- The Australian kangaroo industry: male only harvesting, sustainability and an assessment of animal welfare impacts
- The perils of being populous: Control and conservation of Abundant Kangaroo Species
- Improving the humaneness of commercial kangaroo harvesting
- Harvest Management of Kangaroos During Drought
- Kangaroo Genetics: Impacts of Harvesting
- Kangaroo Industry Wild Game Training Initiative
- A model for assessing the relative humaneness of pest animal control methods
- Predicting the distribution of Eastern Grey Kangaroos by remote sensing assessment of food resources
- A history of the debate (1948-2009) on the commercial harvesting of kangaroos, with particular reference to New South Wales and the role of Gordon Grigg
- Conservation benefit from harvesting kangaroos: status report at the start of a new millennium: A paper to stimulate discussion and research
- Commercial kangaroo harvesters handbook NSW
- Commercial kangaroo harvesting fact sheet
- Monitoring Kangaroo Populations in Southeastern New South Wales
- An overview of the Queensland macropod monitoring programme
- Repeatability of aerial surveys
- Potential Use of Radiometric Data for Wildlife Habitat Modelling
- The effect of non-sex biased shooting on some population characteristics of the Eastern Grey Kangaroo in the Murrurundi area, New South Wales
- Subsidized Commercial Harvesting for cost-effective wildlife management in urban areas: a case study with kangaroo sharpshooting
- Accuracy and consistency in the aerial survey of kangaroos
- Accounting for animal density gradients using independent information in distance sampling surveys
- Using kangaroo surveys to monitor biodiversity
- Fertility control in female eastern grey kangaroos using the GnRH agonist deslorelin.2. Effects on behaviour
- Population monitoring for kangaroo management
- Fertility control in female eastern grey kangaroos using the GnRH agonist deslorelin. 2. Effects on behaviour
The Australian kangaroo industry: male only harvesting, sustainability and an assessment of animal welfare impacts
(McLeod & Sharp, 2020)
The purpose of this study was to look closely at the impacts that this policy change had on several issues: the welfare of kangaroos; the sustainability of commercial kangaroo harvesting; the population dynamics of kangaroos; and the attitudes and perceptions of landholders. The methods used to address these issues include the following: expert assessment of the animal welfare impacts of commercial harvesting practices and comparing commercial harvesting with other methods of managing kangaroos; a review of the ecological sustainability of harvesting; simulation modelling to predict the long-term effects on kangaroo populations and the environment; and a survey of landholder attitudes toward the male-only harvesting policy.
The perils of being populous: Control and conservation of Abundant Kangaroo Species
(Croft & Witte, 2021)
Australia’s first people managed landscapes for kangaroo species as important elements
of their diet, accoutrements and ceremony. This developed and persisted for about 65,000 years. The second wave of colonists from the United Kingdom, Ireland and many subsequent countries introduced familiar domesticated livestock and they have imposed their agricultural practices on the same landscapes since 1788. This heralded an ongoing era of management of kangaroos that are perceived as competitors to livestock and unwanted consumers of crops. Even so, a kangaroo image remains the iconic identifier of Australia. Kangaroo management is shrouded in dogma and propaganda
and creates a tension along a loose rural–city divide. This divide is further dissected by the promotion of the consumption of kangaroo products as an ecological good marred by valid concerns about hygiene and animal welfare. In the last decade, the fervour to suppress and micromanage populations of some kangaroo species has mounted. This includes suppression within protected areas that have generally been considered as safe havens. This review explores these tensions between the conservation of iconic and yet abundant wildlife, and conflict with people and the various interfaces at which they meet kangaroos.
McLeod, Steven R & Sharp, Trudy MRIRDC Publication No. 13/116 (June 2014)
The overarching project objective was to provide scientific knowledge and other information on the animal welfare impact of kangaroo harvesting methods, with the aim of determining the most appropriate euthanasia methods for young kangaroos to reduce, as much as possible, unnecessary pain, distress and suffering. The project focused on evaluating the current methods of euthanasia of pouch young and determining the fate of orphaned young at foot that escape euthanasia. The research found that the current euthanasia methods, when applied correctly, can be effective and humane but there is some room for improvement. The results indicated that bringing the head into contact with a stationary object, such as the tray of the shooters vehicle, is the most effective method available. Young-at-foot are very mobile and gunshot is the most suitable method for euthanizing them.
(Pople A. R., 2003)
This NSW report addresses concerns of overharvesting of kangaroos during drought. A simulation model was used to assess the risk of overharvest during drough and assessed the potential indicators and thresholds for population decline and overharvesting.
This research addressed concerns about the effect of harvesting on the genetics of kangaroo species and found that the effects of commercial harvesting were unlikely to produce genetic changes in the population.
(Mawson, 2011)RIRDC Publication No. 11/123 (2011)
The Queensland Government convened a Kangaroo Industry Development Committee (KIDC) following the suspension of kangaroo exports to Russia in 2009 and one of the committee’s recommendations was that the immediate and long term training needs of the industry required attention, particularly for field harvesters. The project involved the development and conduct of a national training program for accredited wild game harvesters, the development of an assessment tool and the development of national competency standards in field harvesting, depot operations and industry processor establishments. This report summarises the purpose and results from the training initiative. This report includes samples of the training materials developed.
(Sharp & Saunders, 2011)
This report was produced through a project funded to develop a suitable, workable model for assessing the relative humaneness of pest animal control methods. The assessment of overall welfare impact is based on five domains:Thirst/hunger/malnutritionEnvironmental challengeInjury/disease/functional impairmentBehavioural/interactive restrictionAnxiety/fear/pain/distressThe model was not designed to provide an absolute measure but to allow a judgement go be made about the impact of a specific control method on the target animal. It provides a reliable, functional and accepted method that enables humaneness to be considered as an integral part of planning invasive animal control.
Predicting the distribution of Eastern Grey Kangaroos by remote sensing assessment of food resources
(Rollings & Moss, 2016)
This study demonstrates how the distribution of animals can be described using remotely sensed data at a scale in the order of square kilometers. Kangaroo distribution has been monitored at regional scales using aerial surveys and detailed field study. This study attempts to fill the gap between local and regional scales by using Landsat derived vegetation characteristics to provide animal distribution details at local scale. Field surveys of Eastern Grey kangaroos and vegetation biomass were undertaken at the Warrumbungle National Park, New South Wales, Australia. The distribution and abundance of kangaroos and plant biomass were compared with remotely sensed vegetation characteristics taken from Landsat TM imagery.
A history of the debate (1948-2009) on the commercial harvesting of kangaroos, with particular reference to New South Wales and the role of Gordon Grigg
The harvesting of kangaroos has arguably been the most vexatious wildlife management issue in Australia. This paper traces the post-World War II debate over kangaroo management, and how the various parties have managed the issue to arrive at the current levels of kangaroo harvest, with particular reference to NSW and the transition of policy from culling kangaroos as an agricultural pest to a commercial harvest as the principal driver. Kangaroos have been variously represented in the debate as pests, a commercial resource, an iconic Australian symbol, and endangered species. In 1958, kangaroos narrowly survived a pastoralists’ vote to list them as noxious animals. If it had passed, and been agreed upon by State Cabinet, it would have made it compulsory for landowners to rid their land of these animals because they would then have been noxious species. Over 1964 and 1965, culled kangaroo populations crashed during drought. It showed that for kangaroo management to be effective in the long-term the original tenet in the Fauna Protection Act 1948 of kangaroos as pests had to be re-interpreted and, in Allen Strom’s words: “kangaroos needed to be managed on a sustained yield basis.” Fifty years later the debate is better informed, with a sustainable population management approach, which includes commercial harvesting.This paper explores the history of all the key research, researchers and policy makers regarding kangaroo management over the last forty years.The modern debate now centres on matters of ethics and animal welfare on the one hand, and conservation management policies on the other.A report in 1998 into the Commercial Utilisation of Australia Native Wildlife concluded “that it is a legitimate activity of the Federal Government to support an export industry based on the commercial harvesting of kangaroos, which is being prejudiced overseas by public campaigns based on false information.”
Conservation benefit from harvesting kangaroos: status report at the start of a new millennium: A paper to stimulate discussion and research
This paper explores the view that the best way to reduce grazing pressure in Australia’s rangelands is by reducing sheep through increasing the value of kangaroo production. This would harness economic incentives in the service of ecological sustainability and rangeland rehabilitation and achieve conservation goals through the sustainable use of wildlife. Grigg advocates a strong marketing effort and provides some suggestions about the benefits of kangaroo harvesting which could feature in a marketing campaign.
NSW Government has prepared this handbook to help kangaroo harvesters meet NSW requirements for the commercial kangaroo industry. It contains general information about the commercial kangaroo industry and serves as a guide for applying for licences and tags, harvesting kangaroos in filling in returns.
Provided by the Australian Government, this outlines the basics of kangaroo harvesting in Australia and the roles and responsibilities of state and federal governments.
(Pople, Cairns, & Menke, Monitoring Kangaroo Populations in Southeastern New South Wales, 2003)
This report examines the feasibility of monitoring kangaroo populations in the southeast of NSW, in the 5 x (former RLPB) areas of Braidwood, Cooma, Goulburn, Gundagai and Yass. At that time commercial harvesting didn’t take place in those areas but landholders were culling significant numbers of kangaroos using pest destruction licences. This was felt to be an inefficient means of pest control and wasteful, as well as potentially having less humane outcomes for the kangaroos. This report was undertaken to see whether monitoring was feasible in these areas. Population monitoring is a state and federal government requirement for commercial harvesting to ensure conservation of the species.Interesting quote: “In wildlife management, the appropriate survey frequency and precision has generally been considered with aim of detecting trends….In kangaroo management, harvest regulation is primarily through quotas that are set as proportions of absolute estimates of population size. Trends are of secondary importance.”Talks about risks of both over and UNDER harvesting. P19 “It would seem logical to issue commercial harvesting tags and licences and SLL licences from the same office.”!
(Lundie-Jenkins, Hoolihan, & Maag, 1999)
Since the introduction of quotas in 1975, systems have been in place to monitor population trends, the size and distribution of both the commercial and non-commercial harvest, non-harvest mortality and reports of damage to primary production. This 1999 paper investigates the different survey techniques being used at that time. Whether the prime goal of management is conservation, sustained-yield harvesting or pest control, management decisions must be guided by the best available monitoring techniques.
(Pople A. R., Repeatability of aerial surveys, 1999)
Broad-scale aerial surveys of kangaroos using fixed-wing aircraft service three purposes. (1) estimates of kangaroo abundance from which sustainable harvest quotas can be determined. (2) Describe kangaroo distribution and (3) Identifying trends in the kangaroo population over time. In order to provide scientifically robust population estimates, aerial survey methods mot provide density estimates that are a constant proportion of the true population density and are therefore repeatable. This work undertook to compare surveys from fixed wing and helicopters to confirm bias and improve correction factors and accuracy of estimates.
(Pert & Norton, 2010)
The potential use of existing radiometric data sets, previously collected for prospecting purposes, has very rarely been used as a variable predictor in wildlife habitat modelling. The utility of radiometric data for predicting vegetation community patterns and wildlife habitat was investigated in the Australian arid zone using the Burt Plain bioregion as a case study.
The effect of non-sex biased shooting on some population characteristics of the Eastern Grey Kangaroo in the Murrurundi area, New South Wales
Data obtained from two surveys conducted in the winters of 1986 and 1987 show that, for the study area centred on the town of Murrurundi in the upper Hunter Valley of NSW, non-sex biased commercial shooting of the Eastern Grey Kangaroo did not greatly alter population age and sex structure. It was found, however, that shooting in general (whether commercial or non-commercial) decreased the presence of large pouch young, thus delaying the reproductive activity of a populations compared to those protected from shooting.
Subsidized Commercial Harvesting for cost-effective wildlife management in urban areas: a case study with kangaroo sharpshooting
(Mawson, O’Hampton, & Dooley, 2016)
The management of overabundant urban fauna is a contentious issue worldwide, particularly
for populations of white-tailed deer (Odocoileus virginianus) in North America and kangaroos (Macropus spp.) in Australia. To be successful, management programs in such settings must be cost-effective, humane, and publicly acceptable. Here, we describe the management of a fenced, urban population of western grey kangaroos (M. fuliginosus) in southwestern Australia, with an estimated population density of 189 kangaroos/ km2. After a period of >12 months of solicited public involvement by key stakeholder groups, a licensed professional shooting team, observing a national code of practice, conducted night-time sharpshooting. Over an 11-month period in 2006–2007, 1,009 kangaroos were shot in 43 shooting nights, a mean (_SE) culling rate of 23_3 kangaroos/night or harvest rate of 12_2 kangaroos/hr. Inspectors under the relevant Western Australian legislation functioned as animal welfare observers to ensure that the methods employed for the culling program met the national code of practice and that all license conditions were met. No accidents or injuries occurred during the program. The program produced 17 kg/kangaroo of harvestable meat and biological samples for several research projects. The operational costs of the project were very low, at AU$36/ kangaroo, with payments largely limited to incentives paid to commercial harvesters and management staff monitoring public safety and animal welfare. This case study is an example of a publicly acceptable, cost-effective, humane, and lethal urban wildlife control operation. It demonstrates that public acceptance of a cull of wildlife can be forthcoming with appropriate prior consultation and high professional standards.
This paper investigates the accuracy, bias and consistency of the methods for estimating kangaroo populations and the need to review correction factors.
(Marques, Buckland, Bispo, & Howland, 2012)
Distance sampling is extensively used for estimating animal density or abundance. Conventional methods assume that location of line or point transects is random with respect to the animal population, yet transects are often placed along linear features such as roads, rivers or shorelines that do not randomly sample the study region, resulting in biased estimates of abundance. If it is possible to collect additional data that allow an animal density gradient with respect to the transects to be modelled, we show how to extend the conventional distance sampling likelihood to give asymptotically unbiased estimates of density for the covered area. We illustrate the proposed methods using data for a kangaroo population surveyed by line transects laid along tracks, for which the true density is known from an independent source, and the density gradient with respect to the tracks is estimated from a sample of GPS collared animals. For this example, density of animals increases with distance from the tracks, so that detection probability is overestimated and density underestimated if the non-random location of transects is ignored. When we account for the density gradient, there is no evidence of bias in the abundance estimate. We end with a list of practical recommendations to investigators conducting distance sampling surveys where density gradients could be an issue.
(Lundie-Jenkins, Pople, & Hoolihan)
Broad-scale aerial surveys of kangaroo populations have been conducted regularly over vast areas of the rangelands since the 1970s to monitor population trends and to determine harvest quotas. Whilst there is obvious worth in monitoring kangaroos in their own right they may also be useful as surrogates for other elements of the biodiversity and as indicators of environmental change.
Fertility control in female eastern grey kangaroos using the GnRH agonist deslorelin.2. Effects on behaviour
(Woodward, Herberstein, & Herbert, 2006)
In recent years fertility control has been proposed as an ethically acceptable alternative to lethal control techniques when managing overabundant kangaroo populations. A promising non-steroidal, non-immunological approach to contraception in female kangaroos involves the use of slow-release implants containing the gonadotrophin-releasing hormone (GnRH) agonist deslorelin. The practicality of using deslorelin implants as a management option is dependant on its effective inhibition of reproduction without negative physical or behavioural side-effects. This study investigated the behavioural effects of deslorelin implants in female eastern grey kangaroos.
(Pople A. R., 2004)
In wildlife management, the program of monitoring will depend on the management objective. If the objective is damage mitigation, then ideally it is damage that should be monitored. Alternatively, population size (N) can be used as a surrogate for damage, but the relationship between N and damage obviously needs to be known. If the management objective is a sustainable harvest, then the system of monitoring will depend on the harvesting strategy. In general, the harvest strategy in all states has been to offer a quota that is a constant proportion of population size. This strategy has a number of advantages over alternative strategies, including a low risk of over- or underharvest in a stochastic environment, simplicity, robustness to bias in population estimates and allowing harvest policy to be proactive rather than reactive. However, the strategy requires an estimate of absolute population size that needs to be made regularly for a fluctuating population. Trends in population size and in various harvest statistics, while of interest, are secondary. This explains the large research effort in further developing accurate estimation methods for kangaroo populations. Direct monitoring on a large scale is costly. Aerial surveys are conducted annually at best, and precision of population estimates declines with the area over which estimates are made. Management at a fine scale (temporal or spatial) therefore requires other monitoring tools. Indirect monitoring through harvest statistics and habitat models, which include rainfall or a greenness index from satellite imagery, may prove useful.
Fertility control in female eastern grey kangaroos using the GnRH agonist deslorelin. 2. Effects on behaviour
(Woodward, Herberstein, & Herbert, 2006)
Eastern grey kangaroos are widespread on the east coast of Australia and frequently reach high densities in reserves and parkland near urban areas. Management of these populations is highly contentious and non-lethal fertility-control technologies are sought as an alternative option to manage population size. This study evaluated the potential of slow-release gonadotrophin-releasing hormone agonist (deslorelin) implants to inhibit reproduction in female kangaroos. Deslorelin treatment effectively inhibited reproduction in adult females for periods of 559 ± 111 days (n = 6) and 651 ± 21 days (n = 5) after administration of one or two 10-mg implants respectively. Animals treated with the lower dosage tended to resume breeding earlier than those that received a total of 20 mg of deslorelin (minimum duration of 18 months). Deslorelin treatment had no effect on blastocyst reactivation in a single treated female and repeat treatment had no negative side-effects. This study has demonstrated that slow-release deslorelin implants can successfully inhibit reproduction for extended periods in the female eastern grey kangaroos. This approach may have potential application in reproductive management of problem kangaroo populations.