Neochmia Phaeton Research Articles

Orange pigment variety in Black-bellied Crimson Finch Neochmia phaeton phaeton from West Kimberley, Australia

During standardised bird surveys in September 2021 in the West Kimberly, two independent observations of an orange pigment variety in a male Black-bellied Crimson Finch Neochmia phaeton phaeton were recorded. This is the first documented observation of a wild Black-bellied Crimson Finch with this coloration.

Breeding biology of Crimson Finches (Neochmia phaeton) in the eastern Kimberley, Western Australia

ABSTRACTMany species show pronounced differences in life-history traits, from the individual level to divergences between distinct populations. Understanding the variation in these traits provides not only an insight into individual fitness but also essential information for the management of wild populations. Despite their popularity in aviculture and importance for captive research, our knowledge of many Estrildid finches in the wild is limited. Here we detail the breeding behaviour of 12 discrete colonies of Crimson Finch (Neochmia phaeton) in the east Kimberley region of Western Australia over two breeding seasons, and contrast our findings with studies on populations occupying different habitats. We found that many aspects of Crimson Finch breeding biology were consistent across site and studies. However, in our populations, adult survival was lower and group sizes were larger than has been reported elsewhere. We also examined age and sex differences in nestling care and found weak support for age or sex differences in feeding rates. We briefly discuss these findings in relation to theories of colony formation. These findings may help explain the evolution of colonial breeding in this species, as well as having implications for long-term ecosystem management.

Male-male pair bonding, nesting and egg incubation in a wild passerine

Examples of nesting behavior between pair-bonded males are exceedingly rare among songbirds. We observed a male same-sex pair bond that resulted in the partial development of one egg while monitoring the breeding activity of a population of wild Crimson Finches (Neochima phaeton) over four breeding seasons. This male–male pair built four nests and incubated two clutches, each with a single egg of unknown origin, with at least one developing partially before failing. This same-sex behavior is unusual among passerines and its origin and evolutionary significance remain poorly understood.

Wings of tropical finches: interspecific differences in shape are consistent with levels of mobility, but moult and feather fault patterns are more complex

ABSTRACTBirds’ wings reflect their life histories, suggesting evolutionary selection for wing shapes and moult strategies. Compared to sedentary species, long-distance migrants have narrower wings (for fast, efficient flight); they have fewer feather faults and avoid moulting flight feathers during migration (to optimise flight surface performance). It is unclear whether these patterns apply to species that fly short-intermediate distances, like tropical nomads. We compared wing shape, feather faulting, and flight-feather moult across five finch species from northern Australia with varying mobility: Pictorella Mannikins (Heteromunia pectoralis) and Gouldian Finches (Erythrura gouldiae) are highly mobile, nomadic at regional scales; Long-tailed Finches (Poephila acuticauda) and Double-barred Finches (Taeniopygia bichenovii) are sedentary with local nomadism; Crimson Finches (Neochmia phaeton) are sedentary. More mobile species had narrower wings and higher wing loading than relatively sedentary species, and less feather faulting. Variation in moult strategies was complex, but mobile species carried out moult fast, in a short time window, and moulted a single feather at a time. Unexpectedly, Gouldian Finch wings were more suited for fast efficient flight than Pictorella Mannikin wings, and yet they had more feather faulting. Differences in mobility may be a key dimension of niche separation that allows these species to co-exist.

Predictors of aggressive response towards simulated intruders depend on context and sex in Crimson Finches (Neochmia phaeton)

Quantifying differences in aggressive behaviour across contexts can be useful in developing an understanding of life histories and breeding systems, as well as the relative costs and benefits of such behaviour. We investigated whether age, relative body size and colouration, sex, and breeding stage influenced levels of aggressive behaviour in two contexts, towards conspecific and heterospecific intruders (mounts) around active nests of group living Crimson Finches (Neochmia phaeton). We found that when responding to a conspecific mount, relative body size, and age were important in predicting the aggressive response of males toward a conspecific, with older males and those close in size to their opponent showing a higher aggressive response. On the other hand, factors relating to female aggression were not as clear. In contrast, response to a heterospecific mount was unrelated to age, colour or size in either sex. Additionally, although birds were equally aggressive to conspecific and heterospecific mount types, we found no evidence that individuals are consistent in their level of aggression across these contexts. This suggests that aggressive behaviour in Crimson Finches is at least partially plastic and that individuals may be capable of assessing and responding to situations independently.

Grassfinch decline and local extinction of the Crimson Finch Neochmia phaeton in the Fitzroy River Basin, Queensland

Many granivorous birds of northern Australia, including several species of grassfinches (Estrildidae), have suffered substantial range contractions in the last 50–100 years, apparently as a result of changes in cattle grazing and fire-management regimes. The Crimson Finch Neochmia phaeton was once widespread in woodlands and savannas of north-eastern Australia, including the extensive Fitzroy River Basin, where it was recorded in all the major subcatchments until the middle of last century. However, surveys in 2006–2008 show that it is now confined to a relatively small area in the north-east of the Basin. A tall river grass, Chionachne Chionachne cyathopoda , is an important component—for food and cover—of its habitat. Complex braiding of river channels, as at the confluence of rivers, is typical of the area where the Finches have persisted, possibly because it increases the availability of water and food, and reduces pressure from cattle grazing during the wet season. A recent local loss of the species was noted in one area where landholders used riparian fencing to maintain greater grazing intensity throughout the year, leading to suppression of Chionachne seeding. Thus, although generally favourable for conservation management, riparian fencing can also be used detrimentally. The loss of one local subpopulation of Finches following changed management practices demonstrates that cattle grazing alone, in the absence of changed fire management, has the capacity to alter habitat suitability for granivorous species.

The influence of nest-site choice and predator sensory cues on nesting success in the Crimson Finch (Neochmia phaeton)

The attributes of a nest-site that a bird selects may be influenced by the potential predator species present, as different types of predator use different foraging strategies and sensory cues to locate nests. However, in many studies of avian nesting, the identity of the main nest predators and their foraging strategies are not known, limiting our interpretation and understanding of how choice of nest-site and nesting success might be linked. We investigated nest-site choice, nest survival and the nest predators in a population of Crimson Finch (Neochmia phaeton) in tropical Australia. Crimson Finches preferred to nest among foliage of the crowns of Pandanus on stems with aquatic barriers, and near old nests of conspecifics. However, none of these or any other attributes of nest-sites that we recorded significantly affected nest survival. Moreover, neither visual nor olfactory cues influenced nesting success in field experiments with quail eggs. Similar rates of predation of natural and experimental nests, coupled with similar rates of daily predation of eggs and nestlings suggest that predators were not using nest-attendance behaviour of the adult Finches as a cue to find active nests. Identified nest predators were reptiles; our study suggests that Crimson Finches may not be able to choose nest-sites that reduce the ability of these olfactory-driven predators.

The role of pigment based plumage traits in resolving conflicts

The role of melanin ‘badges of status’, in male–male competition has been well‐studied, in contrast, carotenoid based plumage has largely been examined in the context of female mate choice. Recent work has shown that carotenoid signals can also function in male–male competition, although the functions of the two types of signals is currently unclear. Here, we examine the relationships between colouration, dominance and aggression in the crimson finch Neochmia phaeton, a species where males have both conspicuous red carotenoid plumage and a black melanin patch. We examined the importance of carotenoid and melanin based signals in three contexts: 1) among free‐living birds interacting at a feeding station: we found that neither colour signal influenced the outcome of interactions; 2) in staged dyadic contest in captivity: we found that coloration from carotenoid pigments was positively related to the probability of winning a contest, while the size of the melanin plumage patch was not related to winning; and 3) in staged dyadic contests where male plumage colour had been masked: we found that the number of interactions required to determine dominance increased. While the underlying natural plumage colour was still important in these contests, birds with more intense carotenoid colouration were now more likely to lose. These results confirm carotenoid‐based signalling in male–male contests. However this signal is used in conjunction with other factors such as self‐assessment and body condition. Contrary to traditional expectations, the black melanin patch was not found to be important in this context.

Nesting Success in Crimson Finches: Chance or Choice?

AbstractIn avian systems, nest predation is one of the most significant influences on reproductive success. Selection for mechanisms and behaviours to minimise predation rates should be favoured. To avoid predation, breeding birds can often deter predators through active nest defence or by modifying behaviours around the nest (e.g. reducing feeding rates and vocalisations). Birds might also benefit from concealing nests or placing them in inaccessible locations. The relative importance of these strategies (behaviour vs. site selection) can be difficult to disentangle and may differ according to life history. Tropical birds are thought to experience higher rates of predation than temperate birds and invest less energy in nest defence. We monitored a population of crimson finches (Neochmia phaeton), in the Australian tropics, over two breeding seasons. We found no relationship between adult nest defence behaviour (towards a model reptile predator) and the likelihood of nest success. However, nest success was strongly related to the visibility of the nest and the structure of the vegetation. We found no evidence that adult nest building decisions were influenced by predation risk; individuals that re‐nested after a predation event did not build their nest in a more concealed location. Therefore, predator avoidance, and hence nest success, appears to be largely due to chance rather than due to the behaviour of the birds or their choice of nesting sites. To escape high predation pressures, multiple nesting attempts both within and between seasons may be necessary to increase reproductive success. Alternatively, birds may be limited in their nest‐site options; that is, high‐quality individuals dominate quality nest sites.

Invasive toads shift predator-prey densities in animal communities by removing top predators.

Although invasive species can have substantial impacts on animal communities, cases of invasive species facilitating native species by removing their predators have rarely been demonstrated across vertebrate trophic linkages. The predictable spread of the invasive cane toad (Rhinella marina), however, offered a unique opportunity to quantify cascading effects. In northern Australia, three species of predatory monitor lizards suffered severe population declines due to toad-induced lethal toxic ingestion (yellow-spotted monitor (Varanus panoptes), Mertens' water monitor (V. mertensi), Mitchell's water monitor (V. mitchelli). We, thus, predicted subsequent increases in the abundance and recruitment of prey species due to the reduction of those predators. Toad-induced population-level declines in the water monitor species approached 50% over a five-year period spanning the toad invasion, apparently causing fledging success of the Crimson Finch (Neochmia.phaeton) to increase from 55% to 81%. The consensus of our original and published long-term data is that invasive cane toads are causing predators to lose a foothold on top-down regulation of their prey, triggering shifts in the relative densities of predator and prey in the Australian tropical savannah ecosystem.

Body Condition Indices Predict Reproductive Success but Not Survival in a Sedentary, Tropical Bird.

Body condition may predict individual fitness because those in better condition have more resources to allocate towards improving their fitness. However, the hypothesis that condition indices are meaningful proxies for fitness has been questioned. Here, we ask if intraspecific variation in condition indices predicts annual reproductive success and survival. We monitored a population of Neochmia phaeton (crimson finch), a sedentary, tropical passerine, for reproductive success and survival over four breeding seasons, and sampled them for commonly used condition indices: mass adjusted for body size, muscle and fat scores, packed cell volume, hemoglobin concentration, total plasma protein, and heterophil to lymphocyte ratio. Our study population is well suited for this research because individuals forage in common areas and do not hold territories such that variation in condition between individuals is not confounded by differences in habitat quality. Furthermore, we controlled for factors that are known to impact condition indices in our study population (e.g., breeding stage) such that we assessed individual condition relative to others in the same context. Condition indices that reflect energy reserves predicted both the probability of an individual fledging young and the number of young produced that survived to independence, but only during some years. Those that were relatively heavy for their body size produced about three times more independent young compared to light individuals. That energy reserves are a meaningful predictor of reproductive success in a sedentary passerine supports the idea that energy reserves are at least sometimes predictors of fitness. However, hematological indices failed to predict reproductive success and none of the indices predicted survival. Therefore, some but not all condition indices may be informative, but because we found that most indices did not predict any component of fitness, we question the ubiquitous interpretation of condition indices as surrogates for individual quality and fitness.

Body-condition indices are repeatable across short, but not long, time periods in crimson finches Neochmia phaeton.

Abstract It is common in evolutionary ecology to interpret body-condition indices as indicators of individual quality, but this hypothesized relationship has been questioned and remains poorly validated. Here, we test one of the fundamental predictions of this condition-quality hypothesis, that relative-condition indices are repeatable within individuals, that is, that the index score of an individual relative to others is consistent over time. We sampled crimson finches (Neochmia phaeton) for seven commonly used condition indices and tested whether individual condition relative to conspecifics in the same context (e.g., breeding stage) was repeatable. We calculated the relative indices' repeatability across several temporal scales, from short (within breeding season) to long (more than 2 yr) time periods, as well as without consideration of timescale. Most relative-condition indices were repeatable when sampled without consideration of timescale, all were repeatable within a short time period, and none were repeatable over the longest time period. This provides only partial support for the condition-quality hypothesis, because although relative-condition indices were generally repeatable, this was primarily attributed to short-term, instead of long-term, repeatability. Condition indices may be meaningful indicators of short-term survival or fitness potential, but our findings are inconsistent with the idea that condition indices are indicators of inherent individual quality.

Variation in body condition indices of crimson finches by sex, breeding stage, age, time of day, and year.

Body condition indices are increasingly applied in conservation to assess habitat quality, identify stressed populations before they decline, determine effects of disturbances, and understand mechanisms of declines. To employ condition indices in this manner, we need first to understand their baseline variability and sources of variation. Here, we used crimson finches (Neochmia phaeton), a tropical passerine, to describe the variation in seven commonly used condition indices by sex, age, breeding stage, time of day, and year. We found that packed cell volume, haemoglobin, total plasma protein, and scaled mass were all significantly affected by an interaction between sex and breeding stage. Furcular fat varied by sex and breeding stage and also trended by year, scaled mass showed a positive trend with age and varied by time of day, and haemoglobin additionally varied by year. Pectoral muscle scores varied and heterophil to lymphocyte ratio trended only by year. Year effects might reflect a response to annual variation in environmental conditions; therefore, those indices showing year effects may be especially worthy of further investigation of their potential for conservation applications. Pectoral muscle scores and heterophil to lymphocyte ratio may be particularly useful due to the lack of influence of other variables on them. For the other indices, the large variation that can be attributed to individual covariates, such as sex and breeding stage, suggests that one should not interpret the physiological condition of an individual as measured by these indices from their absolute value. Instead, the condition of an individual should be interpreted relative to conspecifics by sex, breeding stage, and possibly age.

EFFECT OF A MAJOR FLOOD ON BREEDING AND HABITAT OF THE CRIMSON FINCH (NEOCHMIA PHAETON): A RIPARIAN SPECIALIST

ABSTRACTRiparian specialists, such as the Crimson Finch (Estrildidae: Neochmia phaeton), are vulnerable to declines in habitat quality, including alterations of flow regime associated with dam construction. Crimson Finches persisted and bred in substantial numbers following two large floods in the Isaac–Connors catchment in early 2008. Major flooding was not detrimental to nesting and breeding success, although the immediate post‐flood period was identified as a bottleneck in the availability of riparian grass seed. Crimson Finches nested at 16 m or more above the normal river level (compared with an average of 2–3 m elsewhere in Northern Australia); indicating that they have adapted to the extreme flood peaks in the Fitzroy River basin. The tall river‐associated grass Chionachne cyathopoda was a key habitat plant, retaining seed well into the dry season when most other grasses are expended. It also provided abundant seeds following floods, coinciding with peaks in abundance of dependent young finches. The adaptations of both Crimson Finches and Chionachne suggest that increased flooding, predicted by climate change, is unlikely to be a problem. In contrast, a proposed dam on the Connors River may be a threat. River regulation that reduces peaks of major floods may favour introduced riparian grasses over flood adapted native grasses such as Chionachne. Any change in the quantity of this species could be detrimental to persistence of Crimson Finches. Environmental managers should carefully consider the ecology of Chionachne when making decisions about river flows. Copyright © 2013 John Wiley & Sons, Ltd.

Breeding biology and life-history traits of an Australasian tropical granivore, the Crimson Finch (Neochmia phaeton)

The evolutionary basis of the latitudinal gradient in clutch-size is a major, unresolved question in life-history theory, the resolution of which is hampered by the lack of proportionate study of southern passerines. Here, we present detailed data on breeding biology and life history for an Australasian tropical granivore, the Crimson Finch (Neochmia phaeton), emphasising aspects of their life history that are atypical of southern passerines. We collected data over three breeding seasons at Mornington Wildlife Sanctuary in north-western Australia. Apparent annual survival of adults was high, at 70–96%. Crimson Finches were multi-brooded and laid 5.08 ± 0.07 eggs per clutch. The rate of nest predation was high, with 59.7% of clutches lost to predation. Thus, Crimson Finch life history contradicts the leading explanation of the clutch-size gradient—that higher rates of nest predation and higher adult survival in southern species select for smaller clutch-sizes. Our findings are more consistent with other explanations of the clutch-size gradient, specifically those involving post-fledging parental care, diet, seasonality and phylogeny. Exploring life histories that differ from the norm may be particularly helpful in understanding latitudinal differences in these strategies.

Morphological and dietary differences between common and uncommon subspecies of Crimson Finch, Neochmia phaeton, and Star Finch, Neochmia ruficauda, in northern Australia

Bill measurements and crop contents were collected from the uncommon subspecies of Crimson and Star Finches, Neochmia phaeton evangelinae and N. ruficauda clarescens, at two sites on Cape York Peninsula. Bill measurements and crop analyses were also taken from the widespread and common N. p. phaeton and N. r. subclarescens in Kununurra, Western Australia. Bill depth and bill width differed significantly between species and among subspecies. The common subspecies possessed wider bills and consumed seeds with a larger mean diameter. The range of seed diameters consumed was also related to bill width, but this relationship was apparent only during the dry season. The seeds found and consumed by adult N. r. clarescens during the dry season were also significantly smaller than those taken by immatures. Management implications are discussed.

Comments on the Subspecies of Australian Native and Introduced Finches

Finches of the families Passeridae (Estrildinae; Passerinae: Ploceini, Passerini) and Fringillidae (Fringillinae: Fringillini, Carduelini; Emberizinae) are represented in Australia and its island dependencies by 18 native and 12 introduced species. Subspecies recognised in recent years have been largely confirmed; changes proposed here are the merger of Neochmia phaeton albiventer with N. p. evangelinae; N. p. iredalei with N. p. phaeton; and Lonchura castaneothorar assimilis with L. c. custaneothorax. The subspecific status of Poephila cincta nigrotecta and P. acuticauda hecki is supported. Seven species are monotypic and three polytypic species have only one Australian subspecies. Introduced species are mainly either the result of acclirnatisation societies or presumably of self-colonisation from New Zealand; the latter have been recorded only from island territories and are assumed to belong to the subspecies found in New Zealand. Subspecific assignment has not been made for Passer rnontanus on Christmas Island.

Phylogeny and Systematics of Estrildine Finches and Their Relationships to Other Seed-eating Passerines

SummaryChristidis, L. (1987). Phylogeny and systematics of estrildine finches and their relationships to other seed-eating passerines. Emu 87, 119–123.A cladistic analysis of chromosomal and electrophoretic data provided the basis for a phylogeny and revision of estrildine finches. The results indicate that estrildines are best treated as a subfamily, Estrildinae, within the Passeridae. The Estrildinae themselves comprise three natural tribal assemblages: Poephilini (grassfinches), Lonchurini (mannikins) and Estrildini (waxbills). Of these, the Lonchurini appear to be the most recently evolved. The Red-browed Finch Aegintha temporalis and Plum-headed Finch Aidemosyne modesta are each other's closest relatives and, together with the Star Finch Neochima ruficauda and Crimson Finch N. phaeton, constitute a single genus. The currently recognised genera, Poephila, Emblema and Lonchura are split into several smaller genera.

Avian Hybridization and Allopatry in the Region of the Einasleigh Uplands and Burdekin-Lynd Divide, North-Eastern Queensland

The Einasleigh Uplands and Burdekin-Lynd Divide comprise an elevated section of the Great Dividing Range in north- eastern Queensland. About twenty avian species of eucalypt forest, woodland and grassland habitats have range gaps, hybrid zones or stepped size-clines in the region of these uplands. Species and species-pairs with a discontinuous or partly discontinuous range include the Lemon-bellied Flycatcher Microeca flavigaster, Restless Flycatcher Myiagra inquieta, White-gaped Honeyeater Lichenostomus unicolor, Yellow Honeyeater Lichenostomus flavus, Fuscous/Yellow-tinted Honeyeaters Lichenostomus fuscus/flavescens, Bar-breasted Honeyeater Ramsayornis fasciatus, Crimson Finch Neochmia phaeton, Star Finch Neochmia ruficauda and Chestnut-breasted Mannikin Lonchura castaneothorax. Those with a hybrid zone are the Squatter Pigeon Petrophassa (Geophaps) scripta, Pale-headed Rosella Platycercus adscitus, Brown Treecreeper Climacteris picumnus, Black-chinned Honeyeater Melithreptus gularis, Striated Pardalote Pardalotus striatus and Black-throated Finch Poephila cincta. Stepped size-clines or sharp morphological changes occur in the Brown Goshawk Accipiter fasciatus, Barking Owl Ninox connivens, Masked Owl Tyto novaehollandiae, Tawny Frogmouth Podargus strigoides and Laughing Kookaburra Dacelo gigas. Though some of the hybrid zones and steps might have been produced by nearby geographical barriers consisting of low rainfall salients, the upland-divide is an active barrier at present. A cooler climate in the upland-divide now, and presumably in past times, appears to be the cause of present and past range gaps because relevant habitats are continuous throughout north-eastern Queensland. Two taxa, Accipiter fasciatus and Melithreptus gularis, might each be composed of two species; because the small (didimus) and large (fasciatus) forms of A. fasciatus possibly both occur in tropical Australia throughout the year rather than only in winter when the large form is presumed to be a southern migrant; and the evidence for hybridization between the altitudinal vicariant forms gularis and laetior is equivocal. Most geographical barriers between isolated avian populations on the Australian mainland to consist of arid or low-rainfall belts extending to the coast but other cold upland sections of the Great Dividing Range besides the Einasleigh Uplands and Burdekin-Lynd have operated as barriers. These include the McPherson Range and Blue Mountains-Snowy Mountains chain.

The Taxonomic Position of the Crimson Finch and the Red-browed Finch

A study of spotted plumage patterns in the Estrildidae reveals a limited potential variation and the parallel evolution of similar patterns in different areas. The Crimson Finch, Red-browed Finch, Painted Finch, and Firetails all show plumage colorations and patterns similar to those of African Waxbills, but revealing varying degrees of likeness. It is suggested that these are the results of convergence arising from the parallel evolution of patterns in birds having a common ancestry. Examining the group of behavioural characters used to define some waxbill genera, it was found that the Crimson Finch resembled the atypical members of the waxbill genus Lagonosticta in some characters, and shared other characters with different The Red-browed Finch shared most of the characters of the African genus Estrilda with only minor differences. It is suggested that, since behavioural characters are inherited in similar fashion to plumage characters, this similarity In behaviour could be due to convergence. Since the difference between the Crimson Finch and Red-brewed Finch is as great as that between different waxbill genera, it is suggested that they should be regarded as members of separate monotypic genera.