Booligal, NSW, Superb Fairy-wrens Malurus cyaneus avoided orienting nest entrances towards the west and White-winged M. leucopterus avoided the south and west. Superb Fairy-wrens favoured the northern sector of bushes and White-winged the north-eastern sector to build nests. There was no relationship between nest position and the number of nests that produced fledglings. Superb Fairy-wrens built nests higher in bushes than White-winged and Variegated Fairy-wrens M. larnbeni. Chenopodium spp. bushes were preferred to others. Superb Fairy-wrens built further into a bush than Variegated and White- winged. There was generally no relationship between bush heights, volumes, distance to closest tree, placement of surrounding bushes and siting of nest. There were no interspecific effects on nest placement and successive nests were not affected by positions of earlier nests. White-winged Fairy-wrens placed their nests more centrally in territories than Superb.

In 33.5 ha of Kam forest in Smith's Brook Reserve, 841 individually colour-banded Malurus elegans, a Western Australian endemic, were studled from 1980-1986 in 24-30 territorial groups. This species is multi-brooded but less so than other Malurus due to their short breeding season; 90% of eggs were laid in October and November. Most nests (85%) were within 300 mm of the ground and more than half in accumulated litter on the forest floor, nest sites liable to be lost following fuel-reduction burning. Clutches of two and three were equally common (mean = 2.43 eggs); fertility was 94%; incubation lasted 14-15 days; nestlings hatched synchronously and fledged 11-12 days later, juveniles were independent of adult provisioning when one month old. Parasitism by cuckoos was rare and predation variable between years. Of eggs laid, 79% hatched and 52% produced fledglings. Repeat nesting was rapid and groups produced an average of 2.5 fledglings and 1.9 independent young per year. M. elegans are co-operative breeders; 82% of groups had helpers, the mean size being four adults. Both adult and juvende survival were high and the limited forest habitat was fully occupied.

Lengths of tarsus and wing, and bill dimensions, of museum specimens of Superb Malunus cyaneus, Variegated M. lamberti and White-winged Fairy-wrens M. leucopterus from all parts of their ranges (except Tasmania) were measured. Wing length of Superb Fairy-wrens increased progressively southwards: no other character measurements differed between sexes or latitudinal zones. In most zones Variegated Fairy-wren males were larger than females. White-winged Fairy-wren measurements of tarsus and bill did not vary between sexes or zones but winglength increased from north to south. No differences consistent with character displacement could be established between zones of allopatry and sympatry for any of the species. Variation in traits appears to be clinal or to have developed in isolation.

The systematic relationships of the genus Malurus were examined by comparing the radioiodine-labelled ('iSI) single copy DNA sequences of the Variegated Fairy-wren Malurus lamberti with the DNAs of thirty-seven other species of oscine birds. Malurus lamberti was found to be most closely related to other species of Malurus, and to Stipiturus, Amytornis, the acanthizine thornbills and scrubwrens, and the honeyeaters, in that order. Malurus is not closely related to the sylviine warblers, the timaliine babblers, or the muscicapine flycatchers.

Data are presented on 105 mixed-species feeding flocks of insectivorous birds on Black Mountain, ACT. About half of the sixty-nine species present participated in flocks, with an average of about four species per flock. Flocks were dominated by species that themselves form flocks and up to five such species were present at one time. Marked seasonal change occurred, with flocking activity greatest in winter and lowest in the spring breeding season. Individual species also displayed seasonal differences in participation. The genera Acanthiza and Malurus appear to behave as nucleus species, round which flocks are formed.

A completely colour-banded population of these small, sociable, multi-brooded passerines of the sub-family Malurinae was studied for more than four years at Gungahlin, Canberra, A.C.T. Their plumage, behaviour, song, breeding biology and population dynamics are discussed with particular reference to the persistence of the young-of-the-year within the family group throughout the winter, the consequent problems of dispersion and, ultimately, the frequent occurrence of more than one mature mule in the breeding group. It is suggested that this apparent polyandry enables the species to be reproductively more successful within the limits of a variable climate.

SummarySuperb Blue Wrens, Malurus cyaneus, were subjected to experimental territory infringement by means of models—prepared skins mounted in a life-like manner. Only the dominant male in the group showed aggression during winter, hut all mature members of the group (which may include more than one male) responded during nesting.When models of Malurus species, other than M. cyaneus. were presented, the initial reaction was usually negative. However, after aggressive experience with a model of its own species. M. cyaneus readily responded to models of these other dose relatives Field observations on mixed populations showed that no fighting occurred between these sympatric species.

There are few definite morphological characters which can be used to separate the flycatchers, thrushes, warblers, and babblers, and these are often grouped within the Muscicapidae, but by using a group of behavioural characters it seems possible to separate the babblers, here regarded as a family, the Timaliidae, from the others. If these characters are used the Blue Wrens of the genus Malurus would appear to be separated from the Australasian warblers of the Malurinae. Species of Malurus show social behaviour unlike that of the Muscicapidae but similar to that of the Timaliidae. The morphological characters of Malurus do not link it with any particular subfamily of the Muscicapidae, and all the characters, with the exception of the seasonal change of plumage in the male, can be found in one or other species of the Timaliidae. It is suggested that Malurus and the related genera, Todopsis, Chenorhamphus, Ctytomyias, Stipiwrlls, and Lamprolia, should be separated from the Malurinae and provisionally placed with the Timaliidae.

An examination of specimens revealed that the blue wrens, Malurus spp., emu wrens Stipiturus spp., grass-wrens, Amytornis spp., and species of the New Guinea genera Todopsis, Chenorhamphus, and Clytomyias, have the common morphological character of a gap in the interscapular zone of the spinal feather tract, this area being covered by longer feathers of the cervical and humeral tracts. This character provides a common link between genera which had been tentatively grouped together in an earlier paper, but excludes Lamprolia which had been provisionally placed with this group. Amytornis striatus and A. textilis show an extremely close resemblance to some species of babblers of the genera Garrulax, Babax, and Argya in morphology and plumage pattern, and it is considered that this is an indication of relationship of Amytornis to the Timaliidae. The behaviour of Amytornis spp., in so far as it is known, resembles that of Malurus spp. In the earlier paper it had been shown that the behaviour of Malurus spp. was like that of babblers and did not resemble that of the thrushes, flycatchers, and warblers. In view of the additional evidence it is suggested that the six genera Malurus, Stipiturus, Amytornis, Todopsis, Chenorhamphus, and Clytomyias should be regarded as an Australasian subfamily or tribe of the babblers, Timaliidae.

(1951). The Evolution of the Chestnut-shouldered Wrens (Malurus). Emu - Austral Ornithology: Vol. 51, No. 2, pp. 113-120.

(1984). Territory Quality and Group Size in the Superb Fairy-Wren Malurus Cyaneus. Emu - Austral Ornithology: Vol. 84, No. 3, pp. 178-180.

A recent survey of the birds of Barrow Island, sixty kilometres off the north-western coast of Western Australia (20°50'S, 1 15" 24'E), showed a small avifauna with few land-birds (Sedgwick 1978). During tenure of the WAPET 1979 Barrow Island Research Grant, we compared the diets of the three most common birds on the island: Singing Honeyeater Meliphaga virescens, Spinifexbird Eremiornis carteri and Black-and-white Fairy-wren Malurus 1. leucopterus. These species were widespread among the spinifex and its emergent shrubs and, apart from a few cuckoos and pipits, were the only birds that exploit insects on the ground and round vegetation. Flying insects were taken by Welcome Swallows Hirundo neoxena, Tree Martins Petrochelidon nigricans and White-breasted Woodswallows Artamus leucorhynchus, which were not studied.