Assessing capture and tagging methods for brolgas, Antigone rubicunda (Gruidae)
- Authors: Veltheim, Inka , Chavez-Ramirez, Felipe , Hill, Richard , Cook, Simon
- Date: 2015
- Type: Text , Journal article
- Relation: Wildlife Research Vol. 42, no. 5 (2015), p. 373-381
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- Description: Context Studies assessing welfare issues and efficiency of animal capture methods are important, as capture can pose a significant welfare risk and methods can be time consuming to develop. It is imperative to choose methods that minimise injuries, maximise capture rates and minimise time spent on capture. Aims To test methods of crane capture and tagging (transmitter, colour and metal band fitting), and to compare and develop safe and time efficient methods for capturing brolgas (Antigone rubicunda). Methods We tested three types of noose traps, cannon nets, clap-nets, spotlighting at night roosts and active pursuit of pre-fledged chicks. We also tested two band sizes and two transmitter attachment methods. We compared the success and capture efficiency of these methods and considered welfare issues by comparing the number of injuries and mortalities resulting from these methods. Key results We successfully captured brolgas with noose traps and a cannon net, and by using active pursuit of pre-fledged chicks. Noose traps became more efficient when deployed with call playback and taxidermy decoys. Australian noose traps and active pursuit of pre-fledged chicks were the safest methods with fewest injuries. Conclusions For maximum capture success with minimum injuries to target and non-target species, we recommend noose traps with call playback and taxidermy decoys for capturing adult and juvenile brolgas at feeding areas, and active pursuit for pre-fledged chicks at breeding sites. Noose lines should have elastic at both pegged ends, to avoid injuries. To minimise injuries from tagging, we recommend leg-band-fitted transmitters in preference to harness-fitted transmitters, Australian size 35 bands and colour bands with an internal diameter of 22mm. Implications The use of Australian noose traps with call playback and taxidermy decoys is a safe and time efficient method for capturing brolgas, and is also likely to work for other crane species. Our recommendations can help reduce capture-related mortalities and injuries to brolgas (and potentially other cranes), which is crucial, given the brolga is a threatened species. © 2015 CSIRO.
Breeding home range movements of pre-fledged brolga chicks, Antigone rubicunda (Gruidae) in Victoria, Australia - Implications for wind farm planning and conservation
- Authors: Veltheim, Inka , Cook, Simon , Palmer, Grant , Hill, F.A. Richard , McCarthy, Michael
- Date: 2019
- Type: Text , Journal article
- Relation: Global Ecology and Conservation Vol. 20, no. (Oct 2019), p. 17
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- Description: Built infrastructure, such as wind farms and power lines, can impair wildlife movement. These barriers may displace individuals from important habitats due to direct mortality or disturbance. Understanding animal movement patterns can help avoid such impacts and manage population level effects. Avoiding impacts and implementing mitigation strategies is difficult when movement and home range information is lacking. Impact at breeding sites may negatively affect population recruitment. The number of wind farm developments is increasing in southern Australia within the core range of the south-eastern brolga (Antigone rubicunda) population. The main threats to this wetland bird include habitat loss, chick predation and collisions with power lines and fences. Wind farms may increase collision and mortality risk, and habitat displacement but the impact is difficult to assess or mitigate, as movement patterns and home range size are unknown. We deployed 11 GPS transmitters on pre-fledged brolga chicks at breeding sites in 2010-2012, including one at a wind farm, to investigate movement and home range use of brolga chicks. Brolga chicks moved 442m on average, to and from night roost wetlands (range: 0m-1964 m). The average breeding home range was 232 ha, estimated with a Brownian bridge movement model at 95% UD, but varied greatly between individuals (70 ha-523 ha). Brolgas used either single or multiple wetlands, and those using multiple wetlands either switched between them or relocated permanently. Information from this study can be used to design turbine-free buffers at brolga breeding sites and to manage breeding wetlands. (c) 2019 Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).
Challenges faced by shorebird species using the inland wetlands of the East Asian-Australasian Flyway : The little curlew example
- Authors: Bellio, Mariagrazia , Minton, Clive , Veltheim, Inka
- Date: 2017
- Type: Text , Journal article , Review
- Relation: Marine and Freshwater Research Vol. 68, no. 6 (2017), p. 999-1009
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- Description: Asia is experiencing an alarming rate of inland wetlands loss, posing a risk to the future long-term survival of many species depending on these ecosystems. This review on the status and conservation of the little curlew (Numenius minutus) aims to draw attention to the conservation challenges faced by migratory shorebird species using the inland wetlands of the East Asian-Australasian Flyway (EAAF). Extensive and systematic research survey efforts along the EAAF have focused on species using coastal and tidal areas rather than on species using inland wetlands. Knowledge gaps include functional ecology and physiological responses to quality of food resources, population trends, migratory strategy and the role species play in supporting ecosystems resilience. Studies using remote sensing and geographic information system techniques to track the movements of birds along the flyway and to map habitat condition will prove essential in the future to allow a better understanding of the dynamics occurring at the stopover areas, how birds use resources and what competition pressures exist among species. Ultimately, these studies will contribute to our ability to predict changes and establish management practices for the long-term protection and conservation of the stopover areas for a suite of shorebird species using inland wetlands along the flyway. © CSIRO 2017.
Movements, Behaviour and Ecology of the Brolga, Antigone rubicunda, at multiple spatial and temporal scales
- Authors: Veltheim, Inka
- Type: Thesis , PhD
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- Description: The study of animal movement patterns, within and between habitats, is a key consideration in ecological and evolutionary disciplines. Movement studies address: where, when, why and how animals move and what scales are movements taken at? For example: when and how animals move in response to internal factors, such as the need to breed, or external factors such as weather? Understanding animal movements is crucial in conservation planning and management of species. My thesis aim was to understand brolga (Antigone rubicunda) spatial landscape use across their south-east Australian core range at multiple scales. The information presented in this thesis can be applied for conservation and management of the species. I deployed 23 GPS transmitters on adults (5), juveniles (6) and chicks (12) and used a range of modelling approaches, location data and behavioural data to study their movements. Modelling methods included: behavioural change point analysis, kernel density analysis and Brownian bridge movement models to estimate home ranges; Maxent to build a species distribution model, parametric compositional analysis to study habitat selection; Bayesian and frequentist linear models to investigate relationships between environmental variables and movements, habitat use and behaviour; and NicheMapperTM to understand ecophysiological drivers of movement behaviour. GPS-tracking revealed two seasonal movement strategies within the south-west Victorian brolga range with individuals moving either 100 km or 20 km on average, between non-breeding and breeding areas, depending on capture location. However, I found many exceptions to a strictly seasonal pattern of movement, suggesting brolgas have a flexible and adaptable movement strategy. Brolgas adopted a migratory or resident strategy, indicating that the south-west Victorian population is partially migratory. I investigated whether a dynamic species distribution model (dSDM), built with Maxent using short-term weather variables, could predict seasonal distribution and movements of brolgas at a landscape scale. Using GPS tracking data to validate the dSDM output, I demonstrated that the dSDM was useful for modelling occupancy and seasonal distribution, but did not explicitly capture movements at the scale the movements occurred. However, brolgas moved further and occupied highest suitable habitat available when predicted habitat suitability in south-west Victoria was low, suggesting brolgas track areas with high predicted habitat suitability. Dynamic species distribution models may be useful in identifying suitable habitat when overall habitat suitability within a species’ range is low. At the home range scale, I used the Brownian bridge movement model to estimate breeding home range size and parametric compositional analysis to determine habitat use and selection by brolgas. I expected wetland size, density and number of chicks in a clutch to influence home range sizes, however, found only weak evidence for greater home ranges with increased clutch size. Brolgas used either single or multiple wetlands within their home ranges, and those using multiple wetlands either switched between wetlands or relocated permanently. Within their breeding home ranges brolgas appeared to select against buildings and watercourses but showed no selection for land use type. At the daily scale, I focused on movement behaviour of brolgas between foraging areas in cropped paddocks and wetland roosts. I used a correlative and a mechanistic model to investigate the influence of thermoregulatory constraints and weather on daily movement decisions of brolgas. Movements between the two habitats were not driven by biophysical requirements. The results suggest brolgas tolerate a range of weather conditions before shifting habitats to reduce heat stress and metabolic costs or to maintain water balance. In this thesis, I discuss the ecological and conservation implications of my research findings. Finally, I also provide recommendations for avoiding wind farm impacts on the threatened south-west Victorian brolga population given my findings on daily, seasonal and annual movement patterns. Many studies have investigated wind farm impacts on birds. However, this is one of a few that considers all lifecycle stages, and takes a multi-site and -scale approach to studying bird movements to inform conservation and wind farm planning.
Partial migration of Brolgas (Antigone rubicunda) within a restricted range is revealed by GPS tracking
- Authors: Veltheim, Inka , Cook, Simon , McCarthy, Michael , Palmer, Grang , Hill, F.
- Date: 2022
- Type: Text , Journal article
- Relation: Emu Vol. 122, no. 1 (2022), p. 39-50
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- Description: No quantitative information exists on the movement patterns of Brolga, Antigone rubicunda (Gruidae) although the species is considered to undertake seasonal movements between breeding and non-breeding areas, and has been also described as both non-migratory and partly migratory. Information on this species’ movement behaviour is required to understand its basic ecology and inform conservation management across its range. Thus, we sought to investigate whether Brolgas in southern Australia undertake seasonal movements, to define routes travelled by individuals, and to clarify the species’ migratory status. Here, for the first time for this species, we quantified the distances travelled, timing of movements between breeding and non-breeding areas, and individual-level differences in movement patterns. We deployed GPS transmitters on five adults, six juvenile and 12 unfledged 6–9 week chicks in Victoria, Australia. Individuals were monitored for 71–646 days. These Brolgas showed partial migratory behaviour, with the south-west Victorian population including resident and migrating individuals, moving 6–30 km and 96–111 km between breeding and non-breeding areas respectively and some remaining resident throughout the year. Brolgas moved 1.6 km from roost to foraging areas on average throughout the year, the majority (95%) of these movements were within 5.2 km and overall Brolgas moved shortest distances during the non-breeding season. We discuss the main potential drivers for these movement patterns. These findings may assist local conservation planning and add to our understanding of Australian waterbird movements more broadly. © 2022 BirdLife Australia.