Auswahl der wissenschaftlichen Literatur zum Thema „Honeyeaters“

This study aimed to investigate the extent of habitat overlap and competition between helmeted honeyeaters and bell miners at Yellingbo State Nature Reserve by comparing the structural attributes of occupied habitat, the spatial distribution of suitable and occupied habitat, and the reoccupation of former habitat by the helmeted honeyeater following bell miner removal. The results suggest that little niche overlap occurs between the two honeyeaters, at least within the range of structural attributes measured in the study, and that competition appears to be for space rather than any other limiting resource. It is concluded that, in the short term, the best way to minimise the conflict between the two honeyeaters and favour the expansion of helmeted honeyeaters is to remove bell miners from adjacent habitat.

Allozyme variation at 18 presumptive loci among 15 species of Australo-Papuan passerines was used to clarify the affinities of the aberrant genera Toxorhamphus, Oedistoma, Timeliopsis and Epthianura, all conventionally associated with honeyeaters (Meliphagidae). Both distance-based and discrete-state phylogenetic analyses were performed on the data. The analyses corroborated results from DNA-DNA hybridisation studies that Toxorhamphus and Oedistoma are not honeyeaters, but in fact are related to the berrypeckers and flowerpeckers Melanocharis and Dicaeum. Oedistoma iliolophus was found to be more closely allied to Melanocharis than to Toxorhamphus. This result is consistent with generic separation of O. iliolophus from Toxorhamphus, contrary to groupings interpreted from DNA-DNA hybridisation data. Timeliopsis was identified as a typical honeyeater despite the atypical form of its tongue. Epthianura was also aligned with the honeyeaters but, contrary to analysis by DNA-DNA hybridisation, only as a sister-group of the core honeyeater assemblage.

Field metabolic rate (FMR) and water influx of New Holland honeyeaters (Phylidonyris novaehollandiae), eastern spinebills (Acanthorhynchus tenuirostris) and a crescent honeyeater (P. pyrrhoptera) were measured by the doubly labelled water technique. New Holland honeyeaters had just finished breeding and were beginning their summer moult. They ranged in mass from 15.4 to 21.0 g (mean = 17.3 g, n = 12) and had FMRs averaging 8.8 mt CO2 g(-1) h(-1) or 77.6 kJ day(-1), which was 2.8 times their measured basal metabolic rate (BMR). Their water influx rate averaged 10.7 mL day(-1). Eastern spinebills were still feeding young and had yet to begin moulting. They ranged in mass from 8.0 to 10.7 g (mean = 9.7 g, n = 6), had FMRs averaging 10.9 mL CO2 g(-1) h(-1) or 52.9 kJ day(-1) (2.5 times their measured BMR), and had an average water influx rate of 8.7 mL day(-1). FMR and water influx of a single 14.6-g crescent honeyeater, which was in late primary moult, were 75.9 kJ day(-1) (2.7 times measured BMR) and 12.5 mL day(-1). The FMR of New Holland honeyeaters varied inversely with mean standard operative temperature (T-es) calculated for values of T-es below 20 degrees C as follows: FMR (kJ day(-1)) = 134 - 5.47 T-es (n = 12, r(2) = 0.52). Honeyeater FMRs were much lower than would be predicted allometrically for hummingbirds of the same mass, reflecting the honeyeaters' low-cost foraging tactic of consuming nectar while perched.

This is the first Australian study to apply logistical modelling techniques to describe the breeding habitat selection of a widely dispersed, highly mobile, threatened bird species. Landscape and microhabitat structural attributes of breeding habitat occupied by the endangered Regent Honeyeater Anthochaera phrygia in the Bundarra-Barraba region of northern NSW were compared to those of unoccupied habitat using logistic regression modelling. Models containing landscape scale variables were best at explaining Regent Honeyeater presence. Regent Honeyeater occupation was negatively associated with the amount of woodland cover surrounding a site (1 km and 2 km radius) and distance to patch edge, and was positively associated with site connectivity and linear remnants. Linear, well-connected woodland patches surrounded by cleared grazing land are typical of the remnant native vegetation occupied by Regent Honeyeaters in the Bundarra-Barraba region. The landscape models developed here can be used to identify potential new sites for protection and rehabilitation, and to assess the suitability of unsurveyed or unoccupied sites for the release of captively bred Regent Honeyeaters, which is identified as one of the priority recovery action for the species.

One of the suggested reasons for the decline of the endangered regent honeyeater, Xanthomyza phrygia, is a decrease in foraging efficiency and increase in competition for resources due to the loss, fragmentation and degradation of woodlands and other habitats in south-eastern Australia. This study investigated the general behaviour of regent honeyeaters over 26 months during breeding and non-breeding seasons at three distinct locations in northern New South Wales. At the three locations, regent honeyeaters spent, on average, 43–52% of total time foraging, 22–40% resting, 6–10% flying, and 1.8–2.9% involved in aggression. In the Bundarra–Barraba region, regent honeyeaters spent 24% of total time breeding. In 1994 in the Warrumbungle National Park, birds that fed primarily on nectar spent more time in aggressive acts than birds that fed mostly on lerp. In 1995 in the Bundarra–Barraba region, nectar-feeding birds spent significantly less time foraging and more time in aggressive acts than lerp-feeding birds. In 1994, regent honeyeaters at Howes Valley spent less time foraging and in aggression and greater time resting in the afternoon than at other times of the day. In 1996 in the Bundarra–Barraba region, birds spent the greatest amount of time in aggressive acts and the least amount of time resting in the morning compared with other times of the day. Non-breeding regent honeyeaters in the Bundarra–Barraba region spent more time foraging, less time resting and less time in aggression in 1995 than in 1996. Non-breeding birds, on average, chased other birds 12.5 times per hour compared with an average of 20 times for breeding birds. Regent honeyeaters displayed a behavioural repertoire and proportion of time in different activities that is typical of other honeyeaters. Overall, this study showed that regent honeyeaters are not consistently or frequently suffering from a lack of, or problems with access to, food.

Abstract We reassessed whether two parapatric non-sister Australian honeyeater species (Aves: Meliphagidae), varied and mangrove honeyeaters (Gavicalis versicolor and G. fasciogularis, respectively), that diverged from a common ancestor c. 2.5 Mya intergrade in the Townsville area of north-eastern Queensland. Consistent with a previous specimen-based study, by using genomics methods we show one-way gene flow for autosomal but not Z-linked markers from varied into mangrove honeyeaters. Introgression barely extends south of the area of parapatry in and around the city of Townsville. While demonstrating the long-term porosity of species boundaries over several million years, our data also suggest a clear role of sex chromosomes in maintaining reproductive isolation.

We revisited a location to study previously individually marked Tagula Honeyeaters Microptilotis vicina in 2019, 3 years after the original 2016 study on Junet Island, Louisiade Archipelago, Papua New Guinea. Re-encountered Tagula Honeyeaters indicated sedentary behaviour across years and an average annual adult survival rate of ≥0.75. We made the first observations of building and laying at two nests, and recorded nesting habits in the species. Tagula Honeyeaters showed the general trend in the honeyeater family of only the female building the nest and incubating. Nests were similar to those previously observed and to those of related species. Clutch-size in both nests was two and laying was on consecutive days. Eggs were white to off-white, with a ring of liver-brown spots and markings around the larger end. Incubation began on the day that the second egg was laid and lasted 14 days in both nests. Males visited the nest area only after the eggs hatched. At one nest, the nestling period was suspected to be 12 days. These limited observations of the only endemic island representative in Microptilotis indicate that, like plumage characters, breeding parameters remain similar within the genus.

Six juvenile regent honeyeaters, Xanthomyza phrygia, from a captive population held at Taronga Zoo, Sydney, were tested for their orientation in the early morning between April and July 1998. Testing was performed outdoors in Emlen orientation cages, which were covered with opaque lids. All study birds oriented in a north-easterly direction between April and late May (Stage 1). During June and July (Stage 2) no uniform directional preferences were shown. The results obtained for regent honeyeaters during the April/May period suggest that there is some genetic control of seasonal movements and that the birds use a non-visual compass mechanism, as in some migratory Australian birds. The interpretation of our results remains tentative due to the lack of knowledge of regent honeyeater movements in the wild.

The results of phylogenetic analysis of two molecular datasets sampling all three endemic New Zealand ‘honeyeaters’ (Prosthemadera novaeseelandiae, Anthornis melanura and Notiomystis cincta) are reported. The undisputed relatedness of the first two species to other honeyeaters (Meliphagidae), and a close relationship between them, are demonstrated. However, our results confirm that Notiomystis is not a honeyeater, but is instead most closely related to the Callaeidae (New Zealand wattlebirds) represented by Philesturnus carunculatus in our study. An estimated divergence time for Notiomystis and Philesturnus of 33.8 mya (Oligocene) suggests a very long evolutionary history of this clade in New Zealand. As a taxonomic interpretation of these data we place Notiomystis in a new family of its own which takes the name Notiomystidae. We expect this new phylogenetic and taxonomic information to assist policy decisions for the conservation of this rare bird.

We define territorial behaviour as aggressive behaviour that occurs repeatedly in about the same location with associated submissive behaviour on the part of the individuals or groups to which the aggression is directed. Of a worldwide total of about 170 honeyeater species (Meliphagidae), 36 have been described as being territorial and we consider that 28 of these have been shown to satisfy our definition of territoriality. We discuss the consequences of territorial behaviour and the determination of the boundaries and areas of territories. We also review the available information regarding territorial behaviour exhibited by the New Holland honeyeater (Phylidonyris novaehollandiae), the most studied of all honeyeater species. We recommend that future descriptions of territorial behaviour attempt to determine the intensity of the behaviour, sharpness of the territory boundary, degree of exclusive use of the relevant resource, and the extent to which areas separate from the territory are used by the territory owner or owners. For territoriality to become a useful concept for honeyeaters, behaviour that leads to the label of 'territorial' must be fully documented.

This thesis examines the form and function of the kidney of corvid meliphagid honeyeaters. The kidneys of seven species inhabiting the wet zone environment were compared with the kidneys of seven species inhabiting the arid zone environment. Gross anatomy and vasculature of the kidney were similar to other avian species. Histological structure was similar between arid .and wet zone species, as determined by light histology as well as by transmission and scanning electron microscopy. It differed from that found in muscicapid passerines, in the arrangement of tubules within the medulla and in the ultrastructural morphology of the loop of Henle. A quantitative analysis using stereology showed that most arid zone species: had a proportionately higher volume of renal medulla, a higher proportion of looped nephrons, and longer loops of Henle than did wet zone species. Wet zone species had a higher percentage volume of collecting ducts and arid zone honeyeaters had a higher percentage volume of medullary capillaries. Qualitatively there was no difference in the nephron components between species. The histological structure of the lower gastrointestinal tract was similar in both arid and wet zone honeyeaters. Physiological experiments were conducted on two arid zone species: Phylidonyris albifrons and Meliphaga penicillata and three wet zone species: Phylidonyris novaehollandiae, Anthochaera lunulata and Anthochaera carunculata. When fed on artificial nectar diets ranging from more dilute (200mOsm) to within the osmolality range of nectar (600 - 1300 mOsm), the arid zone honeyeaters consumed more food, excreted more urine and gained more body mass than did the wet zone honeyeaters. On these diets all honeyeaters excreted a hyposmotic urine. There was no difference between species in: the concentration of urinary and plasma sodium and potassium ions, plasma osmolality, haematocrit and the concentration of uric acid. On diets more concentrated than nectar (2000 - >2000mOsm), all birds lost a significant amount of body mass. Arid zone species excreted a significantly higher concentration of sodium in the urine and wet zone species increased the level of plasma osmolality more so than did the arid zone species. Arid zone species also had a higher urine to plasma osmolality ratio than did wet zone species. These results suggest that arid zone honeyeaters are better able to concentrate urine, and if the birds' habitat is altered, certain arid zone species may adapt successfully to a wet zone environment, however, wet zone species may find it difficult to adapt to an arid zone environment.

Densities and behaviour of Noisy Friarbirds Philemon corniculatus and Red Wattlebirds Anthochaera carunculata were measured during 1992 and 1993 at six sites along an east-west transect through central New South Wales from the Central Coast through to the Central Western Slopes, and at Goobang National Park from 1993 to 1996. Both P. corniculatus and A. carunculata were found to be mostly canopy foragers with occasional forays into the shrub layer when food resources became available there. Flower-probing and foliage gleaning comprised the bulk of foraging behaviour. Most of the food resources used by these honeyeaters were seasonally unreliable and unpredictable, so that they needed to shift between foods and track them over hundreds of kilometres. A strong relationship was found between the densities of honeyeaters and the density of flowering trees at both regional and local scales. Sites on the western slopes were more important for nectar during winter and spring, while sites on the tablelands provided a greater diversity of foods over all seasons. When foraging at foliage, both honeyeaters were found to preferentially select Eucalyptus punctata. These two honeyeaters are very mobile and appear to cope within the fragmented landscape. Their ecological role as plant pollinators, seed dispersers and insect population limiters may have increased proportionally due to habitat fragmentation compared with less mobile species with similar ecological roles. Hence they may also have become more important in maintaining habitat patch quality
Doctor of Philosophy (PhD)

Densities and behaviour of Noisy Friarbirds Philemon corniculatus and Red Wattlebirds Anthochaera carunculata were measured during 1992 and 1993 at six sites along an east-west transect through central New South Wales from the Central Coast through to the Central Western Slopes, and at Goobang National Park from 1993 to 1996. Both P. corniculatus and A. carunculata were found to be mostly canopy foragers with occasional forays into the shrub layer when food resources became available there. Flower-probing and foliage gleaning comprised the bulk of foraging behaviour. Most of the food resources used by these honeyeaters were seasonally unreliable and unpredictable, so that they needed to shift between foods and track them over hundreds of kilometres. A strong relationship was found between the densities of honeyeaters and the density of flowering trees at both regional and local scales. Sites on the western slopes were more important for nectar during winter and spring, while sites on the tablelands provided a greater diversity of foods over all seasons. When foraging at foliage, both honeyeaters were found to preferentially select Eucalyptus punctata. These two honeyeaters are very mobile and appear to cope within the fragmented landscape. Their ecological role as plant pollinators, seed dispersers and insect population limiters may have increased proportionally due to habitat fragmentation compared with less mobile species with similar ecological roles. Hence they may also have become more important in maintaining habitat patch quality

Predation is a major source of mortality, resulting in strong selection on strategies to avoid being captured. Individuals have access to multiple sources of information on predation risk: they can detect danger directly themselves, and they can attend to behavioural cues or warning signals produced by others. Rapid responses are vital when hunted by aerial predators in particular, as split-second decisions can mean the difference between life and death. I studied New Holland honeyeaters, Phylidonyris novaehollandiae, as a model system to examine how alarm calls encode information about danger and to understand how this information is used by receivers. In Chapter 2, observational data showed that these honeyeaters produce multi-element, aerial alarm calls in response to flying threats. Male honeyeaters had more opportunities to detect threats than did females and showed a greater propensity to alarm call when presented with gliding model predators. In Chapter 3, a combination of observational data and model presentations demonstrated that aerial alarm calls encode urgency in both the number of elements, with more dangerous threats receiving more elements, and the acoustic structure of the first element. Playback presentations of alarm calls and video recordings to measure responses revealed that honeyeaters made extremely fast decisions about fleeing to cover based on the acoustic structure of the first alarm element, while the number of elements determined for how long they hid. These two chapters demonstrate that receivers have rapid access to detailed information about the type and degree of danger from conspecific alarm calls. In Chapter 4, I investigated how birds integrate personal information about danger with social information from alarm calls. Perched birds were faster to detect model predators than feeding birds, suggesting that they have greater access to personal information. Consistent with this, perched birds were less likely to flee to cover in response to alarm playbacks than foraging birds. Birds also fled less in response to less urgent social information, such as playbacks of more distant alarm calls, and less relevant social information, in the form of calls from another species with overlapping but not identical threats. In Chapter 5, I tested how honeyeaters value social information about danger derived from single versus multiple sources, both within and across species. Birds paid attention to the number of independent signallers when assessing information from both conspecifics and heterospecifics, responding more strongly to playbacks of alarm calls from two sources than a single source, but they also moderated their responses according to signal relevance. Together, these results show that birds make flexible decisions about danger by integrating information from multiple sources and assessing its quality, allowing them to mitigate the costs of fleeing to false, or irrelevant, alarms while taking advantage of the multitude of information provided by the prey community's neighbourhood watch.

Foraging niche breadths of Singing Honeyeaters (Lichenostomus virescens) at two island sites - Rottnest Island and Garden Island, and two mainland sites - Swanbourne and Kellerberrin in south..-western Western Australia, were studied. The hypothesis that the island populations with larger Singing Honeyeaters (20% by weight), have a broader foraging niche than those on the mainland was tested by (i) analysis of foraging behaviour at each site, (ii) analysis of insect diet at each site, (iii) integration of these results to compare the foraging breadths of island and mainland populations. Replicated sites were matched on the basis of vegetation structure, which was analysed by levy pole count and plant species abundance. Except for the density of the lower height categories on Garden Island, the vegetation was successfully matched at all sites. Field trips from mid-spring (October) to early summer (December) recorded the foraging behaviour of the Singing Honeyeater under four categories-foraging plant, foraging height, foraging substrate and foraging behaviour. Results were summarised as the Shannon-Wiener test of niche breadth and also as J (evenness) values, giving an idea of how generalised each population is in relation to each dimension of foraging behaviour. These results showed that the island populations did have a broader foraging niche than the mainland populations which have a more specialised foraging niche breadth. (The Rottnest Island birds were also more generalised than the Garden Island birds). Foraging breadth was also determined through the analysis of droppings from Singing Honeyeater populations at Rottnest Island, and Kellerberrin (collected in the 1980's and 1990's) and Shark Bay (collected in spring 1994). Invertebrates from 10 different taxa were identified as well as a large proportion of fruit and seeds. These results showed that the island populations actually have a much narrower diet than those on the mainland, indicating a narrow foraging niche breadth. The contradiction in results may be due to several factors: i) the timing of dropping collection and the non-sequential recording of foraging observations at each study site; ii) the paucity of invertebrate taxa or abundance on Rottnest Island. However, the integration of foraging behaviour and diet analysis results is comparable. For example, the Singing Honeyeaters at Rottnest Island provided droppings with a high proportion of ant and wasp remains, and their behaviour included a large proportion of sallying and gleaning from the ground. Prey sizes determined from invertebrate remains concluded that the size of the bird has no relation to the size of prey taken. Kellerberrin birds took the largest prey, while Shark Bay and Rottnest Island populations took considerably smaller prey. Overall, it can be concluded that the island populations of Singing Honeyeater do have a broader foraging niche. Further research, such as the manipulative removal or addition of a competitive species to a mainland or island population respectively, is necessary to determine whether competition is the influencing factor on niche breadth. However, ethical considerations and a year­long study to determine seasonal interactions is essential prior to manipulative experimentation.

The New Holland honeyeater Phylidonyris novaehollandiae is a member of the family Meliphagidae, which is one of Australia's dominant passerine families (Ford and Paton, 1977). Many siu-dies have been conducted on this species in mainland Australia (e.g. Paton, 1981; 1982; McFarland, 1986) but there is much less data from Tasmania. This study was conducted near Hobart, Tasmania (S 42° 54' 10", E 147° 19' 26", average 50 m a.s.1). The site consisted of two adjacent habitats, one was dry sclerophyll forest and the other, a modified man-made habitat. The first stage of this study was the determination of time budgets. The activities of the New Holland honeyeater were found to be significantly different both seasonally and diurnally. The time proportion for foraging exceeded the time proportion for other activities throughout the year. The study also found that the major diet of this bird was nectar in all seasons of the year, while other non-nectar carbohydrate sources such as manna, lerp or honeydew were found to be less important in this study. The bird also spent a small proportion of their foraging time to feed on insects to satisfy their protein requiremeni's. . During the study on time budget activity, observations on various aspects of the breeding of the New Holland honeyeater were also conducted. The birds in this study had a lengthy breeding season from early winter to mid-summer. The birds were multi-brooded and the mean clutch 'size was 2.14 ±. 'S .E 0.13. The parental roles and nesting activity observed were similar to the earlier studies in mainland Australia. The second stage involved measurement of the basal metabolic rate. This was found to be higher (5.12 ± 0.14 ml g-1hr-1 ) than in the same species from mainland Australia probably because the colder climate in Tasmania is more energetically demanding, therefore the birds enhance their thermogenesis with an increased basal metabolic rate. The basal metabolic rate did not vary seasonally perhaps because the birds reside in a temperate climate and are prepared for the stress of changing seasons by making physiological and behavioural adaptations that allow the birds to survive throughout the year in Hobart, Tasmania. The third section deals with the time energy budget of the New Holland honeyeater. The time energy budget did not vary seasonally (153.95 -1- 4.5 in spring, 134.00 ± 7.5 in summer, 130.10 -± 10.7 in autumn and 123.00 1- 7.5 in winter) as the bird balance the time and energy allocation for their activities in facing the varying energy demands of their annual cycle.

The island state of Tasmania supports an environment unlike anywhere else in the country. Historically the land has been exposed to glacial conditions, been both isolated and attached to the rest of the continent. This has resulted in a unique array of flora and fauna. Of the birds species found in the state, 12 are endemic, and it is one of these species that is the focus of this study. Melithreptus affinis is one of two members of this genus found in Tasmania, both of which are endemic. It was first described in 1835, and although known to science, little if any research has been undertaken on any aspect of this species ecology. This study rectifies this. In a context of the Tasmanian environment, the foraging and time budget of M affinis was constructed. Literature has already shown that there are significant morphological differences between M affinis and the mainland M lunatus, species believed to be allopatric counterparts. In fact, within the genus, both the Tasmanian species show much greater morphological divergence than the mainland species. Results showed that M affinis used a wider variety of habitats, or increased niche during this study, with foraging effort being distributed between gleaning and probing methods. These variations were influenced by seasonal factors and climatic conditions, showing the adaptability of the study species, and how closely it has evolved with the Tasmanian environment. Versatility was demonstrated when environmental conditions were less than optimal. Continuing this broadening of niche is the species use of a wider array of microhabitats than records show for Melithreptids on the mainland. Microhabitat use was distributed between upper, mid and lower canopies, whilst this genus is generally considered and upper canopy specialists. Again these changes may be a response to the climatic conditions at the time of the study. To date the literature on the breeding biology of insular species is limited to a small body pertaining to Northern Hemisphere species. Characteristics such as lower clutch sizes, later laying dates, prolonged nestling development and increased adult survival have been attributed to island populations. This study on M affinis was undertaken to determine if such trends were consistent in a Tasmanian context. Analysis of both field data and museum specimens showed that there were no discemable differences in most aspects of reproduction. The characteristics shown by M affinis are consistent with other members of the genus, as well as other members of the Meliphagidae family, except the duration of the incubation period in the species. This period is longer than would be predicted based on other members of the family. It is hypothesised that this increase may be the result of a longer history of this species in Tasmania and thus an adaptation to the colder conditions experienced during the glacial periods. It is not possible to compare this characteristic with the other endemic species, as this information is not available. The lack of variation in the reproductive traits of this endemic species allows for this species to considered equivalent to continental species, and raises the question as to the validity of insular or island effects on other aspects of the species ecology. This species has evolved in isolation, in an environment that has undergone substantial geological alteration, and has evolved in response to these environmental conditions.

Bibliography: leaves 274-289.
xiii, 289 leaves : ill. ; 30 cm.
Title page, contents and abstract only. The complete thesis in print form is available from the University Library.
The mechanisms underlying the evolution of sexual size dimorphism in honeyeaters were investigated the Crescent Honeyeater, Phylidonyris pyrrhoptera. Ecological data was acquired at the Cromer Conservation Park, and Parndana, South Australia.
Thesis (Ph.D.)--Adelaide University, Dept. of Environmental Biology, 2001

The work presented in this thesis aimed to do the following : 1. investigate the cause of decline of the three Melithreptus species of the Mt Lofty Ranges, with a particular emphasis on M. gularis due to its critical status in the ranges ; 2. investigate the ecology and behaviour of sympatric M. brevirostris and M. lunatus populations in the Mt Lofty Ranges ; and 3. suggest management options for the three species. Further, it became clear through the course of the project that an understanding of the decline in Melithreptus required : 1. comparisons with other honeyeater species, particularly widespread and abundant honeyeater species. Three species of Melithreptus occur in the Mt Lofty Ranges : Brown - headed Honeyeater Melithreptus brevirostris ; White - naped Honeyeater Melithreptus lunatus ; and Black - chinned Honeyeater Melithreptus gularis. Since at least the 1970 ' s all three species have been in decline within the ranges. One species has been reduced in both abundance and distribution within the region ( M. gularis ), while the other two are now recognised as having reduced in abundance. Melithreptus species in the Mt Lofty Ranges are sympatric with strikingly similar ecology. Melithreptus gularis is the largest of the three, while M. brevirostris and M. lunatus are almost identical in weight, feeding behaviour and morphology. Despite their similarities no studies have closely examined their ecology in sympatry and no studies have examined possible causes of their decline. Interspecific competition is thought to be important in the organisation of honeyeater communities. Studies of nectarivore communities suggest a number of ways in which competition causes the component species to partition resources : size ; beak length ; habitat ; and behaviour, which includes a mix of social and feeding strategies. Due to its role in honeyeater community organisation, changed level of interspecific competition has been highlighted as a possible cause of decline in some honeyeater species in the woodlands of southern Australia. Both interference competition and exploitative competition have been highlighted in various situations ( Ford et al. 2001 ). Given the hypothesised role of interspecific competition in the decline of honeyeater species and the declining status of all the Melithreptus in the Mt Lofty Ranges the genus appeared to provide a good basis for examining the hypothesis that interspecific competition is contributing to the decline of some honeyeater species through exclusion from resources and / or reduction in resources available. ( Ford et al. 2001 ) give the following as potential tests for their interspecific competition hypothesis : 1. examine community structure for ' forbidden combinations ' ( pairs of species that rarely occur together ) ; 2. compare time spent in interspecific competition ( interference ), and foraging in fragmented and continuous habitat ; 3. measure seasonal and spatial patterns of resource abundance and depletion ; and 4. remove competitors and observe response in abundance and behaviour of other species. These suggestions form the basis for much of the work presented in this thesis. An initial survey examined not only community structure for forbidden combinations, but also investigated other possible causes of decline, based on literature for both declining woodland birds and Melithreptus. Besides interspecific competition, other possible causes included insufficient preferred habitat, insufficient food resources and landscape fragmentation. Repeated counts of honeyeaters at 90 sites of one hectare in the Mt Lofty Ranges were undertaken over a one year period. Melithreptus lunatus was found to be more abundant where certain eucalypt species occurred ( particularly E. viminalis ), although this was postulated to be a reflection of productive soils. Melithreptus brevirostris was found to be more abundant where Phylidonyris novaehollandiae ( New Holland Honeyeater ) was most abundant, despite P. novaehollandiae also being the most widespread and abundant honeyeater in the Mt Lofty Ranges. Thus, the survey work did not find forbidden combinations of honeyeaters. However , the scale at which the survey work was undertaken ( sites of 1ha ) may have masked any competition between species due to spatial heterogeneity. At the scale of one hectare there is likely to be areas of resource not used by other honeyeaters, allowing Melithreptus to avoid feeding territories of aggressive honeyeaters. Therefore, in order to more thoroughly investigate competition between P. novaehollandiae and Melithreptus, a removal experiment with finer resolution than 1ha was carried out. This demonstrated that P. novaehollandiae do prevent M. lunatus from using certain areas of the landscape. A final examination of interactions between Melithreptus and widespread and abundant honeyeaters was carried out in the form of a survey in which individual trees were watched and visits by honeyeater species timed. Based on observations of Melithreptus, it appeared that generally M. brevirostris groups used a swamping strategy to access defended resources, whereas M. lunatus moved quietly, often as individuals or pairs. Thus the two species were hypothesised to use two different behavioural strategies to access defended resources, termed stealth ( the use of secretive behaviour to access resources that are being protected ) and swamping ( the use of a combined direct approach by a number of individuals to access resources that are being protected ). Based on estimations of the standardised protection of resources for individual trees, M. lunatus were able to access defended resources for longer, while M. brevirostris were able to access better defended resources but for a shorter time. These results were consistent with the hypothesis of two different behavioural strategies for accessing defended resources. Both species may employ both strategies, but M. brevirostris more often use swamping, and M. lunatus more often use stealth. Investigating the morphology of the small honeyeaters of the Mt Lofty Ranges confirmed that size and beak length were important in discriminating between most species. However, these did not provide any basis for separating the Melithreptus. Closer examination of morphology between M. brevirostris and the M. lunatus sexes revealed further similarities to those previously documented. The average values for many morphological attributes of M. brevirostris fell between the average value for the M. lunatus sexes, suggesting that ecologically the three species / sexes formed a continuum. The M. lunatus sexes and M. brevirostris were then referred to as the small Melithreptus guild ( it was not possible to sex M. brevirostris based on the range of attributes measured ). The greatest differences between the small Melithreptus guild were found in wing length and leg morphology. The direction of the differences suggested that M. brevirostris would be more similar to female M. lunatus in movements and more similar to male M. lunatus in foraging behaviour. These two aspects of Melithreptus ecology were the subject of the last and most extensive phase of the project. Movements were investigated for Melithreptus at four sites in the Mt Lofty Ranges using radio - telemetry techniques. Melithreptus were found to use large areas of the landscape and to have large core areas of activity within their home range. Using the same methods confirmed that Melithreptus had larger home ranges ( mean 100 % minimum convex polygon 23 hectares ) than P. novaehollandiae ( mean 100 % MCP 5 hectares ), and larger home ranges than those reported in the literature for other honeyeater species. Data on a single M. gularis ( 100 % MCP 140 hectares ) suggest that this species has even larger home range requirements. Information from colour - banded birds suggests that most M. brevirostris and male M. lunatus had stable core areas of activity over the period of this study, while female M. lunatus were less likely to have stable core areas of activity, particularly during the non - breeding season. A trend in home range and movement data was consistent with the hypothesis that M. brevirostris was more similar to female M. lunatus than to male M. lunatus. Behaviour of Melithreptus and P. novaehollandiae were investigated using time budget techniques. Melithreptus were found to spend most of their day foraging ( up to 84 % ), very little time resting ( as little as 1.8 % ) and very little time in aggression ( as little as 0.6 % ). These values are each within the outer range of results published on other honeyeaters. Melithreptus gularis behaviour was very similar to both M. brevirostris and M. lunatus. Melithreptus appear to forage predominantly from poor quality resources, requiring a large proportion of their time allocated to foraging. The small proportion of time spent resting is probably a result of the time spent foraging. The small proportion of time spent in aggression is partly the result of a lack of aggression by Melithreptus, but is also potentially due to their knowledge of aggression levels within their home range and their use of stealth and swamping. Melithreptus are likely to avoid the most highly protected ( and therefore the most productive ) areas within their home ranges. A trend in behavioural data was consistent with the hypothesis that M. brevirostris was more similar to male M. lunatus than to female M. lunatus. Based on the data collected in this study, Melithreptus in the Mt Lofty Ranges are characterised by : relatively large home range size with core areas that are used over extended periods of time ; similar foraging behaviour and morphology ; lack of aggression ; and ( probably ( complex social behaviour. Their decline in the Mt Lofty Ranges can be attributed to the preferential clearance of their preferred habitat, their requirement for a large home range and their predominant use of poor quality resources, particularly in comparison to other, locally successful honeyeaters. The final aim of this work on Melithreptus honeyeaters in the Mt Lofty Ranges was to provide options for managing remaining Melithreptus populations, in particular M. gularis which according to informed observers is now critically endangered in the region. Due to the extent of habitat clearance in the Mt Lofty Ranges, the decline of Melithreptus will only be addressed in the long term through large scale revegetation projects. Melithreptus requirements in any large scale revegetation are most likely to be met by providing a range of eucalypt species. In the short to medium term, management actions may be needed to prevent the loss of M. gularis from the region. Given the findings of this study, there are few such options available. The management of woody weeds in known Melithreptus home ranges is suggested as one possible management strategy. Melithreptus rarely use a shrub layer for foraging, shelter or nesting, whereas P. novaehollandiae use a shrub layer for each of these activities. Thus, where grassy woodlands have been invaded by woody weeds, P. novaehollandiae potentially have an increased year round presence.
Thesis (Ph.D.)--School of Earth and Environmental Sciences, 2005.

The forests and woodlands of Victoria’s Box-Ironbark Region are one of the most important areas of animal diversity and significance in southern Australia. They provide critical habitat for a diverse array of woodland-dependant animals, including many threatened species such as the Squirrel Glider, Brush-tailed Phascogale, Regent Honeyeater, Swift Parrot, Pink-tailed Worm-lizard and the Woodland Blind Snake. Wildlife of the Box-Ironbark Country gives a comprehensive overview of the ecology of the box-ironbark habitats and their wildlife. It covers all of the mammals, birds, reptiles and frogs that occur in the region, with a brief description of their distribution, status and ecology, together with a distribution map and superb colour photograph for each species. The book includes a ‘Where to Watch’ section, featuring a selection of national parks, state parks and nature conservation reserves as places where people can experience the ecosystem and its wildlife for themselves. Wildlife of the Box-Ironbark Country is intended for land-managers, conservation and wildlife workers, land-holders, teachers, students, naturalists and all those interested in some way in learning about and appreciating the wildlife of this fascinating and endangered ecosystem.

Victoria's Box–Ironbark region is one of the most important areas of animal diversity and significance in southern Australia. The forests and woodlands of this region provide critical habitat for a diverse array of woodland-dependent animals, including many threatened and declining species such as the Squirrel Glider, Brush-tailed Phascogale, Regent Honeyeater, Swift Parrot, Pink-tailed Worm-Lizard, Woodland Blind Snake, Tree Goanna and Bibron's Toadlet. Wildlife of the Box–Ironbark Country gives a comprehensive overview of the ecology of the Box–Ironbark habitats and their wildlife, and how climate change is having a major influence. This extensively revised second edition covers all of the mammals, birds, reptiles and frogs that occur in the region, with a brief description of their distribution, status, ecology and identification, together with a detailed distribution map and superb colour photograph for each species. The book includes a 'Where to watch' section, featuring a selection of national parks, state parks and nature conservation reserves where people can experience the ecosystem and its wildlife for themselves. This book is intended for land managers, conservation and wildlife workers, fauna consultants, landholders, teachers, students, naturalists and all those interested in learning about and appreciating the wildlife of this fascinating and endangered ecosystem.