Tag Archives: Sheila Newman

ACT Roo killings: Who profits? Behind the Earless Dragon mask

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Human Population growth impacts on wildlife

The endangered Earless Dragon is being used to justify killing thousands of Eastern Gray kangaroos in Belconnen and Majura, but the motive is really developers’ profit. As grasslands are turned into building sites, as human population growth is encouraged.. Kangaroos are in the way, as is democracy, so both are being buried.

When an Earless Dragon is like a smoking gun we should ask who fired the gun.

Did the ACT government organize the mass killing of thousands of Eastern Grey kangaroos in Belconnen and Majura, near Canberra, in a sudden uncharacteristic and galvanic effort to save the endangered Earless Dragon?

Thousands of Eastern Grey kangaroos have recently been shot and bulldozed into pits in Belconnen and Majura, [1] Australian Capital Territory (ACT), in fatal massive round-ups which have not been seen since early last century. In a torrent of official reports and statements, scientists and politicians have fingered the Eastern Grey Kangaroo for overgrazing rare grasslands and thus threatening their other inhabitants, notably the endangered Earless Dragon.

Who would have thought that the little Earless Dragon had such powerful friends in government, planning, universities and business – even the Canberra International Airport? [2] The Grasslands Earless Dragon doesn’t pay taxes and doesn’t directly contribute to political fundraisers, but it is often associated with grants and development programs these days.

Were these culls really for the benefit of the Earless Dragon? Or was the Earless Dragon only an excuse for this macropod massacre, in which case, what was the real motive?

Although these planned culls aroused public ire and many questions, formal responses were highly selective. Many questions about the Belconnen cull went unanswered and remain unanswered. When the Majura cull came up on the agenda, the same angry questions received the same infuriating non-responses.

2008bntsroobodiesthrownintopitinmajura

(image: https://wildlifecarersgroup.wordpress.com/category/kangaroo-issues/)


The public and the kangaroos deserve much better.

It was so difficult to make sense of what was happening. Could the whole thing actually be as cruel and stupid as the kangaroo-cull protesters claimed? Or were the protesters really childish people who could not accept the obvious need to put some animals which had ‘bred like rabbits’ out of their misery?

After all, the Royal Society for the Protection of Animals (RSPCA) had given its seal of approval. That meant it must be okay, right? Right?

My own preoccupation over the months intervening between the Belconnen and the Majura kills had been to ascertain what population theory was used to arrive at the diagnosis of overpopulation or to assert that there should be only one kangaroo per hectare. My search failed. This question has now become one of whether there was any population theory at all.

A theory of how kangaroo populations behave is necessary for any outsider to be able to test the validity of the judgement that the Majura Roos or the Belconnen Roos or any other roos were overpopulating and needed ‘culling’. Saying that there should be one per hectare or that they may die of starvation are remarks which, on their own, do not justify culls.

I was amazed that official reports did not begin with a description of how kangaroo populations were thought to operate, how this theory had been tested and the populations measured. In an effort to find out if any real theory and application had taken place, I attempted to contact officials and scientists involved in kangaroo management programs of one sort or another. No population theory of any kind, whether or not demonstrating lemming-like multiplication tendencies in kangaroos, has yet surfaced as a reasonable basis of the culling of the Belconnen or Majura roos.

What did emerge was that there was an overtly declared perception of conflict between human activities and the presence of kangaroos in grazing and a less overtly acknowledged conflict between land-use intensification in urban development, such as roads and new suburbs, accompanying the promotion of radical human population growth policies in the ACT. (See, for instance, this description of planned expansion and intensification in the area.)

shameful-pit

Dr Fletcher’s thesis oddly at odds with Canberra culls

One scientist who was closely associated with the Belconnen cull and the Majura cull, was Don Fletcher. Fletcher is the Senior Ecologist in Research and Monitoring in Parks, Conservation and Lands, Department of Territory and Municipal Services, ACT. His involvement in the Belconnen Roo cull seems to have been officially limited to capturing then releasing female survivors after inserting contraceptives in them. He was one of the writers of the public consultation document leading up to the Majura cull.

He defended these culls and has defended the assessments leading up to the Majura culls in a public consultation document. Yet his own thesis on the “Population Dynamics of Eastern Grey Kangaroos in Temperate Grasslands,” (pdf 4.27mb) seemed to discredit claims at the basis of these culls, which were too high population density and a need to manage it down to one kangaroo per hectare. For instance, he wrote on page 237 of his study that :

“The study did not provide evidence that high densities of kangaroos reduce groundcover to the levels where erosion can accelerate. Unmanaged kangaroo populations did not necessarily result in low levels of ground cover. Groundcover had a positive but not significant relationship to kangaroo density, with the highest cover at the wettest site where kangaroo density was highest. Weather has an important influence on groundcover.” [3]

He also wrote that some of the populations he was studying were at the highest density recorded. They ranged between 4.5 and 5.1 kangaroos per hectare. The density in the studies below was expressed in square kilometers. To get density per hectare, divide by 100. [4] Fletcher wrote:

“The kangaroo density estimates reported in Chapter 7 for the three study sites (mean eastern grey kangaroo densities of 450, 480 and 510 km2) are the highest kangaroo densities reported. For comparison, the maximum density of combined red kangaroos and western grey kangaroos in the Kinchega study was less than 56 km2 (Bayliss 1987) and the density of eastern grey kangaroos at Wallaby Creek (Southwell 1987b) was 41 to 50 km2. The next highest kangaroo density outside the vicinity of my study sites appears to be that of Coulson et al. (1999a) for eastern grey kangaroos at Yan Yean Reservoir near Melbourne, which was 220 km2.”

Coulson’s study of kangaroos at 2.2 per ha was published in 1999 as Coulson G, Alviano P, Ramp P, Way S “The kangaroos of Yan Yean: history of a problem population”. [5] Graham Coulson’s Yan Yean article is frequently cited by kangaroo population students and he seems to be thought of as the originator of the “one kangaroo per kilometer” ‘rule’.

I did contact Dr Fletcher by email, and he was initially quite friendly, but when I attempted to ask him questions about his thesis responses to my emails ceased, even though I re-sent the emails.
For every assertion a contradictory one remains unanswered

The ACT Kangaroo Advisory Committee Report No.1 (issued prior to the Majura cull) reported conflict between kangaroos and the rural community which uses 23% of the ACT.

“A key issue for rural lessees is the conflict between kangaroo grazing and pasture and fodder crop production.”
(ACT Kangaroo Advisory Committee Report No.1. )

It stated as fact anecdotal reports that kangaroo populations ballooned due to man-made pasture improvements.

“There is general consensus that, in other parts of Australia at least, land clearing and swamp drainage to extend areas for introduced pasture, together with the increase in the number of farm dams has improved habitat for Eastern Grey Kangaroos and some other macropods, leading to increased numbers.”

But these anecdotal reports are very selective and easily countered by others, for instance in Dr John Auty’s comprehensive review of original documents forming the history of kangaroo populations from the time of European settlement in Australia. See “Red Plague Grey Plague – Kangaroo [numbers] myths and legends”

Other ACT researchers have also questioned the logistical principle of blaming kangaroos for human pressures on the environment, i.e. why blame kangaroos when we know that the damage is outstandingly done by sheep and cattle? In the Olsen and Low report case cited below the researchers are talking about farming, but they could just as much be talking about new suburbs, i.e. why blame kangaroos when the damage is obviously being done by human population growth, accompanying infrastructure and housing development (roads and suburbs), and human activities (driving cars, growing lawns, shopping, expansion of production, etc.)?

The discontinuation of damage mitigation as grounds for harvesting is in many ways a more honest approach to kangaroo management given that damage is difficult to monitor, predict and even to prove empirically to be an issue. It also removes the implication that kangaroos are pests.

However, some landholders still perceive damage mitigation to be the main reason for harvesting and continue to call for greater quotas, mainly during the recent years of low rainfall. Arguably, this is a socio-economic problem rather than an ecological one. Certainly, the issue of land degradation will never be redressed by simple reduction in kangaroo numbers when there is no concomitant control of sheep and other introduced herbivore grazing impacts.” Olsen and Low Report. [6]

Is the real conflict over the grasslands between developers and kangaroos rather than kangaroos and earless dragons?

Fletcher, in his thesis, describes Kangaroo density in the ACT as having “increased more rapidly from 1996 to 2000 after sheep and cattle grazing had ended.” [7] Sheep and cattle had been allowed to graze in the threatened grasslands. In some cases they have even been returned to the areas where kangaroos have been ‘euthanazed’ to protect those fragile grasslands.

The question asked here should not be whether the kangaroo density increased to take up pasture vacated by sheep and or cattle. The real question should be: Did such a reduction in sheep and cattle grazing then bring the unfortunate kangaroos into conflict with urban developers over the rezoning of agricultural land for rural use?

In fact, if we drop the non-issue of kangaroo numbers, the relevance of developer-ambition conflicting with retaining grasslands for any indigenous animals becomes obvious.

Kangaroos graze there, which is obviously better than sheep and cattle grazing there, but property developers want to raise far more lucrative crops of humans there by building roads and houses where kangaroos now graze, along with earless dragons.

Unfortunately the government is encouraging developers. Maxine Cooper, Commissioner for Sustainability, in her report on ACT Lowland Native Grassland Investigation, says that the “ACT is fortunate in being in a strong position to be able to advance the protection of lowland native grassland, in particular Natural Temperate Grassland communities and the species it supports,” … BUT… [she adds]:

“Protecting lowland native grassland from development is also a challenge as these areas, being generally flat to gently undulating with no trees, are often prime potential development sites. Much of Canberra’s development is on lands that were once lowland native grassland.” Maxine Cooper Report, p. v.

“Development that potentially affects lowland native grassland is either underway or planned for the ACT (see Section 5). This development has the potential to sever corridor and connectivity between grasslands and woodlands and/or other adjacent habitats. Many of the recommendations presented in this report reinforce the importance of connectivity.” Maxine Cooper Report, pp 74-75,

Now most of the competition with kangaroos is from property development. Stimulating property development is government policy and the means of stimulus is a policy to encourage interstate immigration and natural increase through baby bonuses.

This government decision to stimulate human population growth in the ACT and to expand development in the ACT causes pressure on the local kangaroo population and the population of the Earless Dragon in the ACT.

Grave failure of public education and democracy

The commercially-based decisions about human population policy which cause these pressures, however, are kept entirely out of official calculations, negotiations, and rationales pertaining to kangaroo culls and definitions of kangaroo overpopulation in Belconnen and Majura, ACT. This omission means that the public do not have the information to hold the government responsible where it should be held responsible, nor to question the costs of its policies. This represents a grave failure of public education and democracy.

Oddly, Maxine Cooper, in her “Report on ACT Lowland Native Grassland Investigation,” 12 March 2009, mentions and notes the threat to the grasslands from development, yet she does not factor this logically into the reasonableness of blaming and killing kangaroos.

Instead, she uncritically accepts the illogical explanations which she is provided with about kangaroos. She even provides further faulty measures of kangaroo population densities by rate of car-kangaroo collisions.

“The 2007–08 State of the Environment report states that motor vehicle accidents involving kangaroos has increased by 38% (from 563 in 2005–06 to 777 in 2006–07). Rangers have advised that they now attend more than 1,000 roadside kangaroo incidents per year in Canberra.” [8]

Although Maxine is aware that the building of roads and suburbs is impacting the grasslands, she does not stop to think that these are also impacting the kangaroos through an increasing rate of driving them out of their habitats and onto the roads to make way for houses.

If, however, commercial development pressure were properly assessed, then its role as the primary population impact on the grasslands and the cause of ACT policies to depopulate kangaroos would become obvious and the government would no longer be able to deflect criticism of overdevelopment and cruelty to kangaroos.

Who profits? When an Earless Dragon is like a smoking gun we should ask who fired the gun.

What of the Earless Dragon in all this? Small and scarce, it is not hard to imagine it fitting into a developer’s pocket-size native-style garden. You could even imagine thirty-something refugees from housing prices in Sydney and Singapore cultivating it in garden pots in new high-rises. Imagine is the key, since who would check up?

Pardon me for being skeptical, but the high profile of the Earless Dragon makes me think of advice to writers about mentioning loaded guns in detective stories. If there is a gun it is there to shoot a victim for a motive. The huge importance suddenly given to the humble Earless Dragon bespeaks a greater purpose than the self-evident worth of its own preservation.
Cherchez le maccabe. [Find the cadaver.] The Dragon is the weapon to get rid of the much-loved kangaroos. There can be no argument there, for we hear little else but how the kangaroos are threatening this little animal. Once the kangaroos are gone, the tiny Dragon’s profile will almost certainly sink back to the level which escapes most humans’ notice, unreported by the mainstream press.

Let us ask the ever-useful sociological question here. Who benefits? Developers and their friends do.

Let justice be done

You wouldn’t think it from listening to politicians, but I have it from a reliable source that, in the ACT, the biggest source of public complaint is cruelty to animals. People should realize that they are not alone in their horror at the cruelty entailed by all this unwanted (except by its few focused beneficiaries) and costly population growth and development. The Earless Dragon has been deployed with the effect of sowing paralysing confusion among nature groups by implying an ungenerous bias for furry kangaroos against ugly dragons.

”To save the beauty, or the beast; that is the question”

Eastern grey kangaroos are among the most appealing of mammals (Figure 12), while Ginninderra Lepidium, Grassland Earless Dragons, Coorooboorama Raspy Crickets (Figure 4), Striped legless Lizards, Perunga Grasshoppers (Figure5), Golden Sun Moths (Figure5), and other grassland-dependent plants and animals, are all ugly. Well that may be one opinion, but if so, it is irrelevant. Governments are legally and morally obliged to protect each species. Beauty is not a consideration.” ”A Pictorial Guide to the Kangaroo Culling Issue, Dept of Territorial and Municipal Services, ACT Government” [ 9]

This has the hallmarks of a straw man argument.

Let the community be heard as it rises to save the grasslands and return them to their rightful management by kangaroos and Earless Dragons. Let due opprobrium be publicly dealt the Growth Lobby by exposing its greed and cowardice in orchestrating the cold-blooded execution of thousands of living, breathing, social creatures for economic and ecological crimes they could never have committed, merely to defend its exceedingly narrow and debt-ridden interests. Let us sheet home to the Growth Lobby and its minions in government the depravity with which they attempt to corrupt our wider society. We are not cruel or injust. We do not support cruelty and injustice.

It seems amazing that Maxine Cooper can support a kangaroo cull when she also writes that the Majura Valley grassland is “arguably one of the largest areas of Natural Temperate Grassland remaining in southeast Australia” but that it has no long-term planning protection and there is no commitment for any, and that to protect it by defining it as a reserve would

“[…]constrain future development options, for example, the potential Canberra International Airport northern link road and the potential east-west Kowen road [… and] would also ensure that the Natural Temperate Grassland, the Grassland Earless Dragon and other threatened species are not adversely affected through incremental developments, as would be the case if the potential Canberra International Airport northern link road and the potential east-west Kowen road were to be progressed according to existing concept plans.” [10]

In other words, Maxine Cooper is aware that plans for several new roads and urban expansion are planned for the Majura grasslands and sees that it will be necessary to curb this development to protect the grasslands. [11]

Some of Cooper’s other recommendations (apart from those which promote the culling of kangaroos on illogical grounds) are good. I provide these in the appendix to this article.

Earless Dragon scarcity previously coincided with kangaroo scarcity in ACT

Don Fletcher, in “Population Dynamics of Eastern Grey Kangaroos in Temperate Grasslands,” describes how, in the 1940s and 1950s kangaroos actually became rare in the ACT due to competition by European grazing stock. Even when these stock were removed, they remained rare for some time. Salt blocks were put out in the 1960s to attract kangaroos to the Tidbinbilla Fauna Reserve, where in 1963 employees went for three months without seeing one.) [12]

Oddly, at the same time as kangaroos were banished from the ACT, the Earless Dragon also became scarce. It couldn’t have been because of too many kangaroos.

“The Grassland Earless Dragon was very common in the ACT up to the 1930s but there are now very few left. This is mainly because there are so few areas of its native grassland habitat remaining. There are now only two main populations known in the ACT; and there is one near Cooma in NSW.” Source: The ACT Conservation Council, http://www.consact.org.au/index.php?option=com_content&task=view&id=47&Itemid=34#GED
[13 ]

Note that the Earless Dragon was also found in 2001 in Mount Tyson on Queensland’s Darling Downs. [14]
APPENDIX: Maxine Cooper, in her “Report on ACT Lowland Native Grassland Investigation,” 12 March 2009

Recommendation 23: Plan a Majura Valley Reserve to protect Natural Temperate Grassland and its supporting species, particularly the Grassland Earless Dragon, by defining the boundaries of this proposed reserve in the near future.”

“Findings that informed Recommendation 27
During the investigation, the Commissioner’s Office found it difficult to identify the location of lowland native grassland sites relative to planning zones that guide land use. To help the community and developers gain information on grassland sites relative to planning zones it is recommended that a map of the location of lowland native grassland sites relative to planning zones be published.

Recommendation 27: Publish a map that shows the location of lowland native grassland sites relative to planning zones. This should be readily available through the ACT Planning and Land Authority and the Department of Territory and Municipal Services.” Source: Maxine Cooper, Commissioner for Sustainability and the Environment, “Report on ACT Lowland Native Grassland Investigation,” 12 March 2009, pp 73-74

“In terms of biodiversity conservation, the ideal approach is to establish a series of conservation reserves (which may include voluntary schemes) that are of sufficient size and biodiversity to maintain a full range of ecological communities (and hence species) on a long-term basis. It is also desirable for such reserves to be located to enable connectivity for animal movement and other interactions between them. 125
The natural connections between grasslands and adjoining woodlands have mostly been severed, but should be retained where they still exist.

Important grassland sites for connectivity between woodland and grassland are at:

• Mount Ainslie Nature Reserve and Campbell Park (MA05)
• ‘Callum Brae’ (JE02)
• Jerrabomberra West Reserve (JE03) and woodland to the west
• Gungaderra Nature Reserve (GU02) and Gungahlin Hill
• Aranda Bushland and Caswell Drive (BE10)
• Majura Valley at the Majura Training Area (MA01).

Important grassland sites for connectivity between grasslands are at:

• Campbell Park (MA05) and Majura West (MA06)
• adjacent grassland on either side of the ACT and New South Wales border via Harman Bonshaw North (JE06) and Harman Bonshaw South (JE07), Jerrabomberra East Reserve (JE05), Woods Lane (JE06), and Queanbeyan Nature Reserve (Letchworth, New SouthWales)
• adjacent grassland between the Canberra International Airport (MA03) the Majura
Training Area (MA01) and ‘Malcolm Vale’ (MA04). Pp. 74-75

NOTES

[1] “Majura roo cull targets 6000, Canberra Times, 2 May 2009, http://www.canberratimes.com.au/news/local/news/general/majuraroo-cull-targets-6000/1502384.aspx and
Victor Violante, “Roo cull under way: 2000 shot”, Canberra Times, 9/05/2009,
“About 2000 eastern grey kangaroos at the Department of Defence’s Majura Training Area have been culled this week, with a further 4000 expected to be shot. Defence confirmed yesterday that culling had begun on Tuesday and contractors doing the cull had already achieved about a third of their target.
Defence spokesman Brigadier Brian Dawson said there were about 9000 eastern grey kangaroos on the Defence-owned site, and they would reduce the population to the ”sustainable level”, a density of one per hectare. This would reduce the population to about 3000.
‘The cull is being conducted humanely by licensed and experienced professional contractors,” Brigadier Dawson said yesterday.’”
[2] Kangaroos Threaten One Of Australia’s Last Remaining Original Grasslands, And Endangered Animals (http://www.sciencedaily.com/releases/2008/05/ 080521114923.htm) “The eastern grey kangaroo (Macropus giganteus) has always been part of the cityscape of Canberra, also known as the “bush capital” of Australia. But even Leipzig-based scientist Dr Marion Höhn and Anett Richter of the Helmholtz Centre for Environmental Research (UFZ) are surprised by the high numbers of them. In her doctoral thesis, Anett Richter is investigating how selected invertebrate species such as ground beetles are affected by landscape fragmentation and habitat alteration in natural grasslands in the Australian Capital Territory (ACT). Yet during her fieldwork she discovered that there were far fewer of them than expected.
What she found instead were dry grasslands, grazed bare and scarred by the worst drought to hit Australia in a century. Particularly, she was surprised to find large quantities of kangaroo dung, especially in the enclosed military areas: “The results of the fragmentation studies are not yet available. But we assume that there is a relationship on individual sites between the extremely high density of kangaroos and species diversity among the invertebrates – especially in times of severe drought.””

In Peter Robertson & Murray Evans, /files/earless-dragon-management-2009-tympanocryptis-pinguicolla.pdf National Recovery Plan for the Grassland Earless Dragon Tympanocryptis pinguicolla, published by the ACT Department of Territory and Municipal Services, Canberra, 2009: http://www.environment.gov.au/system/files/resources/43f24013-b621-4ff6-bf09-34da942e8ced/files/tympanocryptis-pinguicolla.pdf the Canberra International Airport is listed as responsible for the management of earless dragon habitat at the airport (p.9); as possibly relatedly suffering economic impacts (p.12); as supporting ongoing studies p.19.

The Airport legal framework for protecting dragon habitat, including land management agreements and conservation directions, is outlined in section A5.1, p.4:

“Development at the Canberra Airport requires approval for Major Development Plans (MDP) (defined under the Airports Act 1996) from the Minister for Infrastructure, Transport, Regional Development and Local Government (Infrastructure Minister). The Infrastructure Minister, under Section 160(2)(c) of the EPBC Act, must obtain and consider advice from the Minister for the Environment, Heritage and the Arts (Environment Minister). Although an approval may be given by the Infrastructure Minister for a MDP, a permit from the Environment Minister under Section 201 of the EPBC
Act to move, take or kill is required to harm a Grassland Earless Dragon or its habitat. In issuing such a permit the Environment Minister must be satisfied that the action will not have an adverse impact and will contribute significantly to the conservation of the species.”

[3] Don Fletcher, “Population Dynamics of Eastern Grey Kangaroos in Temperate Grasslands,” was on line as a pdf, which is the form I downloaded it as. A copy is preserved now under this article, linked here: /files/Fletcher-kangaroo-thesis.pdf because the pdf is now of limited availability, although copies are still at the University of Canberra Library, reference: http://nla.gov.au/anbd.bib-an42269526. A book by the same title and author has also been published.
[4] There are 100 ha in one square km. So if density varied between 450 and 510 kangs per square km, then that is 4.5 p ha or 5.10 per ha. With 220 per square km 2.2 per ha.
[5] Coulson G, Alviano P, Ramp P, Way S (1999). “The kangaroos of Yan Yean: history of a problem population”, Proc R Soc Vic 111: 121–130.
[6] Penny Olsen and Tim Low, “Situation Analysis Report Update on Current State of Scientific Knowledge on Kangaroos in the Environment, Including Ecological and Economic Impact and Effect of Culling”, School of Botany and Zoology, Australian National University, Canberra, ACT 0200
26 Henry Street, Chapel Hill, Queensland 4049, Prepared for the Kangaroo Management Advisory Panel, March 2006
[7] Don Fletcher, “Population Dynamics of Eastern Grey Kangaroos in Temperate Grasslands”, p.40
[8] In Note 11: “The 2007–08 State of the Environment report states that motor vehicle accidents involving kangaroos has increased by 38% (from 563 in 2005–06 to 777 in 2006–07). Rangers have advised that they now attend more than 1,000 roadside kangaroo incidents per year in Canberra.” Although Maxine is aware that the building of roads and suburbs is impacting the grasslands, she does not stop to think that these are also impacting the kangaroos through an increasing rate of driving them out of their habitats and on to the roads. Nor does Don Fletcher, in his thesis, where he accepts reports on increasing rates of car collisions with kangaroos in Victoria, also a state with a population growth policy which manifests in rapid population growth and development and rapid depletion of kangaroo habitat.
[9] A Pictorial Guide to the Kangaroo Culling Issue (2006) from the ACT Department of Territorial and Administrative Services.

[10] Maxine Cooper Report, pp. xv-xvi
[11] Maxine Cooper Report, pp.74-75 and pp xv-xvi:

“Development that potentially affects lowland native grassland is either underway or planned for the ACT (see Section 5). This development has the potential to sever corridor and connectivity between grasslands and woodlands and/or other adjacent habitats. Many of the recommendations presented in this report reinforce the importance of connectivity.” pp 74-75

“Majura Valley’s large, intact lowland native grassland area, which consists of a number of sites under the control of various government agencies, does not have long-term planning protection; it is not in a reserve and there is no commitment for this to occur.

Given the significance of the Majura Valley grassland, arguably one of the largest areas of Natural Temperate Grassland remaining in southeast Australia, the presence of five threatened species including the Grassland Earless Dragon, it is strongly recommended that a commitment be made to create a reserve in this locality.” [xv-xvi]

[…]defining the site of the proposed Majura Valley reserve would constrain future
development options, for example, the potential Canberra International Airport northern link road and the potential east-west Kowen road, it would provide a more certain context for potential developments. It would also ensure that the Natural Temperate Grassland, the Grassland Earless Dragon and other threatened species are not adversely affected through incremental developments, as would be the case if the potential Canberra International Airport northern link road and the potential east-west Kowen road were to be progressed according to existing concept plans. [xv-xvi]

The lands for the proposed reserve could be the subject of a formal conservation agreement between the ACT and Australian governments.”
[12] Don Fletcher, “Population Dynamics of Eastern Grey Kangaroos in Temperate Grasslands”: “3.3 History of eastern grey kangaroo populations on the sites
All three sites had been grazed commercially for 50 – 150 years until withdrawn in recent decades for conservation or water supply purposes. Each site supported an unmanaged population of eastern grey kangaroos, which was at high density. Kangaroos were scarce in the ACT region in the 1940s and 1950s (Schumack 1977; ACT Kangaroo Advisory Committee 1996, p. 9). This included the study sites. The first employees in the Tidbinbilla Nature Reserve lived there for three months in 1963 before seeing a kangaroo (Mick McMahon, former employee, personal communication; ACT Kangaroo Advisory Committee 1996) and salt blocks were put out to attract kangaroos in the years before the reserve was opened to the public (ACT government official file: Tidbinbilla Fauna Reserve Advisory Committee – 1966).”
[13] Source: The ACT Conservation Council description of the Grassland Earless Dragon – Typanocryptis pinguicolla.
[14] Mt Tyson’s Grassland Earless Dragon: not extinct after all
“Chocolate bilbies are facing stiff market competition from the Grassland Earless Dragon in Mount Tyson on Queensland’s Darling Downs. GED (as the Grassland Earless Dragon is affectionately known) was thought to be extinct, but was rediscovered in 2001. An adult GED grows to around 12 centimetres long and has spotted spiky skin which makes it a camouflage specialist. […] The Landcare Group has received more than $7,000 from the Australian Government to fund a variety of activities designed to promote awareness of GED and create a conservation management strategy for the species. […] The Group had previously received funding through a State Government Community Natural Resource Awareness Activity Grant, which they used to commission the chocolate mould that was provided to manufacture the chocolate dragons. Support has also been provided by local businesses such as Ergon Energy in Toowoomba and by the Queensland Museum and the University of Queensland Gatton campus.”

Original article

Article by Sheila Newman, an environmental sociologist, editor of articles on energy, population, land-use planning and resources. She co-edited the 2005 edition of The Final Energy Crisis, Pluto, UK. Her blog is at http://candobetter.net/SheilaNewman
She also makes environmental and sociological films, including a series on wildlife corridors and kangaroo populations.

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Growling Grass Frog growls for attention as Melbourne’s growth corridors threaten annihilation

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By Sheila Newman, reprinted from Candobetter.net website.

This scientific study into the endangered Growling Grass Frog was released overnight and looks at how the genetic diversity of the frog is being negatively impacted by the rapid urbanisation of Melbourne’s fringe. They were once very abundant in Victoria (so abundant that they used to feed them to the snakes the Melbourne Zoo!) and now only a few populations exist around Melbourne.

The scientists have found a population of the frogs in the Cardinia Shire, which has an increased genetic diversity that they hope to protect.

Claire Keely, the lead scientist on the paper, is both a PhD student and part of the Live Exhibits team at the Melbourne Museum (where they have some of the pretty green frogs in question).

Scientific study finds the vulnerable Growling Grass Frog under increasing threat from rapid urbanisation in Melbourne. (Download paper as full pdf publication here: /files/Genetic stucture and diversity of the endangered growling grass frog in a rapidly urbanizing region.pdf)

A paper by scientists from Museum Victoria and The University of Melbourne has today been published in the Royal Society of London Open Science journal. It describes how the Growling Grass Frog’s genetic diversity is being negatively impacted by rapid habitat loss as Melbourne’s urban fringe continues to expand.

Growling_Grass_Frog_(Litoria_raniformis)_(8615947746)

Urbanisation is a leading cause of species extinction worldwide and is considered a major threat to global biodiversity.

The Growling Grass Frog is listed as vulnerable to extinction in Australia, but isolated populations still persist in the greater Melbourne area. Many of these populations are located in the city’s proposed urban growth area, causing concern as the species is known to be sensitive to habitat fragmentation caused by urbanisation.

The study found that there is decreased genetic diversity in the remaining populations found in Wyndham, Melton and Hume-Whittlesea, making the frogs more prone to inbreeding and less able to cope with the threats posed by urbanisation. The scientists have also found that populations in the Cardinia Shire, one of the four regions studied, are genetically distinct.

“Genetic diversity is key to maintaining the population of Growling Grass Frogs in Victoria as it makes them more resilient to the threats posed by urbanisation. If they are to survive in greater Melbourne the population found in Cardinia will require separate conservation management,” said Claire Keely, PhD student, Museum Victoria and The University of Melbourne, who led the study.

This study demonstrates the importance of genetic research on vulnerable species and can be used to inform conservation efforts to maintain populations.

The team are currently looking to gain further funding to extend the study into the Gippsland region in order to find out more about the frog species genetic diversity and how the Cardinia populations are related to those further east.

The Growling Grass Frog is one of the largest frog species in Australia. They are found in south eastern Australia and were once so abundant in Victoria that they were used for dissections in universities and to feed the snakes the Melbourne Zoo.

For interviews, images, video footage or to meet a Growling Grass Frog at the Melbourne Museum please get in contact.

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IS THE COMMERCIAL KANGAROO INDUSTRY ACTUALLY FARMING KANGAROOS AND AT HIGHER DENSITY THAN NATURAL?

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Sheila Newman: Sociologist and demographer

The literature indicates an understanding among scientists researching in the industry, that these animals are artificially kept by hunting at greater numbers than they would be naturally, in order to both to offset the impact of commercial hunting and to keep it going. The numbers are being manipulated upwards, then the alleged spontaneous overcrowding1 is being used to justify arguments for the need for a commercial industry and damage mitigation culling.2 If the calculations of the program of artificial ‘management’ of kangaroo populations are correct in estimating kangaroo populations too numerous, then the management amounts to a form of farming, which is preventing kangaroos from exercising normal patterns of social organisation that would limit fertility opportunities.

“Caughley (1976, 1977) outlined the principles of wildlife harvesting. To harvest a sustained yield from a population at steady density, it must first be manipulated in some way to promote its rate of increase (e.g. reduce it below its ecological carrying capacity or supplement its resources). The second of the four theoretical principles he identified was that: “Harvesting theory rests upon populations being regulated by some combination of density-dependent reproduction and mortality. This has been described well for a number of large mammals (Fowler 1987). Harvest mortality is seen as being compensated to some extent by lowered natural mortality rates and increased fecundity rates.” (Caughley (1976, 1977) cited by Tony Pople and Gordon Grigg, “Commercial harvesting of Kangaroos in Australia,” Department of Zoology, The University of Queensland, for Environment Australia, August 1999, p.5).

“Even as a pest, however, kangaroos are still a resource, and they can only be that while they remain numerous, a necessity which puts an economic value on their conservation.” (Tony Pople and Gordon Grigg , Commercial harvesting of Kangaroos in Australia, Department of Zoology, The University of Queensland, for Environment Australia, August 1999, pp.38-39)

If my impression is correct, that kangaroo numbers are being manipulated upwards by commercial management practices, then my observations on how these numbers painlessly reduce themselves is more likely to serve the kangaroo conservation and tourism concerns. According to predator-prey theory, predators adapt to prey numbers. Would the kangaroo harvesting industry consider this adaptation, rather than continuing to farm? Like so many industries, it seems to want more growth, so more kangaroos and more territory: The South Australian Commercial Kangaroo Management Plan 2018-2022 indicates a desire to increase the commercial kangaroo meat catchment area by formally extending it3 and by getting more farmers to work for it by shooting kangaroos on their property, through a DEWNR regional staff program.4

POPULATION THEORY

The population model and assumptions in the South Australian Commercial Kangaroo Management Plan 2018-2022 seem to have a number of theoretical flaws and biases, some of which at least have been pointed out in recent research.

– There seems to be an underlying assumption in the population model used (exclusively predator/prey biomass dependent)5 that all the kangaroo species under consideration breed to the maximum (W.D. Hamilton (1964)) unless prevented from doing so by natural catastrophe, big predators and human culls for commercial or other reasons. Whilst Hamilton’s rules for inclusive fitness and Dawkins’ theory on selfish genes are very important, they should not cause a failure to investigate countervailing forces to genes seeking maximum reproduction.

Demographic brakes

Countervailing forces to reproductive urges exist in the subtleties of endogamy (breeding within a local population) and exogamy (incest avoidance)6 which also limit fertility opportunities, including, in some species, sexual maturation.7 For instance, young male kangaroos need to leave their natal group because there is only room for one dominant male breeder and he monopolises all the females unless another mature male successfully challenges him. The dispersing young male may not find a group that has available females or he may fail to successfully compete for them. Aspects of cooperative breeding may be present8 and delay sexual maturation in both males and females. This would explain some variations in breeding ages in different populations and environmental circumstances.9 These should limit fertility opportunities in a natural ecology, i.e. one not impacted by the commercial management considerations noted above.

My own theory is that undisturbed local populations respond to environmental cues like rainfall and soil richness by a variation in genetic algorithms for fertility. Sexual maturation and pairing is limited by the availability of territory. In humans these algorithms translate into kinship and marriage rules that vary in degree according to rainfall and other environmental cues.10

 

Demographic accelerators

But we have abundant examples demonstrating that, because of hunting and culling, more fertility opportunities are being created for younger, smaller animals.

“Commercial harvesting may affect the demography (e.g. size, growth, distribution and birth and death rates) of harvested kangaroo populations by selecting the larger kangaroos, which tend to be the older males (Allendorf et al. 2008). Commercially harvested populations may have a lower average age compared to that of unharvested populations. The average size of kangaroos in harvested populations may be lower, and populations contain a higher proportion of young animals than unharvested populations, but these differences are lessened during drought when older animals are lost from unharvested populations (Pople 1996).The sex bias (i.e. the percentage of harvested kangaroos that are male) has increased from 60-70% male to 92-97% male for red and western grey kangaroos (DEWNR 2017). The increase in sex-bias is due, in part, to some meat processing plants only accepting male carcasses. The sex bias of the euro harvest has historically been higher due to the small size of female euros, but the sex-bias has also increased from 75-95% male to 99% male (DEWNR 2017).” (South Australian Commercial Kangaroo Management Plan 2018-2022, p.25.)

Massive bias for shooting large males leaves remaining, smaller males, without the suppression of sexual maturation (possibly) or sexual behaviour (definitely) that those large competitive mature males would have caused. The remaining smaller males do not need to disperse from their natal group to breed. The natal groups may be so fragmented that most adult relatives have disappeared and the remaining young does and bucks may lack the normal incest avoidance due to disturbance of Westermarck relationships. It is also possible that the presence of mature related males and females may delay sexual maturity or behaviour in female kangaroos, so that loss of big males and females would then also favour early breeding in young does.

And the industry knows this:

“To harvest a sustained yield from a population at steady density, it must first be manipulated in some way to promote its rate of increase (e.g. reduce it below its ecological carrying capacity or supplement its resources).” (Caughley (1976, 1977) cited by Tony Pople and Gordon Grigg (1999))11

If there were really a desire to achieve smaller kangaroo populations naturally, then a number of things could be tried. Assuming that the disorganisation caused by hunting and culling is responsible for managing the population numbers upwards, we might create reliably safe areas and corridors local to various kangaroo clans in the harvesting area so that they could adapt to protect dependent young and females, encouraging the Westermarck effect, normalisation of patterns of incest avoidance and dispersal, weight, rate of maturity, sexual competition and fertility response to environment. If this succeeded it would reduce both the perceived need and the opportunity for the commercial industry as well as damaging the kangaroo’s reputation for overpopulation. These refugia could also provide a safe and permanent environment away from the massive human population expansion and landscape transformation which also uproots, scatters and kills kangaroos.

More demographic Brakes: Sexual Segregation/Gender pathways

Some other variations in population organisation can affect fertility opportunities. Examples include separate gender pathways, with ‘sexual segregation’ where male and female populations live apart.

“Sexual segregation is a phenomenon seen in many species, with segregation occurring along behavioural or ecological dimensions. Sexual segregation in western grey and red kangaroos in semi – arid Victoria has been the subject of intensive investigations since the last review.

[…] MacFarlane and Coulson (2005) investigated the effects of mating activity, group […] composition, spatial distribution and habitat selection on sexual segregation in western grey and red kangaroos. The synchrony and timing of mating activity was seen to influence the magnitude and timing of social segregation in these species, with mixed sex groups predominating during the breeding season. …

… Spatial segregation and habitat segregation were also seen. Although the magnitude of these types of segregation were weaker, they were both still significantly influenced by synchrony and timing of breeding.

Coulson et al. (2006) discussed sexual segregation at three levels (habitat, social and dietary) and confirmed that both size and sex influence segregation.

MacFarlane and Coulson (2009) showed that the need for males to maintain contact with other males (perhaps to develop important fighting skills, evaluate rivals and establish a dominance hierarchy) might also promote sexual segregation.

Similarly Nave (2002) reported evidence of sexual segregation in eastern grey kangaroos in Victoria.” (Review of Scientific Literature Relevant to the Commercial Harvest Management of Kangaroos http://www.environment.nsw.gov.au/resources/nature/110641Kangaroolitreview.pdf)

What are the consequences of loss of sex-specific territory?

Years ago, Glen Marshall, who was a teacher and missionary in PNG between 1960 and 197412 told me that fertility shot up when churches convinced men and women to cohabit, where previously they had separate land and houses. I was later able to study this concept in detail and wrote a book about how Pacific Islander land-tenure and inheritance traditions kept populations within the limits of small islands.13

What effect could reduction of habitat, forced cohabitation, forcibly changed migration routes and wiped out populations have on male/female kangaroo territory and consequently on fertility opportunities?

How do we know that the female bias (recorded by Fletcher, 2006) at Tinbinburra, for instance, is not due to that area being female territory?

Female elder kangaroos

Daughters seem to learn from their mothers to look after joeys. Where female kangaroos are early orphaned their parenting skill may increase risks in joey upbringing. The extraordinary rates of joey mortality may have something to do with this. (See Faces in the Mob for a study of success and failure in raising joeys in one mob.)

How far do kangaroos migrate?

Another aspect of population theory is migration. The range of kangaroo movement is probably greatly underestimated in calculations that do not take more recent MT DNA studies into consideration, such as Zenger et al DNA study 2003.14 Zenga et al look at Eastern kangaroo populations, but I note that South Australia uses the NSW model anyway.15 Seeing as the South Australian Commercial Kangaroo Management plan encourages research, I would suggest it undertake MT DNA studies similar to Zenger et al’s for South Australian populations. Underestimation of real geographical range risks skewing the estimation of population numbers by confusing seasonal or reactive population movement with permanent populations: Pople et al (2007)16 acknowledged that temporal and spatial kangaroo population movement had been ignored in the models and it does not seem to be taken into consideration in the South Australian Management Plan yet. Pople et al did not, however, consider the discrete dynamics within local populations and their interactions with other populations within the overall area. They were looking at a commercial hunting model seeking to predict when and where populations would be grouped together and easier to harvest economically.

Effectively the counting method and population model in the South Australian Management plan seems to assume an undifferentiated ‘metapopulation’ and to ignore the local populations that actually make up that metapopulation and which have their own local characteristics of endogamy, exogamy, dispersal and philopatrie) within that metapopulation.

“A metapopulation is a population of populations (Hanski & Gilpin 1991). Wright (1940) laid the groundwork for a genetic theory of metapopulations, while Andrewartha & Birch (1954, Ch.14) did the same for metapopulation dynamics: ‘A natural population occupying any considerable area will be made up of a number of local populations or colonies. In different localities the trend may be going in different directions at the same time.’ They emphasized the influence of dispersal on the number of patches occupied at any given time.” (Caughley, Directions in Conservation Biology, Journal of Animal Ecology, Vol. 63, No. 2 (Apr., 1994), pp. 215-244, p. 221)

ENVIRONMENTAL DAMAGE MITIGATION & ROO DENSITY: THEORY & EXPERIMENT

Goal: […] to provide an alternative management option for reducing the damage to land condition caused byoverabundant kangaroos. (The South Australian Commercial Kangaroo Management Plan 2018-2022, p.4.)

The South Australian Commercial Kangaroo Management Plan 2018-2022 seems to rely, as mentioned above, on a predator/prey, biomass dependent population theory, and to cite a small group of scientists who have apparently confirmed this theory time and again, describing how kangaroos wear down grasslands and then starve to death. One scientist not cited is ACT Ecologist Donald Fletcher, whose extensive field research failed to confirm the theory. The ACT Kangaroo Management model relies on the same literature as the South Australian Commercial Kangaroo Management Plan, and is one of high fertility sedentary populations that rarely migrate, grazing grasslands down to the subsoil. But, in his 2006 thesis, p. 237, Senior ACT Kangaroo management ecologist, Donald Fletcher, tested this model and found, to his surprise, that,

“The study did not provide evidence that high densities of kangaroos reduce groundcover to the levels where erosion can accelerate.

Unmanaged kangaroo populations did not necessarily result in low levels of ground cover. Groundcover had a positive but not significant relationship to kangaroo density, with the highest cover at the wettest site where kangaroo density was highest. Weather has an important influence on groundcover.”

“The results from the study as a whole indicate that unmanaged kangaroo populations did not necessarily result in unacceptably low levels of ground cover.” (Fletcher Phd: p.231.)

1 “Harvesting will invariably involve some injuries and protracted deaths. However, this must be weighed up against compensatory mortality, reduction in other forms of killing when an animal changes status from a pest to a resource, the quality of life for individuals in dense, unharvested populations during droughts and alternative land uses if harvesting is not allowed.” Tony Pople and Gordon Grigg,“Commercial harvesting of Kangaroos in Australia,” Department of Zoology, The University of Queensland, for Environment Australia, August 1999, p.2).

2 “Australia’s problem with abundant kangaroo species

Australia has about 50 species of marsupial mammals of the Super-family Macropodoidea. Most of them have declined in the 210 or so years since Europeans settled here, some to extinction. Some, however, have thrived to the extent that they are now among the most abundant large mammals anywhere. The abundant species, particularly the three largest species of kangaroo, are so numerous in many rural areas that they are regarded as pests, in competition with sheep and cattle for pasture which, in a dry country like Australia, is always in short supply.

The abundance of kangaroos, with their high conservation status, and the recognition that they are regarded as a serious pest by graziers gives Australian conservation agencies a problem. Not surprisingly, all Australian macropods are protected by law, as is almost all Australian wildlife. The solution to this conflict has been to issue limited permits which allow kangaroos and some of the most numerous wallabies to be shot as pests. However, most of the control is effected through permitting a regulated commercial harvest of kangaroos and wallabies for meat and for leather.

Any commercial harvest or pest destruction of wildlife is likely to be controversial, especially if the subjects are as appealing and as well known as Australia’s kangaroos. That kangaroos are the most readily identified symbol of Australia, and that they are harvested by shooting, only exacerbates the concern, and it is not uncommon for there to be organised public campaigns against their commercial use. […]

[…] The individual aims of the Management Programs differ a little between the different States but, in general, all identify the need to balance land-use requirements against the necessity to ensure continuation of self perpetuating kangaroo populations of all species. Tony Pople and Gordon Grigg,“Commercial harvesting of Kangaroos in Australia,” Department of Zoology, The University of Queensland, for Environment Australia, August 1999, p.2).

3 “However, within the life of this plan, new Commercial Harvest Sub-Regions may be opened, on the basis of population surveys, in areas of South Australia where commercial harvesting of kangaroos is not currently occurring. The Commonwealth Government will be advised of the quotas annually through the Quota Report before implementation.” South Australian Commercial Kangaroo Management Plan 2018-2022, p.10

4 “Action 8: Educate DEWNR regional staff and land managers on best practice for combining the use of commercial and non-commercial techniques for kangaroo management.

Performance indicators:

8.1 Develop decision-making tools to assist regional staff in providing advice to land managers on commercial vs.non-commercial kangaroo management.

8.2 Any landholder seeking a destruction permit for more than a specified number of kangaroos (determined seasonally) within a CHMR is asked to consider using the commercial harvest option in the first instance. In such circumstances, Permits to Destroy Wildlife (Kangaroos) are only offered after the commercial harvest option has been declined.

8.3 Investigate the introduction of formal training requirements (like those undertaken by Kangaroo Field Processors) for landholders requesting a non-commercial Permit to Destroy Wildlife (Kangaroos).

8.4 Investigate alternative ways to integrate commercial and non-commercial kangaroo management options to mitigate damage to land condition.” (South Australian Commercial Kangaroo Management Plan 2018-2022, p.8.)

5 Simplification of population dynamics in pasture biomass model: “Briefly, changes in kangaroo numbers are modelled as a function of pasture biomass which, in turn, is determined by recent rainfall, past pasture biomass and the density of kangaroos (and livestock) consuming the pasture. Harvesting obviously reduces kangaroo numbers, but the reduced density results in higher pasture biomass and therefore higher rates of increase of kangaroos. This improvement in environmental conditions for a population, which without harvesting has no long-term trend, is a basic requirement for the sustainability of a harvest. The population can be simulated 10,000 times over a 20 year period. Each run is different as, every three months, rainfall is drawn from a probability distribution using the average and standard deviation for rainfall in western NSW and thus reflects the uncertain food supply in this arid environment. Population size is also estimated with uncertainty by aerial surveys, and so this too was drawn from a probability distribution using the average and standard deviation associated with aerial surveys (Pople 2008). The population was harvested at an annual rate of 15 percent or less if it was below a particular threshold.” (Source: Appendix 3, pp31-32, South Australian Commercial Kangaroo Management Plan 2018-2022.)

6 “[Inbreeding is ]a lesser problem in natural populations because mating between close relatives is uncommon and individuals often actively avoid mating with close relatives (Ralls, Harvey & Lyles 1986). Caughley, Directions in Conservation, Journal of animal ecology, 1994 Vol: 63 Issue: 2 Page: 215 -2441994, pp220-221. Sheila Newman, Demography, Territory, Law: The rules of animal and human populations, Countershock Press, 2013.

7 See introduction and most chapters in Nancy G. Solomon and Jeffrey A. French, Cooperative Breeding in mammals, Cambridge University Press, 1997. See “Chapter 4: Towards a new social theory on population density and geometric patterning” in Sheila Newman, Demography, Territory, Law: The Rules of Animal and Human Populations, Countershock Press, 2013, (http://catalogue.nla.gov.au/Record/6537280, https://www.amazon.com.au/Demography-Territory-Law-animal-populations-ebook/dp/B00ALE8YSA, http://www.lulu.com/au/en/shop/sheila-newman/demography-territory-law-rules-of-animal-human-populations/paperback/product-21735874.html) and Sheila Newman, The Urge to Disperse, Candobetter Press, 2012. (https://www.amazon.com/Urge-Disperse-Sheila-Newman/dp/1446784134).

8 https://espace.library.uq.edu.au/view/UQ:382445

9 Kangaroos at risk gives examples of variations in breeding age in different populations. http://www.kangaroosatrisk.net/2-biology–population-ecology.html

10 “Chapter 4: Towards a new social theory on population density and geometric patterning” in Sheila Newman, Demography, Territory, Law: The Rules of Animal and Human Populations, Countershock Press, 2013, (http://catalogue.nla.gov.au/Record/6537280, https://www.amazon.com.au/Demography-Territory-Law-animal-populations-ebook/dp/B00ALE8YSA, http://www.lulu.com/au/en/shop/sheila-newman/demography-territory-law-rules-of-animal-human-populations/paperback/product-21735874.html) and Sheila Newman, The Urge to Disperse, Candobetter Press, 2012. (https://www.amazon.com/Urge-Disperse-Sheila-Newman/dp/1446784134).

11 (Caughley (1976, 1977) cited by Tony Pople and Gordon Grigg, “Commercial harvesting of Kangaroos in Australia,” Department of Zoology, The University of Queensland, for Environment Australia, August 1999, p.5).

12 Sheila Newman, “Suppression of matriarchal societies and population stability in Papua New Guinea 1960-1974,” Interview with Glen Marshall, https://candobetter.net/node/4382. Although this may seem an anecdotal sort of interview, separate men’s and women’s land in Micronesia, even today, and elsewhere, is a well-established fact in anthropology.

13 Sheila Newman, Demography Territory Law: The Rules of Animal and Human Populations, Countershock Press, 2013. This also explores the Easter Island population crash narrative.

14 Zenger et al DNA study 2003: (Heredity (2003) 91, 153–162. doi:10.1038/sj.hdy.6800293, K R Zenger, M D B Eldridge and D W Cooper, “Intraspecific variation, sex-biased dispersal and phylogeography of the eastern grey kangaroo (Macropus giganteus).” http://www.nature.com/hdy/journal/v91/n2/full/6800293a.html

15 “South Australia has adopted the harvest thresholds method used in New South Wales and described in the New South Wales Commercial Kangaroo Harvest Management Plan 2017-2022. The following explanation on harvest threshold setting by SR McLeod and AR Pople (2011), is taken from the NSW Commercial Kangaroo Harvest Management Plan.” (Appendix 3: Setting and applying harvest Thresholds, South Australian Commercial Kangaroo Management Plan 2018-2022, p.28.)

16 “Whether the goal is conservation, sustainable use or pest control, wildlife management ideally requires regularly updated information on a population’s size and distribution. Most frequently, population size is estimated from sample counts throughout a study area, but the pattern of distribution is either ignored or considered subjectively. Typically, management actions such as setting appropriate seasonal harvest limits or culling are triggered by estimates of the total population without sufficient regard to its spatial and temporal distribution. This means that management actions may be focused inappropriately, leading to wastage of money and outcomes that may be seriously suboptimal. Management actions would benefit from readily available and up-to-date information about the distribution of wildlife populations within a region, as well as the total population size. To do this, point-based sampling data need to be translated to density surfaces. Density surfaces modelled using geostatistics or habitat models have been produced from ground and airborne surveys of marine (e.g. Augustin et al. 1998; Rivoirard et al. 2000) and terrestrial (e.g. Campbell & Borner 1995; Rempel & Kushneriuk 2003) wildlife populations. However, few, if any, studies have modelled wildlife density over a large spatial and temporal extent, thereby providing local estimates of population size to inform more focused management actions.” (Pople, Phinn, Menke, Grigg, Possingham, McAlpine, “Spatial patterns of kangaroo density across the South Australian pastoral zone over 26 years: aggregation during drought and suggestions of long distance movement,” Journal of Applied Ecology 2007 44, 1068–1079)

(featured image: Animals Australia)

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Media Release: “Canberra Kangaroo culls rely on stale politicized science”

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MEDIA RELEASE: 15 May 2016: “Canberra Kangaroo culls rely on stale politicized science”: Australian Wildlife Protection Council says

Today, Maryland Wilson, AWPC President, said that Evolutionary Sociologist, Sheila Newman recently reviewed the government science behind the ACT culls, which will begin anew on Monday 16 April 2016. Newman found it excessively narrow, self-referencing, mechanistic and old-fashioned.   Newman reported in Conference Paper: REVIEW OF SCIENTIFIC BASIS OF CANBERRA’S KANGAROO CULLS that:

“Harvesting, damage mitigation and culling probably actually accelerate population growth in roos because the smaller ones survive and adapt by sexually maturing earlier – which speeds up fertility turnover.

Since 2003 DNA studies have shown that ACT and southern NSW roos, both male and female, migrate at significant rates and for longer distances than the ACT model assumes. Migration has probably been mistaken for fertility, rendering ACT roo counts unreliable and invalid. The ACT needs to stop culling and widen its research base to consider various genetically based algorithms that naturally restrain fertility opportunities in kangaroos.”

Examples of such algorithms include separate gender pathways, with ‘sexual segregation’ where male and female populations live apart. It is likely that the stable presence of mature dominant males and females in family and mob organisation inhibits sexual maturity and activity as has been shown in studies of other species, such as macaques and superb fairy wrens (the latter cooperative breeders). In humans, girls brought up with step-fathers who came late to the family were more likely to mature sexually earlier due to absence of Westermarck Effect.)”

“The ACT’s senior Ecologist, Donald Fletcher, found in his Phd that local kangaroos lived without damaging pasture or starving at densities of 5 per hectare, yet he had supported the ACT program that deems kangaroos at more than one per hectare to be in danger of starving and a threat to their own habitat.” 

crueltyillegalherdingcrashing

The ACT government in Canberra is pursuing a policy of rapid human population growth, mostly through publicly invited economic immigration, yet it blames kangaroos for being crowded out of the suburbs.

In June 2016 ACT – South West Australian Capital Territory was the fastest growing area in Australia and grew by 127.3%. (ABS http://www.abs.gov.au/ausstats/abs@.nsf/mf/3218.0)

“Planned wildlife corridors need to be made safe and long-term viable to cope with people, car and kangaroo population movements. Most Australians love kangaroos and don’t want rapid human population growth. Australia’s capital needs to revise its growth policy in line with sustainability, democracy and appreciation of our unique ecology,” said Maryland Wilson, President, AWPC.

CONTACT: MARYLAND WILSON: 613 359788570 and 61417148501 and SHEILA NEWMAN 0412319669

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Petition: end the slaughter of kangaroos in the ACT

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Frankie Seymour’s petition:

Australian Capital Territory government is still killing thousands of kangaroos every year in a cruel, unnecessary, ineffective and ecologically destructive annual slaughter on public reserves. This has been going on since 2009, and we expect the latest slaughter to be announced any day.

In 2015, the Australian Capital Territory government authorised the slaughter of at least 25772 kangaroos across the Territory. Most of these were to be killed on farms because farmers believe that native kangaroos compete for pasture with introduced livestock.

*Overwhelming evidence has shown that the slaughter is: ineffective in terms of reducing kangaroo grazing pressure on reserves (because kangaroos are pretty mobile within their ranges, and quickly move in from nearby farms to make use of the empty space);

*unnecessary (because eastern grey kangaroos are so slow breeding, have such a high infant mortality rate and manage their own populations effectively in times of food shortage); and

*actively harmful to ecosystems (because kangaroo grazing ensures diversity of habitat for a great diversity of others species, many of which cannot thrive in either ungrazed land or livestock grazed land).

The evidence also shows that the government’s kangaroo counts are inherently inaccurate.

Evolutionary sociologist and AWPC policy advisor, Sheila Newman, has criticised the research base used in the ACT Kangaroo Management program. (See https://candobetter.net/node/4822). Her review of the literature concludes that “culling” may actually increase kangaroo populations by speeding up reproduction, with the selecting in of smaller, earlier maturing kangaroos and the selecting out of big, mature animals, in a harvested population like effect.

ACT kangaroo management of kangaroos is narrowly based on numbers, rather than mob dynamics. “Culling” can increase mob sizes, as it destroys mob control from larger, mature adults, and gives breeding opportunities to younger animals.  Ms Newman says: “…harvesting, damage mitigation and culling probably accelerates population growth in roos” because of the ‘harvesting effect’ on their evolution which tends to select-in smaller animals which reproduce earlier.

The government’s own ecologist has admitted that the government’s assertions about kangaroos being a threat to vulnerable species were just “PR”, and that its claim that killing kangaroos will benefit biodiversity generally is based on a simplistic assumption that more biomass (vegetation) is better for biodiversity than the diversity of vegetation achieved by kangaroo grazing.

Furthermore, evidence shows that even the weak and cynical provisions of the Code of Practice are not obeyed. Although the Code of Practice requires kangaroos not killed instantly to be immediately euthanased by a shot to the head or heart, one young male kangaroo found in a government burial pit had been shot, bludgeoned, stabbed, then died of either blood loss, or possibly suffocation from being buried while still alive.

The ACT government must stop hiding behind its out-dated Kangaroo Management Plan, start looking at the actual evidence, and take some measure of responsibility for its own decisions.

Sign this Petition: End the slaughter of kangaroos on public land in the Australian Capital Territory.

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Video & notes: Kangaroos, culling and Canberra – presentation to AJP event 5 April 2016

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Video and text of Sheila Newman’s speech at the Animal Justice Party’s event, “Policy basis for Kangaroo treatment in the ACT,” 5 April 2016: Harvesting, damage mitigation and culling probably actually accelerate population growth in roos because the smaller ones survive and adapt by sexually maturing earlier – which speeds up fertility turnover.

Since 2003 DNA studies have shown that ACT and southern NSW roos, both male and female, migrate at significant rates and for longer distances than the ACT model assumes. Migration has probably been mistaken for fertility, rendering ACT roo counts unreliable and invalid. The ACT needs to stop culling and widen its research base to consider various genetically based algorithms that naturally restrain fertility opportunities in kangaroos.

Examples include separate gender pathways, with ‘sexual segregation’ where male and female populations live apart. It is likely that the stable presence of mature dominant males and females in family and mob organisation inhibits sexual maturity and activity as has been shown in studies of other species, such as macaques and superb fairy wrens (the latter cooperative breeders). In humans, girls brought up with step-fathers who came late to the family were more likely to mature sexually earlier due to absence of Westermarck Effect.)

Planned wildlife corridors need to be made safe and long-term viable to cope with people, car and kangaroo population movements.

Canberra is pursuing a policy of rapid population growth, mostly through invited economic immigration.

In June 2016 ACT – South West Australian Capital Territory was the fastest growing area in Australia and grew by 127.3%. (ABS http://www.abs.gov.au/ausstats/abs@.nsf/mf/3218.0)

Canberra’s population could increase to 904,000 by 2061 according to new projections released by the Australian Bureau of Statistics. It’s not inevitable, but the government would like you to believe it is.

planned-economic-mig-med

Predicting a population growth of at least 98 per cent within 50 years, ACT population projections for 2061 suggest that the Australian Capital Territory population could exceed Tasmania’s population by 2038.

But some think that the ACT’s biggest problem is its kangaroo population. It’s not the new suburbs, the new roads, the new airport, the additional schools, hospitals, houses, and all the new cars that threaten Canberra’s grasslands: it’s the eastern grey kangaroos.

It seems that it is better to have cattle in Canberra’s nature parks than kangaroos.

Ecological cattle grazing is now being trialed. Cattle can be more easily moved than kangaroos. (Fletcher, Senior Ecologist, communication to P. Machin.)

ecological-grazing-sign2

Although, Fletcher had previously described the devastation cattle made to grass cover in no uncertain terms: “Fletcher Phd: p.37. “70 pregnant cows and four bulls grazed for ten weeks at Tidbinbilla after a bushfire in January 2003 (Section 3.5.1). Prior to their arrival, there had been an atypical abundance of pasture due to the death of almost half of the Tidbinbilla kangaroos in the bushfire, but by the time the cattle were removed, the Tidbinbilla pasture had been reduced to the lowest herbage mass recorded on any site during the study.”

effects-cattle-grazing-tidbinbilla-fletcher
ACT Kangaroo Management Policy works on a model that all creatures maximize their population growth and that Canberra’s roos are riding an expansive curve which can only be capped by massive frequent culls. A stated fear is that they will otherwise graze and drastically modify biodiversity of Canberra’s grasslands. Another is that roos need periodically to be shot so as to save them from starving to death.

Why culling is better than harvesting (ACT Senior Ecologist, Don Fletcher)

“[…] the model indicates that commercial harvesting (currently under trial in the region, at the maximum level allowed, results in a sustainable harvest of kangaroos, but does not increase the herbage mass, and only slightly reduces the frequency of crashes when herbage mass falls to low levels. (To demonstrate this with an ecological experiment would require an extremely large investment of research effort.)

However, an alternative ‘national park damage mitigation’ formula, which holds kangaroo density to about 1 ha -1 , is predicted to increase herbage mass considerably and to reduce the frequency of crashes in herbage mass, but these effects would be achieved at the cost of having to shoot large numbers of kangaroos.” (Fletcher Phd: Population dynamics of Eastern Grey Kangaroos in Temperate Grasslands, 2006, p. vi.)

The model and the reality

The ACT Roo Management model is one of high fertility sedentary populations that rarely migrate, grazing grasslands down to the subsoil. But, in his 2006 thesis, p. 237, Senior ACT Kangaroo management ecologist, Donald Fletcher, tested this model and found, to his surprise, that,

“The study did not provide evidence that high densities of kangaroos reduce groundcover to the levels where erosion can accelerate.

Unmanaged kangaroo populations did not necessarily result in low levels of ground cover. Groundcover had a positive but not significant relationship to kangaroo density, with the highest cover at the wettest site where kangaroo density was highest. Weather has an important influence on groundcover.”

“The results from the study as a whole indicate that unmanaged kangaroo populations did not necessarily result in unacceptably low levels of ground cover.” (Fletcher Phd: p.231.

The Kangaroo Migration factor

Since 2003 DNA studies have shown that ACT and southern NSW roos, both male and female, migrate at significant rates and for longer distances than the ACT model assumes.

Migration has probably been mistaken for fertility, rendering ACT kangaroo counts unreliable and probably invalid.
DNA studies 2003 show migration a strong factor

Zenger et al (2003)[1] found that mitrochondrial DNA samples indicated about 22.61 individuals per generation migrated with a range of 8.17-59.30. In female immigrants the range was 2.73 with a range of 0.60-12.16. Although females demonstrate smaller migration rates compared to the sexes combined, the values are still comparatively high. Analysis across NSW showed populations separated by up to about 230km had equivalent numbers of close relatives when compared to populations only about 20km apart.

This contradicted field study opinion that migration was low in eastern grey kangaroos, and especially low in females in the ACT. Tidbinbilla (a Canberra nature park studied by Fletcher) featured in the Zenger et al study.

Zenger: Mt DNA findings contrary to Migration views in Fletcher thesis

“Throughout their lives eastern grey kangaroos are relatively sedentary (Johnson 1989) compared to red kangaroos (Priddel 1987). A partly concurrent study of eastern grey kangaroo habitat use and movements on the Googong and Tidbinbilla sites found the eastern grey kangaroos on these sites were sedentary in all seasons (minimum convex polygon mean size 0.43 km 2 ± 0.06 SE and 0.61 km 2 ± 0.08 respectively; Viggers and Hearn 2005). Kangaroos were not radio tracked at Gudgenby but my observations suggest there is no more movement of eastern grey kangaroos on and off the site there than at Tidbinbilla. Thus it is likely there was little net movement of kangaroos on and off the study sites.” (Fletcher, page v.)

Paradoxical impact of Culls, kills and Harvests

Harvesting, damage mitigation and culling probably actually accelerate population growth in roos because the smaller ones survive and adapt by sexually maturing earlier – which speeds up fertility turnover.

Harvested stock grow smaller, breed earlier, faster

“Smaller, earlier breeding genetic stock tend to escape harvesting”. See, e.g. J.J. Poosa, A. Brannstrom, U. Dieckmann, “Harvest-induced maturation evolution under different life-history trade-offs and harvesting regimes.” (See note for more literature on this.)[2]

Fletcher, on estimates of biomass consumption per roo allows for large variations in harvested populations vs wild populations.

“How big are eastern grey kangaroos?
The mean live weight of eastern grey kangaroos taken from the unshot population at Tidbinbilla was 29 kg – smaller than the 35 kg mean live weight assumed in the Kinchega kangaroo study (Caughley et al. 1987). Based on the size relationship between shot and unshot populations of kangaroos in South Australia and Queensland (Grigg 2000), the mean size of eastern grey kangaroos in equivalent shot populations was predicted to be 17 kg live weight. The minimum dressed size accepted by operators of commercial chillers is 17 kg, implying that many of the kangaroos in shot populations (on rural properties) in the ACT region are too small to attract commercial shooters.”(Fletcher, p.242.)

Culling has a similar effect.

Earlier maturation would contribute to higher population growth rates. What role does harvesting, culling and farm mitigation killing play in accelerating breeding rates?
“Smaller, eat less, more numerous, more fecund”, reproduce earlier

“The management implications arising from this study are numerous and a full account would require a separate report. As one example, kangaroos in these temperate grasslands are on average smaller, eat less, are more numerous, and are more fecund, than would be predicted
from other studies (e.g. Caughley et al. 1987). Thus the benefit of shooting each kangaroo, in terms of grass production, is less, or, in other words, more kangaroos have to be shot to achieve a certain level of impact reduction, and the population will recover more quickly, than would have been predicted prior to this study.” (Fletcher, p245.)

Kangaroos shot in Tidbinbilla and low weight in shot populations

“The mean live weight of eastern grey kangaroos in high density populations can be estimated from the weights of a sample of 332 kangaroos shot at Tidbinbilla in June 1997 (Graeme Coulson, personal communication, 2003) to be 29 kg. (That is an adjustment of the actual mean liveweight of the shot sample, 26.4 kg, to allow for seasonal effects, as explained in Discussion. Kangaroos in shot populations, such as on grazing properties, are likely to be smaller due to selective harvesting, also explained in Discussion).”(Fletcher p.242.)

Wider Research Base needed

In my view, the ACT needs to stop culling and widen its research base to consider encouraging various genetically based behaviours that naturally restrain fertility opportunities in roos.

Known examples include incest avoidance, which limits breeding unless animals can disperse to their own territory. [3]
Sexual segregation and gender pathways, where male and female populations live apart.

Incest avoidance as a spatial limiter of breeding opportunity

Many examples of suppressed maturity or breeding in both males and females close by related adults in many species. (Sheila Newman, Demography Territory Law: Rules of animal and human populations, Countershock Press, 2013, chapter 3.) (Paperback edition and Kindle edition.)

In kangaroos male sexual dominance and monopolisation of females is a very obvious trait. (The effect of dominant close females on female maturation is less known and should be investigated as it has been in other species).

Where large males and females are removed from mobs, these limiting population effects are also removed. What happens then?

kinship-incest-avoidance-8th-degree

The following diagram is of human kinship rules, however similar patterns of incest avoidance occur in other species, and in kangaroos. The diagram for humans is split into family and in-laws and sets out some typical rules for incest avoidance in low fertility environments – central Australia and mountainous South Korea. The rules for inlaws are reproduced back to front to demonstrate a mirror-like effect. The person in the top left corner, ‘You” may not conceive/marry any of the people in the black squares. That leaves only eight possible mates – as long as they are not already married. Imagine how hard it would be to find a wife or husband under these circumstances in a sparsely populated society of small clans that only travelled on foot, without cars, planes or boats. In a more fertile environment, the rules of incest avoidance are usually much less strict, as in Leviticus, where people may marry their first cousins – giving much greater fertility opportunities, even without the benefit of modern transport. For more about this and how it affects human economies see: “Overpopulation: Endogamy,Exogamy and fertility opportunity theory”.

The following two diagrams are from Zenger et al (2003).
They show the regions from which their eastern grey kangaroo DNA samples were taken, and they give a ‘family tree’ of roo DNA diversity, which shows greatly decreased diversity in north NSW and in Queensland. The authors could find no explanation for this.

zenger-et-al-Fig1-map-geographic-distrib-med

commercial-harvesting-roos-Aust-map-med

Harvesting has gone on for a long time in these regions. We know it is associated with marked size decrease. It seems likely that it is also associated with earlier sexual maturity. Consider the possibility that, as well as size decrease and earlier sexual maturation in harvested populations, the decrease in genetic diversity present in those populations may be due to inbreeding resulting from loss of family structure and associated incest avoidance, with decreased migration as small early maturing roos settle for their siblings. There seems little will to investigate this. Although there is some literature, it is very limited. (See note [2].)

Sexual Segregation/Gender pathways

Review of Scientific Literature Relevant to the Commercial Harvest Management of Kangaroos http://www.environment.nsw.gov.au/resources/nature/110641Kangaroolitreview.pdf

“Sexual segregation is a phenomenon seen in many species, with segregation occurring along behavioural or ecological dimensions. Sexual segregation in western grey and red kangaroos in semi – arid Victoria has been the subject of intensive investigations since the last review.

[…] MacFarlane and Coulson (2005) investigated the effects of mating activity, group […] composition, spatial distribution and habitat selection on sexual segregation in western grey and red kangaroos. The synchrony and timing of mating activity was seen to influence the magnitude and timing of social segregation in these species, with mixed sex groups predominating during the breeding season. …

… Spatial segregation and habitat segregation were also seen. Although the magnitude of these types of segregation were weaker, they were both still significantly influenced by synchrony and timing of breeding.

Coulson et al. (2006) discussed sexual segregation at three levels (habitat, social and dietary) and confirmed that both size and sex influence segregation.

MacFarlane and Coulson (2009) showed that the need for males to maintain contact with other males (perhaps to develop important fighting skills, evaluate rivals and establish a dominance hierarchy) might also promote sexual segregation.

Similarly Nave (2002) reported evidence of sexual segregation in eastern grey kangaroos in Victoria.”

What are the consequences of loss of sex-specific territory?

Years ago a man who had worked in PNG told me that fertility shot up when churches convinced men and women to cohabit, where previously they had separate land and houses.

What effect could reduction of habitat, forced cohabitation, forcibly changed migration routes and wiped out populations have on male/female kangaroo territory and consequently on fertility opportunities?

How do we know that the female bias (recorded by Fletcher) at Tinbinburra, for instance, is not due to that area being female territory?
Female elder kangaroos

Daughters seem to learn from their mothers to look after joeys. Where female kangaroos are early orphaned their parenting skill may increase risks in joey upbringing. The extraordinary rates of joey mortality may have something to do with this. (See Faces in the Mob for a study of success and failure in raising joeys in one mob.)
In conclusion, regarding ACT Kangaroo management:

It seems that ACT Roo Management Policy and Science:Fails to monitor family structure (spatial population monitoring)
-Fails to deal with size reduction, fertility increases probably related to culls etc
-Fails to look at behaviour; notably breeding limitations exerted through incest avoidance/dominance and separate male/female territory
-Underestimates immigration (See Zenger et al)
-Fails to use DNA monitoring to help in the above
-Seems excessively presumptive and mechanistic.

NOTES

[1] Zenger et al DNA study 2003: (Heredity (2003) 91, 153–162. doi:10.1038/sj.hdy.6800293, K R Zenger, M D B Eldridge and D W Cooper, “Intraspecific variation, sex-biased dispersal and phylogeography of the eastern grey kangaroo (Macropus giganteus).”
http://www.nature.com/hdy/journal/v91/n2/full/6800293a.html)

[2] Harvesting impact literature: Many of these studies arise from fish stocks. Articles quoting studies for kangaroos tend to quote from the same very small amount of literature and to draw equivocal conclusions, frequently paraphrasing each other. Peter T. Hale, “Genetic effects of kangaroo harvesting”, Australian Mammalogy 26:75-86 (2004)http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.319.7936&rep=rep1&type=pdf seems to be the main work cited, but relies on studies which Fletcher’s Phd calls into question, has little to say about eastern grey kangaroos but seems to infer that they have similar rates of starvation attributed to red kangaroos.

In Review of Scientific Literature Relevant to the Commercial Harvest Management of Kangaroos (2011) http://www.environment.nsw.gov.au/resources/nature/110641Kangaroolitreview.pdf , pp.27-28, after flagging the potential impact of harvesting on kangaroos, the study concludes with a mere opinion that the impact of size and other harvesting selection on kangaroos probably would not be great, on the assumption that the harvested populations are not isolated. This is pretty much as Hale’s study (above) concludes. However we know that the harvested populations in northern NSW and Queensland are genetically isolated and impoverished according to Zenger et all (2003) cited above. Furthermore, the review showed it was aware of Zenger et al.

“The last two reviews concluded that there was no evidence, or potential, that commercial harvesting could alter the genetic structure of kangaroo populations at current harvesting levels (Olsen and
Braysher 2000, Olsen and Low 2006). It was perceived that kangaroo populations would have to be
reduced to very low levels for genetic impacts to become significant (Olsen and Braysher 2000).
Moreover, at the time of the last review, it was concluded that there was an absence of theoretical,
empirical and modelled evidence of genetic impacts at current levels of harvesting” (Olsen and Low
2006, p50) and there were few, if any,examples of harvest‐induced body size selection in terrestrial
vertebrates. While there have not been any studies specifically investigating the potential genetic
impacts of harvesting kangaroos since the last review, there have been a large number of original
research and review papers addressing this question in a range of other vertebrate species, highlighting the perception that the potential genetic consequences of harvesting may be significant.

The human harvest of wild animals is generally not a random process, with harvesters often selecting phenotypically desirable animals, e.g. those with a large body size or elaborate weaponry, such as antlers. This therefore has the potential to impose selective pressure on wild populations, which may result in an alteration to population structure by reducing the frequency of these
desirable phenotypes and/or an overall loss of genetic variation (Allendorf et al. 2008).
Allendorf and Hard (2009) have termed this process “unnatural selection”, which is defined as undesirable changes in an exploited population due to selection against desirable phenotypes. Cited examples of the
effects of selective harvesting on desirable phenotypes include an increase in the number of tuskless elephants (Loxodonta africana) in South Luanga National Park, Zambia, and a decrease in horn size of bighorn sheep (Ovis canadensis) because of trophy hunting (reviewed in Allendrof and Hard 2009). In the case of bighorn sheep, the observed genotypic and phenotypic effects resulted from selective harvesting of young males with rapidly growing horns a trait linked with high reproductive
success) before they reached an age where they could achieve high reproductive success (Coltman
et al. 2003). This study highlights the importance of understanding age-specific trait size, rather
than trait size per se.
A recent review by Mysterud (2011) discusses the relative importance of various biotic and abiotic
factors that determine the potential for selective pressure from harvesting. In particular, Mysterud highlights the importance of assessing selective harvesting within the context of management regulations, hunting methods, animal trait variance, behaviour and abundance. Mysterud argues that in many cultures large mammal harvesting is not expected to produce strong directional
selection in trait size.

Although many of the factors discussed are of greater relevance to traditional sport hunting, this review highlights the importance of a number of factors relevant to the commercial harvesting of kangaroos in Australia.

There is certainly evidence for selective harvesting of larger/older animals within kangaroo populations, primarily because the economic performance of kangaroo harvesting enterprises is highly sensitive to variations in average carcase weight (Stayner 2007). Between 1997 and 2009 the total harvest in NSW comprised between 70 and 89% males. In the case of wallaroos, the
commercial take is even more strongly biased towards males (almost 90%), because females rarely
reach the minimum size dictated by licence and market conditions (Payne 2011). Despite the preference for larger males, it was reported that harvesters target a range of sizes above the minimum, especially when densities are reduced and there are fewer target animals (Payne 2011).
There average weight of harvested animals supports this assertion [(Table 2)].
As reported in the last review (Olsen and Low 2006), studies on the potential effects of size-selective harvesting in kangaroos concluded that although there was potential for genetic consequences of
harvesting within a closed population (Tenhumberg et al. 2004), the degree of mobility and
geographic range of genetic populations of kangaroos would be sufficient to ensure that any localised effects could be countered by immigration (Hale 2004). So, the question remains: does the recent literature on this topic provide any basis for changing the previous conclusions?

Probably not.

In the big horn sheep example referred to above, the extent of selective harvesting pressure was probably much stronger than occurs in kangaroo populations. In addition, the population was small, isolated and had restricted potential for immigration (Coltman et al. 2003), thereby exhibiting characteristics akin to a closed population. As such, this probably represents a more extreme example, where prevailing management and biological factors combined to create strong selective
pressure.”
Penny Olsen and Tim Low, “Situation Analysis Report, Update on Current State of Scientific Knowledge on Kangaroos in the Environment, Including Ecological and Economic Impact and Effect of Culling,” School of Botany and Zoology, Australian National University, Canberra, ACT and 6 Henry Street, Chapel Hill, Queensland, Prepared for the Kangaroo Management Advisory Panel, March 2006

Proceedings of the 2010 RSPCA Australia Scientific Seminar: Convergence or conflict: animal welfare in wildlife management and conservation, Tuesday 23 February 2010, CSIRO Discovery Centre, Canberra https://www.rspca.org.au/sites/default/files/website/The-facts/Science/Scientific-Seminar/2010/SciSem2010-Proceedings.pdf
[3] Family structure/westermarck/incest avoidance/endogamy/exogamy: Sheila Newman, Demography, Territory, Law: Rules of animal and human populations, Countershock Press, 2013, Chapter 3, “CHAPTER 3: The urge to disperse: Why children don’t usually marry their parents.” (Available amazon.com) Examples of incest avoidance citations within:

“Several studies have shown that maternal relatives avoid mating with one another (rhesus macaques: Smith, 1995; red colobus, Procolobus badius temminckii: Starin, 2001; Japanese macaques: Takahata et al., 2002; and see for review: Moore, 1993; van Noordwijk and van Schaik, 2004), 88 but less is known concerning patterns of inbreeding avoidance between paternal relatives (but see Alberts, 1999). In this study, we showed that the probability of paternity by a dominant male decreased when he was related to the dam at R = .5 (the highest possible relatedness coefficient in our study). Smith (1995) showed in rhesus macaques that the intensity of inbreeding avoidance was directly correlated with the closeness of kinship, as in the mandrills studied here. ”

Marie Charpentier, Patricia Peignot, Martine Hossaert-McKey, Olivier Gimenez, Joanna M. Setchell, and E. Jean Wickings., 2005. “Constraints on control: factors influencing reproductive success in male mandrills (Mandrillus sphinx).” Behavioral Ecology 16:614–623]

More reference examples on incest avoidance in multiple species:

Hoier, S., 2003. “Father absence and the age of menarch, A test of four evolutionary models,” Human Nature, Vol. 14, No. 3, pp. 209–233, Walter de Gruyter, Inc., New York.
Cockburn A, Osmond HL, Mulder RA, Green DJ, Douvle MC, 2003. Divorce, dispersal and incest avoidance in the cooperatively breeding superb fairy-wren Malurus cyaneus. J Anim Ecol 185 72:189–202;
Griffin AS, Pemberton JM, Brotherton PNM, McIlrath G, Gaynor D, Kansky R, O’Riain J, Clutton-Brock TH, 2003. A genetic analysis of breeding success in the cooperative meerkat (Suricata suricatta). Behav Ecol 14:472–480;
Mateo JM, 2003. Kin recognition in ground squirrels and other rodents. J Mammal 84:1163–1181;
Pusey A, Wolf M, 1996. Inbreeding avoidance in animals. Trends Ecol Evol 11:201–206;
Stow AJ, Sunnucks P, 2004. Inbreeding avoidance in Cunningham’s skinks (Egernia cunninghami) in natural and fragmented habitat. Mol Ecol 13:443–447;
Yu XD, Sun RY, Fang JM, 2004. Effect of kinship on social behaviors in Brandt’s voles (Microtus brandti). J Ethol 22:17–22.

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