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A 9-year-old female rose-breasted cockatoo (Eolophus roseicapilla) was presented for a humeral fracture. At presentation, the bird was severely lethargic and obese. On physical examination, an open right humeral fracture, healed left ulnar fracture, and intertarsal joint swelling were present. Results of hematologic testing and biochemical analysis revealed severe leukocytosis with heterophilia and increased creatine kinase and aspartate aminotransferase activities consistent with musculoskeletal lesions. Radiographs confirmed a right humeral fracture and showed severe polyostotic lytic and expansile lesions of the appendicular skeleton, as well as an enlarged hepatic silhouette. Surgical repair of the fracture was attempted, but the bird died during the procedure. Postmortem examination revealed severe bone deformities involving the fractured humerus, both ulnas, and the left tibiotarsus. Histologic findings were consistent with multiple intraosseous lipomas of the long bones and severe hepatic lipidosis. To our knowledge, this is the first report of multiple intraosseous lipomas in a bird. [ABSTRACT FROM AUTHOR]

The pathophysiology of heat illnesses in birds has not been well characterized. In this study, we describe the changes in heart rate, respiratory rate, blood biochemistry and histopathological findings in galahs and rock doves after heat exposure under standardized conditions designed to induce heatstroke. Birds in the heat-exposed group were exposed to environmental heat stress and compared to control birds. Both groups of birds were under general anaesthesia throughout the experiment and serial blood collections were performed for biochemical analyses, while organs were collected at the end of the experiment for histopathology. No electromyography traces consistent with the onset of heat cramps were observed in any of the birds. Biochemical changes suggestive of skeletal muscle and hepatocellular injury, including hyperkalaemia and increased serum muscle and hepatic enzyme activities, were often observed in heat-exposed galahs and rock doves at the onset of heatstroke. Microscopic analyses did not reveal any significant cardiac changes, although some lungs had signs of acute congestion. Some heat-exposed rock doves had microscopic changes indicative of necrosis in the pectoral muscle. There were significant hepatic changes in some heat-exposed galahs, but not in rock doves. This suggests that there may be species differences amongst birds in the organs most affected by heatstroke. The observed species differences in the physiological, biochemical and histopathological changes indicate that bird species should be studied separately for clinical syndromes such as heatstroke. RESEARCH HIGHLIGHTS Biochemical changes suggestive of skeletal muscle and hepatocellular injury in heat-exposed galahs and rock doves at the onset of heatstroke No electromyography traces consistent with the onset of heat cramps were observed Some heat-exposed rock doves had indications of necrosis in the pectoral muscle There were significant hepatic changes in some heat-exposed galahs [ABSTRACT FROM AUTHOR]

Avian orders differ in their thermoregulatory capabilities and tolerance of high environmental temperatures. Evaporative heat loss, and the primary avenue whereby it occurs, differs amongst taxa. Although Australian parrots (Psittaciformes) have been impacted by mass mortality events associated with extreme weather events (heat waves), their thermoregulatory physiology has not been well characterized. We quantified the upper limits to thermoregulation under extremely hot conditions in two Australian parrots: the mulga parrot (Psephotellus varius; ~55 g) and the galah (Eolophus roseicapilla; ~265 g). At air temperatures (Ta) exceeding body temperature (Tb), both species showed increases in Tb to maximum values around 43-44°C, accompanied by rapid increases in resting metabolic rate above clearly defined upper critical limits of thermoneutrality and increases in evaporative water loss to levels equivalent to 700-1000% of baseline rates at thermoneutral Ta. Maximumcooling capacity, quantified as the fraction of metabolic heat production dissipated evaporatively, ranged from 1.71 to 1.79, consistent with the known range for parrots, similar to the corresponding range in passerines, and well below the corresponding ranges for columbids and caprimulgids. Heat tolerance limit (the maximum Ta tolerated) ranged from 44 to 55°C, similar to the range reported for passerines, but lower than that reported for columbids and caprimulgids. Our data suggest that heat tolerance in parrots is similar to that in passerines. We argue that understanding how thermoregulatory capacity and heat tolerance vary across avian orders is vital for predicting how climate change and the associated increase in frequency of extreme weather events may impact avian populations in the future. [ABSTRACT FROM AUTHOR]

Before its 20th century expansion the Galah, Eolophus roseicapilla, was considered a bird of the inland but its pre-European distribution has received scant and only recent attention. Galahs were unknown to early colonists until explorers travelled deep into the Murray-Darling, Cooper and Diamantina catchments. They were later found around the Gulf of Carpentaria and in the southern Kimberley, Pilbara and deserts of Western Australia. European and indigenous sources accord that Galahs were not established in Central Australia until the closing decades of the 19th century. In 19th century South Australia Galahs occurred only in the far northeast, along the Diamantina and Cooper drainages, and indigenous language groups elsewhere generally had no name for them. Their reported occurrence in the Gawler Ranges appears erroneous. In the pre-European period, the three presently recognised subspecies existed as almost or actual allopatric populations, although it is likely that eastern E. r. albiceps was in contact with northern E. r. kuhli. We find that the Galah's range expansion was not entirely centrifugal, as previously assumed, because it occurred towards the centre as well as coastwards. [ABSTRACT FROM AUTHOR]

Conventional thinking for many years held that the holotype of the GalahEolophus roseicapilla, obtained in 1801 by the Baudin Expedition from France, was from south-eastern Australia. This did not mesh well with what is known of Galahs not having occurred in that part of Australia at that time. That it must have been a western bird is now strongly supported by bibliographic and morphological evidence. Our earlier phylogeographic study of the Galah had shown geographical structure in its mitochondrial DNA (mtDNA). We reasoned that if mtDNA could be extracted from the holotype the matter should be resolvable. We report the results of this work and affirm the case made from morphological and bibliographic data. [ABSTRACT FROM PUBLISHER]

Conventional thinking for many years held that the holotype of the Galah Eolophus roseicapilla, obtained in 1801 by the Baudin Expedition from France, was from south-eastern Australia. This did not mesh well with what is known of Galahs not having occurred in that part of Australia at that time. That it must have been a western bird is now strongly supported by bibliographic and morphological evidence. Our earlier phylogeographic study of the Galah had shown geographical structure in its mitochondrial DNA (mtDNA). We reasoned that if mtDNA could be extracted from the holotype the matter should be resolvable. We report the results of this work and affirm the case made from morphological and bibliographic data. [ABSTRACT FROM AUTHOR]

To evaluate the health and nutritional status of 3 wild Australian psittacine species, plasma and hepatic mineral concentrations and plasma biochemical values were measured in wild-caught galahs (Eolophus roseicapilla), long-billed corellas (Cacatua tenuirostris), and sulphur-crested cockatoos (Cacatua galerita). No correlations were found between hepatic and plasma mineral levels. Mean plasma calcium (1.79 mmol/L [7.16 mg/dL]) and sodium (103 mmol/ L [103 mEq/L]) concentrations were lower, whereas mean total phosphorus (6.53 mmol/L [20.22 mg/dL]) and potassium (8.87 mmol/L [8.87 mEq/L]) concentrations were higher than values for captive counterparts. Plasma iron levels were higher than those reported for captive counterparts, with evidence of interspecific (sulphur-crested cockatoos, 109 μmol/L [609 μg/dL]; corellas, 57 μmol/L [318 μg/dL]; galahs, 90 μmol/L [503 μg/dL]) and temporal variation (galahs: May, 107 μmol/L [598 μgldL]; July, 59 μmol/L [330 μg/dL]). Hepatic iron concentrations were as high as 1030 mg/kg. Interspecific variation was minimal in mean plasma selenium (11.8 μmol/L [929 μg/L]) and zinc (31.2 μmol/L [204 μg/dL]) concentrations. Plasma biochemical values varied significantly from reported reference ranges. Ranges for total protein, albumin, and bile acid concentrations were lower, whereas uric acid, glutamate dehydrogenase, amylase, and cholesterol concentrations were higher than those previously reported for these species, and interspecific variation was evident. Variation in measures of mineral status or plasma biochemical values between males and females were negligible. An evaluation of fecal microflora showed a distinct absence of gram-negative bacteria or budding yeast. Results of this study show that analyte values used to determine health and nutritional status of wild birds differ from those published for captive counterparts. Although analyte values appear to vary minimally by sex, distinct taxonomic and some temporal differences exist in values from wild birds of these 3 species. [ABSTRACT FROM AUTHOR]

Even in species in which males and females share a repertoire of calls, subtle sex differences in vocalisations often exist, particularly in calls used for long-distance communication. However, few studies address whether birds respond differently to similar male and female calls. This study investigated whether an Australian cockatoo, the Galah (Eolophus roseicapillus), responds differentially to three types of loud calls (Double Chet, Chechet and Chewp) commonly produced by both sexes. I played back male and female vocalisations to wild Galahs in Canberra, Australia, and recorded vocal and approach responses. Galahs responded differently to at least one call type, with birds approaching male Double Chets more closely but vocalising more to female Double Chets. Males were more likely than females to vocalise to Double Chets and Chechets, regardless of stimulus sex. These results suggest that males may have to expend more effort than females in forming affiliative relationships. Although males and females exhibited different vocal behaviour, paired males and females tended to approach stimuli together, which may indicate that coordination of movement, rather than coordination of vocal behaviour, is important in maintaining the pair-bond. These experiments show that even when the sexes share a repertoire, the sender and receiver sex may influence the nature of a vocal interaction. [ABSTRACT FROM AUTHOR]

Many hypotheses have been proposed to explain why in some species, males and females coordinate their behaviour to defend a territory. The sex of the individual initiating a joint display may shed light on the function of the display, but this variable has not been systematically explored. This study investigates whether male–female pairs in a socially monogamous cockatoo, the galah, respond differently to male-initiated and female-initiated joint threat signals, and whether one sex is more likely to initiate a threat response. Solo male defense calls, solo female calls, male-initiated paired calls, and female-initiated paired calls were presented to pairs of galahs at nest cavities during the pre-breeding season. Birds responded most strongly to female-initiated call bouts, regardless of the number of stimulus birds giving vocalizations. While paired birds coordinated their approach responses to the stimuli, males tended to initiate these responses. These results suggest that the sex of the initiating bird, rather than the number of calling birds, is most relevant to galahs when assessing threat near an active cavity. This study indicates that it is critical to consider the separate roles of the male and female in a joint display in order to fully understand that display's function. [ABSTRACT FROM AUTHOR]

When Europeans arrived in Australia, galahs were typically inland birds, quite sparsely distributed. Now they range from coast to coast, and are common. Why did this change occur? Why didn't it occur earlier? I argue that because galahs feed on the ground they found Australia's dominant inland grasses too tall to get at the seed, so relied on an agency to shorten them: Aboriginal grain cropping before contact, introduced stock after it. [ABSTRACT FROM AUTHOR]

There are several mechanisms for producing vocalizations that are similar to those of a conspecific, including song type matching during a vocal contest, group convergence on a signature call over time, or one-to-one matching of another individual''s signature call. A novel category of conspecific matching has been described in a parrot, the orange-fronted conure, Aratinga canicularis, which shows rapid and directional modification of vocalizations over the course of a single vocal interaction. We examined whether a geographically and phylogenetically distant parrot, the galah, Eolophus roseicapillus, uses similar rapid call modifications during contact call exchanges, and sought to better define the conditions under which wild parrots directionally modify their contact calls. In each trial, we interactively broadcast a single call exemplar recorded from wild galahs and recorded the vocal responses of nearby galahs. Temporal parameters of response calls converged on the stimulus over the course of an interaction. Frequency measures also showed convergence, although this effect was less pronounced. Male galahs were more vocally responsive overall, and birds tended to converge more closely on male stimuli over the course of an interaction. This experiment confirms that other parrots, in this case galahs, are capable of rapid, directional call modification, and we suggest that this vocal technique may be an efficient mechanism for mediating the fission–fusion social system that is characteristic of many parrot species. [Copyright &y& Elsevier]

The reconfigurable, flapping wings of birds allow for both inertial and aerodynamic modes of reorientation. We found evidence that both these modes play important roles in the low speed turning flight of the rose-breasted cockatoo Eolophus roseicapillus. Using three-dimensional kinematics recorded from six cockatoos making a 90° turn in a flight corridor, we developed predictions of inertial and aerodynamic reorientation from estimates of wing moments of inertia and flapping arcs, and a blade-element aerodynamic model. The blade-element model successfully predicted weight support (predicted was 88±17% of observed, N=6) and centripetal force (predicted was 79±29% of observed, N=6) for the maneuvering cockatoos and provided a reasonable estimate of mechanical power. The estimated torque from the model was a significant predictor of roll acceleration (r²=055, P<0.00001), but greatly overestimated roll magnitude when applied with no roll damping. Non-dimensional roll damping coefficients of approximately -15, 2-6 times greater than those typical of airplane flight dynamics (approximately -0.45), were required to bring our estimates of reorientation due to aerodynamic torque back into conjunction with the measured changes in orientation. Our estimates of inertial reorientation were statistically significant predictors of the measured reorientation within wingbeats (r² from 0.2 to 037, P<0.0005). Components of both our inertial reorientation and aerodynamic torque estimates correlated, significantly, with asymmetries in the activation profile of four flight muscles: the pectoralis, supracoracoideus, biceps brachii and extensor metacarpi radialis (r² from 0.27 to 0.45, P<0.005). Thus, avian flight maneuvers rely on production of asymmetries throughout the flight apparatus rather than in a specific set of control or turning muscles. [ABSTRACT FROM AUTHOR]

Maneuvering flight has long been recognized as an important component of the natural behavior of many bird species, but has been the subject of little experimental work. Here we examine the kinematics and neuromuscular control of turning flight in the rose-breasted cockatoo Eolophus roseicapillus (N=6), testing predictions of maneuvering flight and control based on aerodynamic theory and prior kinematic and neuromuscular studies. Six cockatoos were trained to navigate between two perches placed in an L-shaped flight corridor, making a 90° turn midway through each flight. Flights were recorded with three synchronized high-speed video cameras placed outside the corridor, allowing a three- dimensional reconstruction of wing and body kinematics through the turn. We simultaneously collected electromyography recordings from bilateral implants in the pectoralis, supracoracoideus, biceps brachii and extensor metacarpi radialis muscles. The cockatoos maneuvered using flapping, banked turns with an average turn radius of 0.92 m. The mean rate of change in heading during a complete wingbeat varied through the turn and was significantly correlated to roll angle at mid-downstroke. Changes in roll angle were found to include both within-wingbeat and among-wingbeat components that bear no direct relationship to one another. Within- wingbeat changes in roll were dominated by the inertial effects while among-wingbeat changes in roll were likely the result of both inertial and aerodynamic effects. [ABSTRACT FROM AUTHOR]

When approached by a potential predator, individuals must decide when to flee. Individuals could assess risk by monitoring their distance from an approaching threat or by monitoring the expected time that the predator would take to reach them. Theory predicts, and empirical studies support the hypothesis, that some species may maintain a temporal margin of safety and therefore monitor the expected time a predator would take to reach them. We systematically walked towards galahs, Cacatua roseicapilla, an Australian parrot, and varied our approach speed. If galahs maintain a temporal margin of safety, we expected them to flush at a greater distance in response to the fast approach. We found, however, no support for the temporal margin of safety hypothesis. Rather, we found evidence that galahs are sensitive to distance in a novel way: after being alerted, they flushed when humans approached to within 44% of the alert distance. Our result differs from traditional models of spatial margins of safety because it suggests that animals will take flight after being approached to within about half the alert distance. By doing so, individuals maintain a dynamic spatial margin of safety and may reduce costs associated with ongoing monitoring of predation risk. [Copyright &y& Elsevier]

Simple Summary: Cardiac diseases are a common finding in captive parrots. In this retrospective study, the cardiac silhouette of 36 wild galahs was measured in the ventrodorsal and laterolateral projections using radiographic images. The aim of the study was to determine reference values of the width and the length of the heart of wild galahs in relation to other anatomic landmarks. The evaluated reference indicates that the width of the heart is 50–65% of the thoracic width and 570–743% of the coracoid width. Background: Part of the diagnostic workup for cardiac diseases is radiographic imaging. To determine an enlarged heart, species-specific reference values are necessary. Wild birds are rarely diagnosed with cardiac disease, and only a few studies have been done to investigate the cardiac silhouette in wild birds. Methods: In this retrospective study, the cardiac silhouette of 36 wild galahs, presented at the hospital, was investigated in relation to other anatomic landmarks like the thoracic width, clavicula width, synsacrum width, distance between the third and fourth rib, distance of the clavicula, and length and height of the sternum using a digital DICOM viewer. Results: The cardiac width was significant compared to the thoracic width with a minimum to maximum of 50 to 65%. The cardiac width compared with the coracoid width also showed significant results with a minimum to maximum range of 570 to 743%. A significant correlation was found between the weight and the cardiac width and length. Conclusion: The cardiac silhouette in wild galahs is easily measured in both radiographic views, and the heart size can be compared to other anatomical landmarks. [ABSTRACT FROM AUTHOR]

The article discusses the survival strategies of parrot varieties including mulga (Psephotellus varius) and galahs (Eolophus roseicapilla) found in Death Valley in California. Also discusses the effect of temperature on their bodies, and strategy of parrots to evaporate water from their bodies to keep themselves cool.