||This article is written like a personal reflection or opinion essay rather than an encyclopedic description of the subject. (November 2012)|
The kangaroo industry is based on the harvesting of the large species of kangaroos, which are abundant and are sustainably harvested in Australia under strict government control. Many professional ecologists support this industry on the basis that it delivers significant environmental benefits. Many argue kangaroos, which are native to Australia, are a more environmentally friendly livestock option than introduced sheep and cattle.
- 1 Products
- 2 Kangaroo populations
- 3 The harvest quota setting process
- 4 Licensing controls over kangaroo harvesters
- 5 Environmental effects of using kangaroos
- 6 Environmental impacts of not using kangaroos
- 7 Animal welfare
- 8 Kangaroo use and a new ecological model
- 9 Kangaroos and global warming
- 10 References
Kangaroo meat is consumed in Australia and available in some Australian supermarkets. It is also exported to over 55 countries. Kangaroo leather is recognised as the strongest lightweight leather throughout the world and extensively used in first class sporting shoes and gloves.
Over 99% of the commercial kangaroo harvest occurs in the arid grazing rangelands. The populations of kangaroos in these areas are estimated every year in each State by well-developed aerial survey techniques. These are sparsely timbered, [savannah] type ecosystems; hence, it is possible to fly over them and count the large animals, such as kangaroos, seen. Using either low-flying fixed-wing aircraft or helicopters, flying at heights of two to 300 meters, the National Parks authorities count the numbers of kangaroos seen over fixed transects. Thirty years of such monitoring have allowed them to develop sophisticated and accurate techniques of extrapolating out to total population numbers. Kangaroos are one of only a very few species (including humans) which have an annual census of their populations.
It is widely accepted that within the rangelands kangaroos are now more common than prior to European settlement. This situation has arisen due to the increased food and water supply generated by the activities of the sheep and cattle industry. Prior to European settlement, these areas had very few places of surface water from which kangaroos could drink. The pastoral industry has tapped into below-ground water supplies to the point where now very few points in the rangelands are further than 3 km from a permanent water source and no point is further than 10 km.
The harvest quota setting process
For any kangaroo species to be harvested, the State's National Parks authority must have a detailed management plan approved by the federal conservation department. These plans must detail the population monitoring and quota-setting controls and the controls over the take, and they must be renewed every five years.
Each year after the population estimate is obtained, each management plan will set a maximum allowable take (quota) of between 10 and 20% of total population. The populations fluctuate depending on seasonal conditions; during droughts they can decline, or they can increase dramatically during good seasons. The State's authority will then issue individually and sequentially numbered plastic lockable tags. These tags are designed to ensure, once properly applied, any tampering with them will be perfectly obvious.
Each kangaroo taken by licensed harvesters must have such a tag fixed to it and the harvester and processor must report back to the authorities on a monthly basis the details of the exact number of the tags they have used, where the tags were used, and what species, sex and weight of animal to which they were attached. The authority monitors the release and use of tags to ensure the harvest in any one area does not exceed the quota.
The complexity and detail of the controls in the management plans can be indicated by a brief examination of the NSW plan. It divides the State into 15 different zones, 14 in which commercial kangaroo harvesting is allowed and one comprising over one-third of the State in which no harvesting can take place. The population is estimated in each individual zone and a harvest quota allocated to it. An appropriate number of tags are then issued to the conservation authority managers in each zone, and these can only be obtained by kangaroo harvesters on two days of each month. The harvester must use and submit reports for all tags issued before more can be obtained, and the issue of tags by zone is closely monitored. As soon as the harvest in any one zone approaches the quota, it is closed to commercial activity for the rest of the year.
Licensing controls over kangaroo harvesters
To purchase the tags issued by the authorities, kangaroo harvesters must be licensed as such. To do so, they must undergo training delivered by government-accredited agencies and approved by the Australian Tertiary and Further Education agency in the appropriate State. This training covers the regulatory controls and compliance requirements, the animal welfare controls, and the hygiene controls to which each harvester must adhere. They must then pass assessment in their knowledge and practices relating to these controls by two separate government departments. This will include assessment of their competency with their firearms. Only then will they be able to obtain the required licenses from the two authorities concerned.
The kangaroo harvesters' licenses are conditional on adherence to the guidelines laid out in the federal ‘Code of Practice for the Humane Shooting of Kangaroos’. This specifies the minimum high-caliber firearms which can be used, and requires all animals to be head-shot, and documents procedures for the humane dispatch of any pouch young.
Any kangaroo or kangaroo product accepted by processors, be it for meat or skins, must have an approved tag applied to it and be supplied by a licensed harvester. Each processor must report on a monthly basis to the State authority the numbers of kangaroos purchased, from whom, and the relevant tags numbers.
Environmental effects of using kangaroos
The kangaroo management plans have been operating under strict and intensive supervision for almost 30 years. Over this period, the average harvest per year has been in excess of 2 million animals.
Despite long-term harvests in excess of 2 million animals per year, the kangaroo population has consistently increased. Even following the worst drought on record (2005–07), numbers in 2008 are still at what could be considered historically typical levels. Their current population of 25 million is only marginally lower than the 25-year average of 26.7 million (which is skewed by the very high levels reached during a run of highly favorable years in the late 1990s).
A project conducted by NSW Department of Agriculture, which employed extensive field study and highly sophisticated computer modeling techniques, has cast light on why kangaroo populations are so resilient to harvesting. The project examined harvester activity and modeled it in response to terrain and prices paid for kangaroos harvested. It demonstrated, in the areas investigated and at current prices, 20-40% of any one property will rarely be visited by a kangaroo harvester because the terrain is too rough or other limitations make it not economic to do so. These areas then become ‘refugia’, areas in which the resident kangaroo population is never harvested and from which the population expands to repopulate areas which are harvested.
The authors conclude:
“Models presented here suggest that kangaroo populations may be more resilient to harvesting than we had previously thought”.
Effects on the species
The argument is often mooted that kangaroo harvesting selects the largest animals and will therefore affect the genetic fitness of the species. The scientific data strongly refute this argument. Four separate reports have recently provided considerable evidence to discount these claims.
- An examination of the question submitted to the NSW National Parks and Wildlife Service in 2001 concluded:
- “Currently, there is no evidence of real or potential genetic ‘deterioration’ due to harvesting, nor any reason to suspect it. Indeed, indications are that kangaroo numbers would have to be reduced to extremely low levels for genetic impacts to become important and by then other impacts, such as demographic disruption, would be overridingly important”.
- An extensive report into factors affecting genetic makeup in kangaroos by the University of Queensland concluded:
- “The effects of the commercial harvest are therefore unlikely to produce genetic changes in the population. First, the heritability of the characters in question is low. Second, the selection differential is low because differences in fitness between younger and older adult males is small, older males do not appear to monopolise matings, only a small proportion of older males are selected against (so most animals are in the selected group), and only a small proportion of the population is harvested.”
- A study of Queensland kangaroo populations harvested at rates of 0 to 30% has shown no differences in the genetic diversity of the various populations. That is, intensively harvested populations show no reductions in genetic diversity compared to unharvested ones. This study also cites information showing virtual uniformity of genetic codes across widely dispersed kangaroo populations, suggesting the extensive harvesting to date has had no effect on the species.
- A study conducted by the NSW Department of Agriculture has applied extremely sophisticated computer modeling techniques to kangaroo population’s dynamics. It has demonstrated, even after several hundred years of intensive harvesting, there would be no impact on the genetic makeup of the population, a large cause of this being there are always areas of rugged terrain in which kangaroos are never harvested (refugia) and migration of animals and their genetic material out of these areas offsets any selection which may occur through harvesting.
Environmental impacts of not using kangaroos
Several trials have indicated uncontrolled kangaroo numbers present a risk to plant biodiversity. Kangaroos can not be commercially harvested in National Parks; as a result, their numbers often rise to excessive levels which sometimes require culling programs to be used. In biodiversity monitoring done following a cull at Hattah-Kulkyne National Park in Victoria, increased abundance of 20 rare or threatened plant species was recorded in areas where kangaroo were culled compared with control areas (Sluiter et al. 1997).
All kangaroos taken for commercial use are harvested by professional shooters. State and federal government controls ensure that no kangaroo can enter the commercial industry unless it has been taken by a licensed kangaroo harvester who has passed an accredited training course, which includes training in the animal welfare aspects of kangaroo harvesting. In addition, anyone wishing to harvest kangaroos for human consumption must undergo assessment of their accuracy with their firearms. The accreditation and competency assessment are controlled by state government regulations in each State.
Kangaroo use and a new ecological model
To date agricultural development in Australia has largely been based on modified European systems, using European animals. In recent decades this Eurocentric view has come under considerable academic question. A ground swell of opinion is developing that Australians should develop management systems adapted to the specific environmental conditions, not impose systems adapted to Europe. Under this philosophy use of free ranging populations of native animals adapted to the environment makes environmental sense.
To this end the University of New South Wales has implemented a major new project aimed at encouraging the development of farm enterprises based on using native plants and animals and specifically kangaroos. The project intends to monitor the environment benefits that accrue from doing so.
Kangaroos and global warming
Kangaroos emit small amounts of methane compared to domestic livestock. Cattle and sheep do so in large volumes, and methane is 21 times worse than carbon dioxide as a global warming gas. The beef industry alone is estimated to account for 11% of Australia’s carbon emissions. Many ecologists are now suggesting changing production systems to grow kangaroos for meat rather than cattle or sheep can help reduce Australia’s greenhouse gas emissions.
- Conserving the Kangaroo
- The Kangaroo Industry - Ecologists and Conservationists
- FATE Program
- Enhancing the Unique Properties of Kangaroo Leather
- Commercial kangaroo harvesting fact sheet
- Kangaroo Population Estimates
- Australian Agricultural Statistics
- Landsburg, J (1999). The effects of artificial sources of water on rangeland biodiversity. CSIRO Div. Wildlife and Ecology, Biodiversity Technical Paper no 3
- Kangaroo Management Program
- National codes of practice (commercial and non-commercial) for the humane shooting of kangaroos and wallabies
- Kangaroo Management Options in the Murray-Darling Basin. 2004. Ron Hacker, Steve McLeod, John Druhan, Brigitte Tenhumberg & Udai Pradhan. Murray-Darling Basin Commission and NSW Agriculture. ISBN 1-876830-70-0 MDBC Publication number: 02/04
- Situation Analysis Report: Current State of Scientific Knowledge on Kangaroos in the Environment, Including Ecological and Environmental Impact and Effect of Culling.
- Kangaroo Genetics, Impacts of Harvesting
- Pople 1996
- Sluiter, I., Allen, G., Morgan, D. and Walker, I. (1997) Vegetation responses to stratified kangaroo grazing at Hattah-Kulkyne National Park, 1992-96. Dept. Natural Resource, Melb
- FATE and kangaroos
- Native Wildlife on Rangelands to Minimize Methane and Produce Lower-emission Meat: Kangaroos Versus Livestock