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Peter R. Mawson - One of the best experts on this subject based on the ideXlab platform.
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artificial hollows provide an effective short term solution to the loss of natural nesting hollows for carnaby s Cockatoo calyptorhynchus latirostris
Biological Conservation, 2020Co-Authors: Denis A. Saunders, Rick Dawson, Peter R. Mawson, Ross B CunninghamAbstract:Abstract The ecology of one breeding population of Carnaby's Cockatoo Calyptorhynchus latirostris has been studied at Coomallo Creek, Western Australia, since 1969. A wildfire destroyed breeding habitat in part of the study area and adjoining areas in late December 2009. An increase in the number of breeding attempts the following year suggested that hollows were probably limiting. From 2011, the number of hollows available to the Cockatoos was increased by repairing derelict natural hollows and providing artificial hollows. By 2017, Cockatoos had access to 87 natural and 68 artificial hollows the approximate dimensions of natural hollows. Artificial hollows were readily accepted, however there were significant differences in the probability of hollows being used due to location and land use type. Despite floor temperatures of black and white artificial hollows being warmer than those of natural hollows, there were no significant differences in the probability of hollow use, the probability of breeding failures, and nestling condition in either white or black artificial hollows or natural hollows. The number of breeding attempts rose from 52 in 2011 to 127 in 2016 indicating that management intervention was effective. Between 2011 and 2018, artificial hollows provided 45% of available hollows and 54% of breeding attempts were made in them. By 2018, the number of breeding attempts in the area was 112% higher than in 2011. Artificial hollows provide an excellent short-term solution to the continuing loss of natural hollows. However, without extensive re-establishment of breeding and foraging habitat, the future for Carnaby's Cockatoo is uncertain.
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a case study of environmental offsets for the endangered carnaby s Cockatoo calyptorhynchus latirostris
Pacific Conservation Biology, 2020Co-Authors: Brooke Richards, Miriam Sullivan, Peter R. MawsonAbstract:Environmental offsets are applied in Western Australia (WA) as a management tool to compensate for residual significant impacts of clearing and development of habitat for the endangered Carnaby’s Cockatoo (Calyptorhynchus latirostris). In the past 20 years many offsets have been established for the species. This research investigated whether environmental offsets were effective for conserving Carnaby’s Cockatoo habitat. The research was conducted as a case study describing offset implementation in WA based on 45 state-approved development proposals (2011–16) and 20 federally approved development proposals (2013–15). Land acquisition offsets were the most common type used for both WA- and federally approved developments. Only one offset that contributed to the 25 364 ha acquired has been vested as conservation estate. Land acquisition offsets allow development to occur without significant time delays, as developers have been able to use the transfer of funds for land purchase to fulfil most, or all, of their offset obligation(s). Those lands purchased by the Department of Biodiversity, Conservation and Attractions (and its predecessors) in fulfilment of offset conditions have been strategically acquired to either extend existing conservation estate, or to create a significant contiguous corridor of habitat suitable for Carnaby’s Cockatoos. Other offset types such as research and education were rarely used to fulfil offset obligations. There was free and easy access to online primary documentation associated with the granting of offsets, but secondary documentation was mostly unavailable and prevented in-depth investigation. Overall, mitigation of impacts on Carnaby’s Cockatoos from development of key habitat through environmental offsets shows promise, but thus far has resulted in a net loss of habitat for Carnaby’s Cockatoo.
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A case study of environmental offsets for the endangered Carnaby’s Cockatoo (Calyptorhynchus latirostris)
Pacific Conservation Biology, 2020Co-Authors: Brooke Richards, Miriam Sullivan, Peter R. MawsonAbstract:Environmental offsets are applied in Western Australia (WA) as a management tool to compensate for residual significant impacts of clearing and development of habitat for the endangered Carnaby’s Cockatoo (Calyptorhynchus latirostris). In the past 20 years many offsets have been established for the species. This research investigated whether environmental offsets were effective for conserving Carnaby’s Cockatoo habitat. The research was conducted as a case study describing offset implementation in WA based on 45 state-approved development proposals (2011–16) and 20 federally approved development proposals (2013–15). Land acquisition offsets were the most common type used for both WA- and federally approved developments. Only one offset that contributed to the 25 364 ha acquired has been vested as conservation estate. Land acquisition offsets allow development to occur without significant time delays, as developers have been able to use the transfer of funds for land purchase to fulfil most, or all, of their offset obligation(s). Those lands purchased by the Department of Biodiversity, Conservation and Attractions (and its predecessors) in fulfilment of offset conditions have been strategically acquired to either extend existing conservation estate, or to create a significant contiguous corridor of habitat suitable for Carnaby’s Cockatoos. Other offset types such as research and education were rarely used to fulfil offset obligations. There was free and easy access to online primary documentation associated with the granting of offsets, but secondary documentation was mostly unavailable and prevented in-depth investigation. Overall, mitigation of impacts on Carnaby’s Cockatoos from development of key habitat through environmental offsets shows promise, but thus far has resulted in a net loss of habitat for Carnaby’s Cockatoo.
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Implications of Banksia seed reward for conservation and management of Carnaby’s Cockatoo on the Swan coastal plain, Western Australia
Australian Journal of Zoology, 2020Co-Authors: Teagan R. Johnston, William D. Stock, Peter R. MawsonAbstract:The food resource utilisation of six species of Banksia by the endangered Carnaby’s Cockatoo (Calyptorhynchus latirostris) was investigated on the Swan coastal plain, Western Australia, over a 12-month period. The energy yield from the seeds harvested by the Cockatoos was determined and the information was combined with data on the number of infructescences produced per hectare, the average seed yield per infructescence and the average rate of harvest of that species of seed by the Cockatoos to calculate estimates of the number of infructescences required to support a single Cockatoo per day under a range of scenarios. Over 65% of infructescences of each species of Banksia handled by the Cockatoos were consumed for seed. Banksia sessilis had the largest number of infructescences and follicles manipulated by Carnaby’s Cockatoos. The energy content of Banksia seed was 20–23 kJ g–1. Seed weight varied from 0.075 ± 0.016 (s.e.) g for B. attenuata to 0.007 ± 0.002 (s.e.) g for B. sessilis. The number of infructescences required to meet the birds’ daily energy intake ranged from 14 for B. grandis to 3821 for B. sessilis. The results have important implications for the continued capacity of the Swan coastal plain to support Carnaby’s Cockatoos, for the future survival of obligate seeding Banksia spp. and for anthropogenic revegetation programs utilising Banksia spp.
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implications of banksia seed reward for conservation and management of carnaby s Cockatoo on the swan coastal plain western australia
Australian Journal of Zoology, 2019Co-Authors: Teagan R. Johnston, William D. Stock, Peter R. MawsonAbstract:The food resource utilisation of six species of Banksia by the endangered Carnaby’s Cockatoo (Calyptorhynchus latirostris) was investigated on the Swan coastal plain, Western Australia, over a 12-month period. The energy yield from the seeds harvested by the Cockatoos was determined and the information was combined with data on the number of infructescences produced per hectare, the average seed yield per infructescence and the average rate of harvest of that species of seed by the Cockatoos to calculate estimates of the number of infructescences required to support a single Cockatoo per day under a range of scenarios. Over 65% of infructescences of each species of Banksia handled by the Cockatoos were consumed for seed. Banksia sessilis had the largest number of infructescences and follicles manipulated by Carnaby’s Cockatoos. The energy content of Banksia seed was 20–23 kJ g–1. Seed weight varied from 0.075 ± 0.016 (s.e.) g for B. attenuata to 0.007 ± 0.002 (s.e.) g for B. sessilis. The number of infructescences required to meet the birds’ daily energy intake ranged from 14 for B. grandis to 3821 for B. sessilis. The results have important implications for the continued capacity of the Swan coastal plain to support Carnaby’s Cockatoos, for the future survival of obligate seeding Banksia spp. and for anthropogenic revegetation programs utilising Banksia spp.
Andrew A Biewener - One of the best experts on this subject based on the ideXlab platform.
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low speed maneuvering flight of the rose breasted Cockatoo eolophus roseicapillus i kinematic and neuromuscular control of turning
The Journal of Experimental Biology, 2007Co-Authors: Tyson L Hedrick, Andrew A BiewenerAbstract:SUMMARY 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.
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low speed maneuvering flight of the rose breasted Cockatoo eolophus roseicapillus ii inertial and aerodynamic reorientation
The Journal of Experimental Biology, 2007Co-Authors: Tyson L Hedrick, James R Usherwood, Andrew A BiewenerAbstract:SUMMARY 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 ( r 2 =0.55, P <0.00001), but greatly overestimated roll magnitude when applied with no roll damping. Non-dimensional roll damping coefficients of approximately –1.5, 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 ( r 2 from 0.2 to 0.37, 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 ( r 2 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.
William D. Stock - One of the best experts on this subject based on the ideXlab platform.
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Implications of Banksia seed reward for conservation and management of Carnaby’s Cockatoo on the Swan coastal plain, Western Australia
Australian Journal of Zoology, 2020Co-Authors: Teagan R. Johnston, William D. Stock, Peter R. MawsonAbstract:The food resource utilisation of six species of Banksia by the endangered Carnaby’s Cockatoo (Calyptorhynchus latirostris) was investigated on the Swan coastal plain, Western Australia, over a 12-month period. The energy yield from the seeds harvested by the Cockatoos was determined and the information was combined with data on the number of infructescences produced per hectare, the average seed yield per infructescence and the average rate of harvest of that species of seed by the Cockatoos to calculate estimates of the number of infructescences required to support a single Cockatoo per day under a range of scenarios. Over 65% of infructescences of each species of Banksia handled by the Cockatoos were consumed for seed. Banksia sessilis had the largest number of infructescences and follicles manipulated by Carnaby’s Cockatoos. The energy content of Banksia seed was 20–23 kJ g–1. Seed weight varied from 0.075 ± 0.016 (s.e.) g for B. attenuata to 0.007 ± 0.002 (s.e.) g for B. sessilis. The number of infructescences required to meet the birds’ daily energy intake ranged from 14 for B. grandis to 3821 for B. sessilis. The results have important implications for the continued capacity of the Swan coastal plain to support Carnaby’s Cockatoos, for the future survival of obligate seeding Banksia spp. and for anthropogenic revegetation programs utilising Banksia spp.
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implications of banksia seed reward for conservation and management of carnaby s Cockatoo on the swan coastal plain western australia
Australian Journal of Zoology, 2019Co-Authors: Teagan R. Johnston, William D. Stock, Peter R. MawsonAbstract:The food resource utilisation of six species of Banksia by the endangered Carnaby’s Cockatoo (Calyptorhynchus latirostris) was investigated on the Swan coastal plain, Western Australia, over a 12-month period. The energy yield from the seeds harvested by the Cockatoos was determined and the information was combined with data on the number of infructescences produced per hectare, the average seed yield per infructescence and the average rate of harvest of that species of seed by the Cockatoos to calculate estimates of the number of infructescences required to support a single Cockatoo per day under a range of scenarios. Over 65% of infructescences of each species of Banksia handled by the Cockatoos were consumed for seed. Banksia sessilis had the largest number of infructescences and follicles manipulated by Carnaby’s Cockatoos. The energy content of Banksia seed was 20–23 kJ g–1. Seed weight varied from 0.075 ± 0.016 (s.e.) g for B. attenuata to 0.007 ± 0.002 (s.e.) g for B. sessilis. The number of infructescences required to meet the birds’ daily energy intake ranged from 14 for B. grandis to 3821 for B. sessilis. The results have important implications for the continued capacity of the Swan coastal plain to support Carnaby’s Cockatoos, for the future survival of obligate seeding Banksia spp. and for anthropogenic revegetation programs utilising Banksia spp.
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foraging by carnaby s black Cockatoo in banksia woodland on the swan coastal plain western australia
Emu, 2016Co-Authors: Teagan R. Johnston, William D. Stock, Peter R. MawsonAbstract:Human–wildlife conflicts around the loss and use of habitat are common reasons for species being listed as threatened. In order to reduce such conflicts it is important to have a clear understanding of the resource requirements of threatened species and the environmental factors that influence the availability and continued supply of those resources. The availability of Banksia cones and temporal patterns of their use by Carnaby’s Black-Cockatoo (Calyptorhynchus latirostris), was measured bi-monthly in proteaceous woodlands of the Swan Coastal Plain, south-western Australia. Availability of Banksia cones was assessed at sites that differed in soil-types, time since last fire and occurrence of Phytophthora cinnamomi. The mean number of available cones differed significantly in relation to P. cinnamomi presence and time since last fire. This study revealed a strong association between availability of Banksia cones and their consumption by Carnaby’s Black-Cockatoo. Over 12 months, Carnaby’s Black-Cockatoos handled approximately half of the available Banksia cones, and over three-quarters of those handled involved feeding. Banksia attenuata and B. sessilis produced the greatest number of cones, with consumption proportionate to cone availability. Understanding the patterns of availability and consumption of food resources by Carnaby’s Black-Cockatoos provides critical pieces of information that will help implement more effective conservation and management to stem the decline of this species.
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time since fire influences food resources for an endangered species carnaby s Cockatoo in a fire prone landscape
Biological Conservation, 2014Co-Authors: William D. Stock, Leonie E Valentine, R P Fisher, Barbara Wilson, Tracy Sonneman, Patricia A Fleming, Richard J HobbsAbstract:Abstract Where threatened species persist in multiple use landscapes, management activities, such as prescribed burning, may influence the availability of resources for those species. We examined how time since fire can influence food resources for the endangered Carnaby’s Cockatoo (Calyptorhynchus latirostris) in banksia woodlands of southwestern Australia. Tree density and cone productivity of dominant plant species, Banksia attenuata and Banksia menziesii, were compared across 44 sites of varying post-fire aged vegetation. The number of Carnaby’s Cockatoos that could be supported in banksia woodlands was estimated using the bird’s energetic requirements and seed energy content. Banksia attenuata produced more cones at sites aged 10–30 years since fire in both survey years, while cone productivity for B. menziesii was highest in very old sites (>35 years since fire) in one year only. Higher numbers of Carnaby’s Cockatoos were predicted to be supported in vegetation aged between 14–30 years since fire, peaking in vegetation aged 20–25 years. The current distribution of post-fire aged vegetation within this area (>60% burnt within the last 7 years) is predicted to support ∼2725 Carnaby’s Cockatoos, representing 25–35% of the estimated birds reliant on the area. Our results indicate that food resources are influenced by time since fire and, consequently, if optimising food resources was an objective, may be manipulated by altering burning patterns. While human and asset protection is a priority for prescribed burning, management of landscapes for improved persistence of threatened species is also important and complex trade-offs will have to be considered.
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Pine as fast food: foraging ecology of an endangered Cockatoo in a forestry landscape.
PLOS ONE, 2013Co-Authors: William D. Stock, H. Finn, Jackson Parker, Ken DodsAbstract:Pine plantations near Perth, Western Australia have provided an important food source for endangered Carnaby’s Cockatoos (Calyptorhynchus latirostris) since the 1940s. Plans to harvest these plantations without re-planting will remove this food source by 2031 or earlier. To assess the impact of pine removal, we studied the ecological association between Carnaby’s Cockatoos and pine using behavioural, nutritional, and phenological data. Pine plantations provided high densities of seed (158 025 seeds ha−1) over a large area (c. 15 000 ha). Carnaby’s Cockatoos fed throughout these plantations and removed almost the entire annual crop of pine cones. Peak Cockatoo abundance coincided with pine seed maturation. Pine seed had energy and protein contents equivalent to native food sources and, critically, is available in summer when breeding pairs have young offspring to feed. This strong and enduring ecological association clearly suggests that removing pine will have a significant impact on this endangered species unless restoration strategies, to establish alternative food sources, are implemented.
Tyson L Hedrick - One of the best experts on this subject based on the ideXlab platform.
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low speed maneuvering flight of the rose breasted Cockatoo eolophus roseicapillus i kinematic and neuromuscular control of turning
The Journal of Experimental Biology, 2007Co-Authors: Tyson L Hedrick, Andrew A BiewenerAbstract:SUMMARY 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.
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low speed maneuvering flight of the rose breasted Cockatoo eolophus roseicapillus ii inertial and aerodynamic reorientation
The Journal of Experimental Biology, 2007Co-Authors: Tyson L Hedrick, James R Usherwood, Andrew A BiewenerAbstract:SUMMARY 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 ( r 2 =0.55, P <0.00001), but greatly overestimated roll magnitude when applied with no roll damping. Non-dimensional roll damping coefficients of approximately –1.5, 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 ( r 2 from 0.2 to 0.37, 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 ( r 2 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.
Rick Dawson - One of the best experts on this subject based on the ideXlab platform.
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artificial hollows provide an effective short term solution to the loss of natural nesting hollows for carnaby s Cockatoo calyptorhynchus latirostris
Biological Conservation, 2020Co-Authors: Denis A. Saunders, Rick Dawson, Peter R. Mawson, Ross B CunninghamAbstract:Abstract The ecology of one breeding population of Carnaby's Cockatoo Calyptorhynchus latirostris has been studied at Coomallo Creek, Western Australia, since 1969. A wildfire destroyed breeding habitat in part of the study area and adjoining areas in late December 2009. An increase in the number of breeding attempts the following year suggested that hollows were probably limiting. From 2011, the number of hollows available to the Cockatoos was increased by repairing derelict natural hollows and providing artificial hollows. By 2017, Cockatoos had access to 87 natural and 68 artificial hollows the approximate dimensions of natural hollows. Artificial hollows were readily accepted, however there were significant differences in the probability of hollows being used due to location and land use type. Despite floor temperatures of black and white artificial hollows being warmer than those of natural hollows, there were no significant differences in the probability of hollow use, the probability of breeding failures, and nestling condition in either white or black artificial hollows or natural hollows. The number of breeding attempts rose from 52 in 2011 to 127 in 2016 indicating that management intervention was effective. Between 2011 and 2018, artificial hollows provided 45% of available hollows and 54% of breeding attempts were made in them. By 2018, the number of breeding attempts in the area was 112% higher than in 2011. Artificial hollows provide an excellent short-term solution to the continuing loss of natural hollows. However, without extensive re-establishment of breeding and foraging habitat, the future for Carnaby's Cockatoo is uncertain.
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Satellite tracking of rehabilitated wild Baudin’s Cockatoos, Calyptorhynchus baudinii: a feasibility trial to track forest black Cockatoos
Pacific Conservation Biology, 2015Co-Authors: Lian Yeap, Rick Dawson, Anna Le Souef, C. Holyoake, Jill M. Shephard, Christine Groom, Tony Kirkby, Kristin S. WarrenAbstract: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 CockatoosthathadundergonetreatmentandrehabilitationatPerthZooandKaarakinBlackCockatooConservationCentre 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,250kmsouthfromthereleasesite.ThesuccessofthistrialopensthewaytoaddresskeyobjectivesintheForest 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.
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use of tree hollows by carnaby s Cockatoo and the fate of large hollow bearing trees at coomallo creek western australia 1969 2013
Biological Conservation, 2014Co-Authors: Denis A. Saunders, Peter R. Mawson, Rick DawsonAbstract:Abstract The loss of hollow-bearing trees and lack of replacements are important issues throughout the world where development of intensive agriculture has resulted in the reduction and fragmentation of natural woodlands. Many species of animal depend on hollows (cavities) for breeding and shelter, and are impacted by these changes. One such species is the endangered Carnaby’s Cockatoo Calyptorhynchus latirostris , an endemic of southwestern Australia, which nests in large hollows in eucalypt trees. Nest hollow selection by a breeding population at Coomallo Creek, in the wheatbelt of Western Australia, was studied from 1969 to 2013. The Cockatoos nested in any hollow large enough to access (mean entrance diameter 270 mm, floor diameter 407 mm and depth 1.24 m). Nesting attempts in shallow hollows ( 1000 mm). Breeding females returned to the same hollow they used previously, provided they had been successful in the previous breeding attempt and the hollow was not occupied. During the study, the Cockatoos used 252 large hollow-bearing trees. By 2013 40% of these had fallen or been pushed over, had been burnt deliberately or by wildfire, or had been damaged such that they were no longer suitable for use by the Cockatoos; an average annual loss rate of 0.91%. Based on this rate of loss, only 29% of large hollow-bearing trees standing in 2013 will be extant in 2125 and not all of these can be expected to offer useable nest hollows. The conservation implications arising from the results of the study are discussed.
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A proof of concept trial - Satellite tracking of Baudin's Cockatoos (Calyptorhynchus baudinii)
2013Co-Authors: Kristin S. Warren, Peter R. Mawson, C. Holyoake, Simone Vitali, H. Finn, Mike Calver, Lian Yeap, Jill M. Shephard, A. Le Souëf, Rick DawsonAbstract:This poster presents preliminary findings from a proof of concept trial for satellite tracking of Baudin’s Cockatoos. The study follows the work by Christine Groom, which is successfully demonstrating that Carnaby’s Cockatoos can be tracked using satellite transmitters, and a trial which involved attaching transmitter devices to captive black Cockatoos of all three species (Le Souef et al. 2013, in press). Two rehabilitated adult female Baudin’s Cockatoos were anaesthetised and fitted with tail-mounted satellite trackers and released in Kelmscott in September 2012. Prior to release, both birds were health checked and flight tested to demonstrate fitness for release. The movements of the Cockatoos were monitored according to Argos satellite transmissions, as well as ground truthing using flock sightings and reception of VHF signals from the satellite units using a radio telemetry antenna. According to their transmissions, the birds initially stayed in the Kelmscott area in close proximity to one another and other groups of Baudin’s Cockatoos in the area. However, after several days, one of the Cockatoos flew south and joined a flock of Baudin’s Cockatoos migrating further south. Interestingly, during this migration, this bird returned to the Serpentine area from which she was originally found injured. This bird currently remains in the Beela area, 140km southeast of Perth, with other Baudin’s Cockatoos. The second Cockatoo remained in the release area for several weeks before also moving south to Cardup, 33km southeast of Perth, where her transmitter was found two months later, still attached to the tail feathers which had possibly moulted out.
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Application of STR markers in wildlife forensic casework involving Australian black Cockatoos (Calyptorhynchus spp.)
Forensic Science International-genetics, 2011Co-Authors: Nicole White, Rick Dawson, Silvana R. Tridico, Peter R. Mawson, James Haile, Megan L Coghlan, Michael BunceAbstract:Parrots and Cockatoos are highly prized aviary birds and the demands for such species has fuelled their illegal trade and harvest from the wild. Here we report on three forensic case studies involving black-Cockatoos (Calyptorhynchus spp.) endemic to Australia. These cases involve suspected poaching and illegal killing of endangered red- and white-tailed black-Cockatoos. Through the prior development of 20 polymorphic microsatellite loci and population databases for white- and red-tailed black-Cockatoos, the tools are available to conduct high-resolution paternity and individual identity testing. In one case, we matched a red-tailed black-Cockatoo nestling to a tree hollow from which it was poached through the use of DNA from eggshell recovered from the nest. For the second case, we utilized our provenance population database (nest sites), and identified the kinship and geographic origin of a white-tailed black-Cockatoo, which was illegally harvested from the wild. The third case determined the number individual white-tailed black-Cockatoos allegedly shot at a fruit grower's orchard from body part remains. These genetic investigations highlight the significance and statistical confidence of DNA profiling and associated databases for endangered taxa, such as exotic birds. Our Cockatoo population databases are the first of their kind in Australia, and demonstrate the efficacy of such approaches to identify such illegal activity. With a robust set of genetic markers and methodologies in place, we aim to broaden our population databases to include other Cockatoo species of conservation concern.