Black Cockatoo Research Articles

Museum specimens provide reliable SNP data for population genomic analysis of a widely distributed but threatened cockatoo species.

Natural history museums harbour a plethora of biological specimens which are of potential use in population and conservation genetic studies. Although technical advancements in museum genomics have enabled genome-wide markers to be generated from aged museum specimens, the suitability of these data for robust biological inference is not well characterized. The aim of this study was to test the utility of museum specimens in population and conservation genomics by assessing the biological and technical validity of single nucleotide polymorphism (SNP) data derived from such samples. To achieve this, we generated thousands of SNPs from 47 red-tailed black cockatoo (Calyptorhychus banksii) traditional museum samples (i.e. samples that were not collected with the primary intent of DNA analysis) and 113 fresh tissue samples (cryopreserved liver/muscle) using a restriction site-associated DNA marker approach (DArTseq™ ). Thousands of SNPs were successfully generated from most of the traditional museum samples (with a mean age of 44years, ranging from 5 to 123years), although 38% did not provide useful data. These SNPs exhibited higher error rates and contained significantly more missing data compared with SNPs from fresh tissue samples, likely due to considerable DNA fragmentation. However, based on simulation results, the level of genotyping error had a negligible effect on inference of population structure in this species. We did identify a bias towards low diversity SNPs in older samples that appears to compromise temporal inferences of genetic diversity. This study demonstrates the utility of a RADseq-based method to produce reliable genome-wide SNP data from traditional museum specimens.

Planning in the shadow of extinction: Carnaby’s Black cockatoos and urban development in Perth, Australia

ABSTRACT This paper explores the shifting ecological proximities of urban-human-animal relations in Perth via a story of Carnaby’s Black Cockatoos, urban planning and extinction. The story is framed around a challenge and a provocation. The challenge, calls for a deeper consideration of urban planning in the shadow of extinction. Such a consideration involves two entangled elements: a deepening ethical and practical engagement with diverse urban lifeforms and temporalities; and an exploration of the more-than-human communities that emerge, are threatened or made possible in extinction’s shadows. The provocation, involves asking questions about what kinds of responses to extinction in urban contexts are desirable, or even possible? The paper experiments with the concept of planning in and with ‘ethical time’ as one way of thinking about how commitments to urban nature and urban justice might be re-imagined in a time of mass extinction. With the help of Carnaby’s Black Cockatoos, I argue that planning multispecies cities requires re-setting coordinates for ethical decision-making, coordinates that are embedded in the rhythms, knots and relations of ecological time and in the responsibilities involved with living in more-than-human urban communities of difference.

Wandering and Wildflowering: Walking with Women into Intimacy and Ecological Action

Wandering and Wildflowering: Walking with Women into Intimacy and Ecological Action

Escaping from the City Means More than a Cheap House and a 10-Minute Commute

Escaping from the City Means More than a Cheap House and a 10-Minute Commute

Climate change indirectly reduces breeding frequency of a mobile species through changes in food availability

AbstractTrends of environmental change are influencing the behavior of many species across the world, while highly mobile species are disproportionately impacted by climate change and human modification. Here, we investigate the mechanisms behind climate change effects on the reproductive traits of highly mobile, West Australian bird taxa, the forest red‐tailed black cockatoo Calyptorhynchus banksii naso (FRTBC). Using a dataset of annual breeding frequency spanning 19 yr, in combination with hydrological, climatological, and remotely sensed data, we modeled the effects of environmental variation on the annual breeding frequency of FRTBCs. We found several significant relationships between annual breeding frequency of FRTBCs and environmental variation. While the model, which included a proxy for the availability of the cockatoo's primary food source and the previous season's rain, explained 49% of annual breeding frequency, there were also direct and indirect effects of heatwaves and forest productivity. Forest red‐tailed black cockatoo breeding appears to be linked to the spatiotemporal availability of its primary food sources, the fruit from the tree species, marri Corymbia calophylla and jarrah Eucalyptus marginata. However, Western Australia is experiencing significant climate change, with increases in temperature and declines in rainfall altering the phenologies of these species, while declining rainfall is affecting the vegetation structure of the region. As drought events and temperatures are anticipated to increase over the region, it is expected that the food resources during the breeding season for cockatoos will become increasingly limited in time and space, thus threatening the persistence of this iconic species. This scenario is likely to be representative of many other situations where wide‐ranging species rely on patchy food resources in a changing environment. As global biodiversity is increasingly threatened, this study presents timely evidence illustrating how climate change is affecting the persistence of a threatened, mobile species, and what the implications are for mobile species around the world.

Inference by exclusion in the red-tailed black cockatoo (Calyptorhynchus banksii).

Inference by exclusion is the ability to select a given option by excluding the others. When designed appropriately, tests of this ability can reveal choices that cannot be explained by associative processes. Over the past decade, exclusion reasoning has been explored in several non-human taxonomic groups, including birds, mainly in Corvids and Parrots. To increase our understanding of the taxonomic distribution of exclusion reasoning and, therefore, its evolution, we investigated exclusion performances in red-tailed black cockatoos (Calyptorhynchus banksii), an Australian relative of the Goffin cockatoo (Cacatua goffini), using a food-finding task. Cockatoos were required to find a food item hidden in 1 of the 2 experimenter's hands. Following training sessions in which they reliably selected the closed baited hand they had just been shown open, each individual was tested on 4 different conditions. Critical to demonstrating exclusion reasoning was the condition in which they were shown the empty hand and then offered a choice of both closed hands. The performance of all birds was above chance on all experimental conditions but not on an olfactory and/or cuing control condition. The results suggest that the birds might be able to infer by exclusion, although an explanation based on rule learning cannot be excluded. This first experiment in red-tailed black cockatoo highlights the potential of this species as a model to study avian cognition and paves the pathway for future investigations.

Assessing integration of black cockatoos using behavioral change point analysis

ABSTRACTEstablishing integration of an individual bird into a wild flock is particularly important in species that are highly gregarious and are reliant on the flock to increase their likelihood of survivorship. When individuals, rehabilitated and reintroduced to wild flocks, are tracked through satellite or global positioning system (GPS) telemetry, it is of further significance to establish integration to assess rehabilitation success and whether the individual can serve as a marker of the flock. To date, for black cockatoos (Calyptorhynchus spp.) this has been achieved through visual observations, which requires field‐based observations that may not be possible because of inaccessible terrain, or may be untenable because the tagged individual can move quickly or is cryptic within a given land cover type. To establish whether an individual had joined a flock, we proposed the use of behavioral change point analysis. Our analyses showed that for GPS data of 6 individuals of the 3 black cockatoo species endemic to Western Australia we could demonstrate behavioral differences in their movement paths that were either individual or flocked (integrated) behavior. We undertook field observations to validate integration into wild flocks. We characterized flocked behavior as a constant, repeated pattern at variable levels of velocity. Individual behavior manifested in 2 different forms: resident and exploratory behavior. The analysis showed that all birds had integrated into a wild flock within a month of release. Behavioral change point analysis is a useful method to characterize movement behavior in black cockatoos and to confirm their membership within a flock. Furthermore, confirmation of flock membership makes it possible to use the data from 1 tagged bird to indicate movement behavior at the flock level. © 2018 The Wildlife Society.

Effectiveness of biodiversity offsets: An assessment of a controversial offset in Perth, Western Australia

Environmental offsets are used increasingly as a conservation tool to balance demands of development and environment but there is little evidence that offsets are effective. Our study assessed the effectiveness of the offset package developed for the Roe Highway Extension, in Western Australia, for Carnaby's black cockatoo, red-tailed black cockatoo and southern brown bandicoot. Black cockatoos were accounted for in the offset requirements, while Southern brown bandicoots were accounted for in the mitigation requirements of the approval but not the offset requirements. The development was cancelled after partial clearing and has not been completed. Pre-development consultant surveys were examined in relation to the offset requirements. Fieldwork was conducted at the offset sites to ground-truth habitat qualities where possible. The offset package was then compared to the principles of Australian Commonwealth and State offset policies. We found the offset package did not completely satisfy Commonwealth or State offset requirements, showed inconsistencies with the policies and produced net loss of environmental value. The offset sites provided 64% of the black cockatoo habitat required by the Commonwealth offset requirements, and were of a lower quality. Similarly, undergrowth vegetation (<1 m; used by southern brown bandicoots) varied between the development and offset sites, indicating the offset proposal approval criteria ‘similar or better quality’ was not met. Like for like is not always required by offset legislation, but it was required in the approval criteria for this development project. The offset sites had previously been deemed unfit for development by the EPA, resulting in little additionality, a fundamental factor in ensuring true gains to compensate for the loss. To improve the suitability of offsets as a conservation tool we strongly encourage a checking process to confirm ecological outcomes of an offset, a contingency plan for if the offset doesn't provide sufficient ecological outcomes, greater consideration of requirements of species affected and stricter adherence to the wider principles of offsets. The use of biodiversity offsets is nearly inevitable given current development policies and processes; however, the application of offsets can be substantially improved to reduce further net loss of environmental value.

Yellow-tailed black cockatoos

Yellow-tailed black cockatoos

Curious creatures: a multi-taxa investigation of responses to novelty in a zoo environment.

The personality trait of curiosity has been shown to increase welfare in humans. If this positive welfare effect is also true for non-humans, animals with high levels of curiosity may be able to cope better with stressful situations than their conspecifics. Before discoveries can be made regarding the effect of curiosity on an animal’s ability to cope in their environment, a way of measuring curiosity across species in different environments must be created to standardise testing. To determine the suitability of novel objects in testing curiosity, species from different evolutionary backgrounds with sufficient sample sizes were chosen. Barbary sheep (Ammotragus lervia) n = 12, little penguins (Eudyptula minor) n = 10, ringtail lemurs (Lemur catta) n = 8, red tailed black cockatoos (Calyptorhynchus banksia) n = 7, Indian star tortoises (Geochelone elegans) n = 5 and red kangaroos (Macropus rufus) n = 5 were presented with a stationary object, a moving object and a mirror. Having objects with different characteristics increased the likelihood individuals would find at least one motivating. Conspecifics were all assessed simultaneously for time to first orientate towards object (s), latency to make contact (s), frequency of interactions, and total duration of interaction (s). Differences in curiosity were recorded in four of the six species; the Barbary sheep and red tailed black cockatoos did not interact with the novel objects suggesting either a low level of curiosity or that the objects were not motivating for these animals. Variation in curiosity was seen between and within species in terms of which objects they interacted with and how long they spent with the objects. This was determined by the speed in which they interacted, and the duration of interest. By using the measure of curiosity towards novel objects with varying characteristics across a range of zoo species, we can see evidence of evolutionary, husbandry and individual influences on their response. Further work to obtain data on multiple captive populations of a single species using a standardised method could uncover factors that nurture the development of curiosity. In doing so, it would be possible to isolate and modify sub-optimal husbandry practices to improve welfare in the zoo environment.

Long-term passive acoustic monitoring of Western Australian cockatoos

Carnaby’s black cockatoos (Calyptorhynchus latirostris) and forest red-tailed black cockatoos (Calyptorhynchus banksii naso) are threatened avian fauna endemic to Southwestern Australia. Both species vocalize during various activities including flight, foraging, feeding, and breeding, and their vocalizations are known to differ by age and gender. In this study, passive acoustic monitoring is employed to assist with ongoing monitoring and recovery efforts. Autonomous acoustic recorders are installed at two locations—an urban setting in the Swan coastal plains and a bushland setting in the Perth hills district. The urban setting is a well-known roosting site for Carnaby’s cockatoos. Noise from frequent aircraft activity is a dominant feature at the bushland setting. Call repertoires, established using visual sighting information, are used in developing automatic recognition algorithms for efficient processing of long-term recordings. In addition to providing information on population estimates, distribution, and demographics, the project aims to study the differences in call characteristics between the urban and bushland settings and establish a framework for observing potential seasonal changes in calling behavior.

Successional changes in feeding activity by threatened cockatoos in revegetated mine sites

Context Provision of key habitat resources is essential for effectively managing species that have specific ecological requirements and occur in production landscapes. Threatened black cockatoos in the jarrah (Eucalyptus marginata) forest of Western Australia have a wide range, so their conservation requires support from all land tenures, not just reserves. Mining in the jarrah forest temporarily removes cockatoo feeding habitat, so it is important to understand how cockatoos exploit revegetated areas for food resources. Aims We aimed to determine whether there were successional patterns in cockatoo feeding activity in revegetation aged from 4 to 23 years at three mine sites in the jarrah forest in south-western Australia. Methods We surveyed 232 plots in revegetation to document (1) structural and floristic variation in vegetation across mine sites and revegetation ages, (2) differences in cockatoo feeding activity across mine sites and revegetation ages on the basis of feeding residues and (3) any edge effect reflecting preferential use of vegetation at the interior or exterior of mine pits. We also documented the frequency of occurrence of cockatoo food plants and feeding residues in 480 plots in unmined forest to compare with revegetated areas. Key results Marri (Corymbia calophylla) and jarrah were commonly consumed in unmined forest and Banksia and Hakea species were also fed on to a lesser extent. Revegetated mine pits provided food within 4 years and continued to do so up until the oldest plots studied (23 years). The relative importance of food plants shifted from proteaceous species in young revegetation to myrtaceous species in intermediate to older revegetation. However, extent of feeding on myrtaceous species in older revegetation did not equate to feeding rates in unmined forest, with lower frequencies recorded in revegetation. Conclusions Black cockatoos fed in revegetation at all three mine sites, despite variations in vegetation age, structure and floristics. Feeding on proteaceous and myrtaceous food plants occurred within 4 and 7 years of revegetation being established, respectively, indicating that some food resources are restored quickly after mining disturbance of the jarrah forest. Implications Our results emphasise the importance of monitoring fauna recolonisation over appropriate time scales, to understand how successional processes in revegetation influence fauna population persistence in production landscapes.

Presentation and prognostic indicators for free-living black cockatoos (Calyptorhynchus spp.) admitted to an Australian zoo veterinary hospital over 10 years.

The veterinary records of three species of free-living, endangered black cockatoos (Calyptorhynchus spp.; n = 565) admitted to the Perth Zoo Veterinary Hospital in Western Australia during a 10-yr period (2000-09) were analyzed to determine the effect of clinical presentation and treatment on survival to release. The most-common reason for admission was trauma (at least 76.7% of cases), and trauma was also the most-frequent finding on necropsy examination (80.1% of cases). Anemia and paralysis-paresis were significant factors determining the decreased likelihood of survival of cockatoos undergoing rehabilitation. Human activities, in particular vehicle strike, were significant causes of morbidity and mortality in free-living black cockatoo populations.

Satellite tracking of rehabilitated wild Baudin’s cockatoos, Calyptorhynchus baudinii: a feasibility trial to track forest black cockatoos

Baudin’s cockatoo, Calyptorhynchus baudinii, is a threatened forest black cockatoo species, endemic to the south-west of Western Australia. In this study we fitted tail-mounted satellite transmitters to two female Baudin’s cockatoos that had undergone treatment and rehabilitation at Perth Zoo and Kaarakin Black Cockatoo Conservation Centre to investigate the feasibility of satellite tracking this species. Both birds were released in Kelmscott, Perth, into an area frequently visited by a flock of wild Baudin’s cockatoos. Both telemetry units provided reliable datasets, with one bird moving ~250 km south from the release site. The success of this trial opens the way to address key objectives in the Forest Black Cockatoo Recovery Plan, including: postrelease survival of rehabilitated birds, flock movement, habitat use, and the identification of critical feeding and breeding habitat. Most importantly, it demonstrates that satellite transmitters can be successfully used to locate and track forest black cockatoo species, which are otherwise difficult to monitor.

Characteristics of nest trees and nest hollows used by the forest red-tailed black cockatoo (Calyptorhynchus banksii naso) in south-west Western Australia: comments on Johnstone et al. (2013)

Johnstone et al. (2013) (Pacific Conservation Biology 19, 122–141) make a substantial contribution to the knowledge of the forest red-tailed black cockatoo (Calyptorhynchus banksii naso) (FRTBC), presenting data on nest hollows and nest tree attributes. They discuss the threats to the current and future breeding hollows and conclude that ‘we are facing a major crisis in southern forests’. Although there are sound reasons for concern over the conservation of cockatoo species, the imminence of a crisis is not established by the data presented. We provide spatial and management context and present data relevant to discussion of threats to FRTBC hollows in south-west Western Australia. The primary strategy for providing habitat across the publicly owned forests is reservation, which formally excludes timber harvesting from more than 50% (1.3 million ha) of the forest, informally protects a further 11%, and protects habitat trees within harvested areas. Timber harvesting in these forests generally involves partial cutting, which retains trees of a wide range of size and age classes. A realistic minimum age for trees bearing hollows used by FRTBC in the jarrah (Eucalyptus marginata) forest is ~120–150 years (trees diameters of 50–60 cm), well below the 209 years highlighted by Johnstone et al. (2013). Most nest hollows occur in intermediate-sized trees. Clustering of FRTBC nest trees was not demonstrated in their data but is worthy of further investigation. Improved estimates of nest tree availability and loss would provide perspective on the threats to FRTBC, as would knowledge of population size and age structure of the FRTBC. The protection of known nest trees and control of feral competitors, where possible, would benefit FRTBC.

Identifying conservation units after large‐scale land clearing: a spatio‐temporal molecular survey of endangered white‐tailed black cockatoos (Calyptorhynchus spp.)

AbstractAimWe examined how the threatened and endemic white‐tailed black cockatoos of Western Australia have responded genetically to recent and comprehensive habitat loss with the ultimate aim of identifying units for conservation. We assessed the population structure, connectivity and genetic diversity at spatial and temporal scales for Calyptorhynchus baudinii and C. latirostris, which have undergone dramatic population declines. Genetic comparisons of pre‐ and post‐population decline were carried out by including historical samples dating back to 1920. We examined samples collected from across 700 km of their distribution and sampled approximately 1% of the current population census size to produce significant insights into the population genetics of white‐tailed black cockatoos and generate genetic information crucial for conservation management.LocationSouthwest corner of Western Australia.MethodsSix hundred and eighty‐four cockatoo samples were collected from 1920 to 2010 and profiled with 19 microsatellites to identify spatial population structure and loss of genetic diversity.ResultsThe temporal and spatial microsatellite data illustrated that the geographically defined genetic structuring in white‐tailed black cockatoos is likely to represent a recent phenomenon. We identified: (1) spatial population substructure east and west of extensively cleared habitat (&gt;95,800 km2), but the historical samples clustered with the current western population, regardless of origin, (2) a regional loss of allelic diversity over 3–4 generations for the current eastern population, (3) a lack of a genetic signal of the recent population decline, but perhaps a mid‐Holocene population collapse and lastly, (4) limited genetic differentiation between the two currently recognized white‐tailed black‐cockatoo species suggests a review of taxonomy and/or management units should be undertaken.Main conclusionBased on extensive spatio‐temporal sampling, we have demonstrated that recent anthropogenic habitat modifications have affected the genetic structure of a long‐lived and highly mobile species. Our results have identified areas of high conservation value and the importance of maintaining native vegetation migration corridors.

One fledgling or two in the endangered Carnaby's Cockatoo (Calyptorhynchus latirostris): a strategy for survival or legacy from a bygone era?

Of the five species of black cockatoo in the genus Calyptorhynchus, those species with red tail bands (Red-tailed Black Cockatoo and Glossy Black Cockatoo) lay clutches of only one egg and those with white or yellow tail bands (Carnaby's Cockatoo, Baudin's Cockatoo and Yellow-tailed Black Cockatoo) usually lay clutches of two. The breeding of the endangered Carnaby's Cockatoo has been studied from 1969 to 2012 at a number of localities throughout its range in south-western Australia within a region largely cleared for agriculture. When raising nestlings the species feeds on seeds of native vegetation, and there was a strong but not significant negative relationship between nesting success and percentage loss of native vegetation within 6 and 12 km of nest hollows. There was a significant negative relationship between the health of nestlings and percentage loss of native vegetation around nest hollows. While the usual clutch size is two, average clutch size tended to be lower in areas where much native vegetation has been cleared. While both eggs hatch in 77% of two-egg clutches, the species normally fledges only one young. However, the species is capable of fledging both nestlings from a breeding attempt. Sets of siblings are usually the product of older, more experienced females nesting in areas where more native vegetation has been retained. The conservation implications of these findings are discussed in the light of predicted changes to the climate of south-western Australia.

Attachment and performance of Argos satellite tracking devices fitted to black cockatoos (Calyptorhynchus spp.)

Context Studying interactions between a wildlife species and its spatial environment can enable a deeper understanding of its ecology. Studies of spatial ecology are generally undertaken by attaching tracking devices to selected individuals and following their movements. Highly mobile species, such as black cockatoos (Calyptorhynchus spp.), that occupy habitats with patchy resources are ideal candidates. The powerful beak and chewing habits of black cockatoos make it difficult to successfully attach tracking devices to them. Aims We developed a safe technique for attaching tracking devices to black cockatoos and assessed the impact of the tracking devices, as well as their performance in relation to battery life, retention time and accuracy of location fixes. Methods We describe a technique for attaching Telonics (Mesa, AZ, USA) Argos Avian Transmitter TAV 2617 tracking devices to the two central tail feathers of black cockatoos. Key results Of 26 tracking devices fitted (24 to Carnaby’s cockatoos, C. latirostris; two to Baudin’s cockatoos, C. baudinii), 20 exhibited longer retention time than the nominal battery life. One tracking device was chewed until it was non-functional before release and two were presumed chewed after release because their tracking devices failed prematurely. There was no evidence that the tracking devices inhibited the flight capability of cockatoos. The performance of the Argos tracking devices exceeded expectations with regard to retention times, battery life and overall accuracy of location fixes. The tracking devices enabled detection of instances of rapid long-distance movements, including one bird that travelled 70 km between night roosts while migrating. Most study birds (68%) remained within 50 km of their release sites while monitored. Conclusion The tracking devices were a suitable choice for black cockatoos and for the purpose of this study. They posed minimal snag risk, were of suitable dimensions for tail attachment and they enabled data to be collected even if birds dispersed long distances. The main limitations that must be considered when assessing their suitability for future research projects are the errors associated with location fixes, limited retention time in relation to moulting of tail feathers and limited battery life. Implications The development of a method for successfully attaching tracking devices to black cockatoos opens the possibility to study aspects of the ecology of black cockatoos and other highly mobile species that was not previously possible.

Hematologic and Plasma Biochemical Reference Values for Three Species of Black Cockatoos (Calyptorhynchusspecies)

Black cockatoos in southwest Western Australia face population declines as a result of habitat loss and fragmentation, poaching, competition with other species, vehicle strikes, and shootings. In this study, hematologic and plasma biochemical reference values were determined for 3 endemic Western Australian black cockatoo species: Carnaby's cockatoo (Calyptorhynchus latirostris) (n = 34), Baudin's cockatoo (Calyptorhynchus baudinii) (n = 22), and forest red-tailed black cockatoo (Calyptorhynchus banksii naso) (n = 22). Significant sex-related differences were detected in Carnaby's cockatoos, and differences were also found among the 3 species. The forest red-tailed black cockatoos showed a markedly greater eosinophil count than did the 2 white-tailed species. Blood values from samples obtained by different collection methods differed significantly for Carnaby's cockatoos, which indicates that anesthesia may affect analyte values and that collection methods should remain consistent. The results of this study will be useful for clinically evaluating wild black cockatoos that are undergoing rehabilitation for release and will provide baseline data for future investigations of free-living black cockatoo health.

Feeding activity of threatened black cockatoos in mine-site rehabilitation in the jarrah forest of south-western Australia

Land clearing threatens three black cockatoo species (forest red-tailed black cockatoo, (Calyptorhynchus banksii naso), Carnaby’s cockatoo (Calyptorhynchus latirostris), and Baudin’s cockatoo (Calyptorhynchus baudinii) endemic to south-western Australia, so revegetation is important to their recovery. Over three years we studied cockatoo activity in 7–14-year-old mine-site rehabilitation in the region’s jarrah (Eucalyptus marginata)–marri (Corymbia calophylla) forest to give the most detailed description to date of the use of rehabilitation by the birds. Pits varied floristically and structurally (despite similar rehabilitation prescriptions), but interior and exterior plots (100 m2) were similar within pits. Using feeding traces (e.g. chewed husks), and behavioural observations we confirmed feeding within eight years of revegetation. Plots containing feeding trace were similar to plots without, so factors determining black cockatoo feeding may not be apparent at small scales. Returning food resources reflected vegetation succession, with regenerating marri and fast-maturing proteaceous species providing most food. Carnaby’s cockatoo ate Banksia and Hakea seeds and Baudin’s cockatoo and the forest red-tailed black cockatoo consumed marri seeds. Banksia squarrosa, Hakea undulata, H. prostrata and marri were common foods in all years. Revegetation efforts elsewhere should consider these species, within the constraints of rehabilitation protocols addressing multiple aims.