The Hunter and Biodiversity in Tasmania

The Hunter
and Biodiversity in Tasmania
The Hunter takes place on Tasmania’s
Central Plateau, where “One hundred and
sixty-five million years ago potent forces
had exploded, clashed, pushed the plateau
hundreds of metres into the sky.” [a, 14]
The story is about the hunt for the last
Tasmanian tiger, described in the novel as:
Fig 1. Paperbark woodlands and button
grass plains near Derwent Bridge, Central
Tasmania. Source: J. Stadler, 2010.
“that monster whose fabulous jaw gapes
120 degrees, the carnivorous marsupial
which had so confused the early explorers
— a ‘striped wolf’, ‘marsupial wolf.’” [a, 16]
Biodiversity
“Biodiversity”, or biological diversity, refers to variety in all forms of life—all plants and animals, their genes, and the ecosystems they
live in. [b] It is important because all living things are connected with each other. For example, humans depend on living things in the
environment for clean air to breathe, food to eat, and clean water to drink.
Biodiversity is one of the underlying themes in The Hunter, a Tasmanian film directed by David Nettheim in 2011 and based on Julia
Leigh’s 1999 novel about the hunt for the last Tasmanian Tiger. The film and the novel showcase problems that arise from loss of
species, loss of habitat, and contested ideas about land use. The story is set in the Central Plateau Conservation Area and much of
the film is shot just south of that area near Derwent Bridge and in the Florentine Valley.
In Tasmania, land clearing is widely considered to be the biggest threat to biodiversity [c, d]. Land clearing is performed to make
room for [d]:
•
•
•
•
•
pasture for livestock
land for cropping
plantations, or tree farms for growing soft and hard wood
dams
cities and towns
These activities are important for Tasmania’s economy. For example, in 1999, the year that The Hunter was written, Tasmania
produced [e]:
• 70% of Australia's decorative veneers
• 50% of Australian produced printing and writing paper
• 57% of Australian newspaper.
Land clearing is controversial because it:
• destroys native vegetation and forests containing centuries-old trees—such as myrtle, sassafras, leatherwood and celery-top
pine [f]
• destroys habitat for native birds and wildlife that die, as a result, from exposure, starvation, and stress [g]
• causes water that was once used by plants to rise through the soil bringing salt deposits with it. The salt water makes the
soil less productive for farming, and taints river and water supplies. Damage from salt water also has the potential to affect
foundations, parks, gardens, roads, and buildings in towns and cities. [g]
• emits greenhouse gases into the atmosphere through bulldozing, and rotting and burning bush [g]
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Fig 2. A banner protesting
deforestation. Source: Florentine
Protection Society, photograph
by Alan Lesheim.
The Hunter dramatises heated
debates about forest management
and logging in an economically
and ecologically vulnerable region
of Tasmania and the film includes
images of an actual forest
blockade with protesters’ banners
stating “Save the Upper
Florentine.”
Biodiversity and the thylacine
The Hunter features one of the most famous extinct species in the world—the
Tasmanian tiger, or thylacine. The world’s last thylacine was captured and sold to
Hobart’s Beaumaris Zoo in 1933, and died on 7 September 1936. It was also added to
the list of protected wildlife in 1936 and declared extinct by international standards in
1986. It is the only mammal to have become extinct in Tasmania since European
settlement. [h]
The thylacine looked like large, long, yellow or greyish dog with stripes and a big head. It
had short ears, short fur, and a stiff tail. Its scientific name, Thylacinus cynocephalus,
means “pouched dog with a wolf’s head”. [h, i] Contrary to any of its names, it was not a
tiger, dog or wolf, but a marsupial.
Although known as the “Tasmanian” tiger, thylacines once lived throughout mainland
Australia and New Guinea. It is believed that both the Tasmanian tiger, and the
Tasmanian devil, became isolated on Tasmania after a land bridge to mainland Australia
was flooded at least 10,000 years ago. [j] Tasmanian tigers ranged from Kakadu and the
Pilbara down to Tasmania (as evident in Aboriginal rock art), but their range later shrunk
to the Tasmanian highlands.
Thylacine facts:
• A fully-grown Tasmanian tiger was about
160-180cm long from head to tail, and weighed
30kg. [h, j]
Fig 3. Thylacines, 1906.
Source: Smithsonian
Institution Archives.
• It wasn’t really a tiger, but people thought it
looked like one because it had 13-20 stripes
from the base of its tail to its shoulders. [h]
• The oldest thylacine bones found in Australia
came from Riversleigh World Heritage fossil site
in north-west Queensland, and are 30 million
years old. At least seven different species have
been found at this site—from the size of a small
cat, to the size of a fox. [i]
• The thylacine ate only meat, and was the
world’s largest meat-eating marsupial. [h] The
largest meat-eating marsupial is now the
Tasmanian devil.
• It had an unusually large jaw, which it could
open very wide. Despite this, its main source of food was likely wallabies, or other
small animals like possums, and birds. [j, n] Recent research has shown that it
was likely too weak to kill sheep, as it was once accused of doing. [l]
• It had 46 teeth [i]—4 more than an adult dog and 14 more than an adult human.
• Both male and female thylacines had pouches—females had a backward facing
pouch for carrying young, while males had a pouch to protect their reproductive
organs. [i]
• Thylacine pups were probably born in litters of 3 or 4, and had a gestation period
of one month, followed by another 3-4 months in their mother’s pouch. [n]
• Thylacines lived up to 9 years in captivity, but they probably only lived 5-7 years in
the wild. [n]
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Reasons for thylacine extinction:
• Many scientists believe that the thylacine became extinct on mainland Australia
because of dingoes. According to the “niche overlap hypothesis,” the thylacine
and dingo had similar hunting techniques and therefore competed for the same
food. Recently, scientists found that unlike the dingo, with its locked elbows
designed for outrunning its prey, thylacines had flexible elbows suggesting that
they ambushed their prey. [o]
The reasons given for the
extinction of the thylacine in The
Hunter are:
“a combination of habitat
fragmentation, competition with
wild dogs, disease, and intensive
hunting had forced their
demise.” [a, 37]
• Tasmanian tigers, like Tasmanian devils, are known to have poor ‘genetic
diversity’ [k], which is thought to be due to their separation from mainland
Australia. [p] Being related genetically makes them prone to effects of inbreeding
such as disease, reduced fertility, lower birth rates, higher infant mortality, and
general inability to adapt to changes in their environment.
• Using models that simulate the effects of bounty hunting, habitat and loss of prey,
scientists have shown that it was ultimately humans that were the cause of the
thylacine’s demise. [m] Thylacines were thought to be killing livestock, especially
sheep, in an environment where wool was quickly replacing whaling and sealing
as Australia’s main export. [q] In 1830, Van Diemen’s Land Co. introduced
thylacine bounties. From 1888-1909 the Tasmanian government paid for 2,184
bounties. By 1910, thylacines were considered rare and sought by zoos around
the world. [n]
Cloning/bioethics and the Tasmanian tiger
In the film The Hunter, the Tasmanian tiger is hunted because it is believed to have toxic
venom in its bite that can paralyse its prey. The notion that the Tasmanian tiger had a
venomous bite is entirely fictional, and there is no evidence to support this. On the other
hand, Tasmania is home to the Tasmanian Tiger snake, which is known for producing
large amounts of highly toxic venom. [t]
Martin David’s job in the film is to kill the Tasmanian tiger so that he can get a sample of
its DNA to recreate the fictitious biotoxin. In reality, he probably wouldn’t need to kill the
Tasmanian tiger to get a sample of its DNA. Scientists have already
cloned other animals from blood [aa] and skin [z] samples. If the
thylacine was captured alive, the genetic information needed to identify
the toxin gene could come from a blood, skin, or possibly hair [bb, cc]
sample (with follicles).
The Hunter also contains
speculation about cloning the
thylacine to develop biological
weapons:
“By studying one hair from a
museum’s stuffed pup, the
developers of biological weapons
were able to model a genetic
picture of the thylacine, a picture
so beautiful, so heavenly, that it
was declared capable of winning a
thousand wars. Whether it will be a
virus or an antidote, M does not
know, cannot know and does not
want to know, but there is no
question the race is on to harvest
the beast. Hair, blood, ovary,
foetus — each one more
potent.” [a, 40]
Cloning the thylacine was once an active program of the Australian
Museum but it was unsuccessful. The “Thylacine Cloning Project”
relied on using cells taken from a thylacine pup that have been
preserved for more than 100 years. [v] When an animal dies so do its
cells and the DNA inside them, and so this makes it difficult for
scientists to get all the information they need for cloning using
preserved thylacines. [u]
Cloning of the Tasmanian tiger is controversial because [w]:
• Some people think that we should be focusing our money and
efforts on protecting the animals we have, including
endangered species, and preserving their habitat instead.
• Some people believe that cloning a species sends the wrong
message about extinct animals (that they can be brought back
to life).
• It is also unclear whether a recreated Tasmanian tiger could
survive in what is left of its remaining habitat, or what effect it
would have on that habitat. It is likely that any successful
Tasmanian tiger clone would have to live in captivity.
Fig 4. A preserved
Thylacine pup
(Thylacinus
cynocephalus).
Source: Museum
Victoria
If researchers succeed in cloning the Tasmanian tiger, the Tasmanian
devil is thought to make a good surrogate mother for the embryo. See
http://www.biotechnologyonline.gov.au/popups/int_thylacinecloning.html for an
interactive demonstration of the potential thylacine cloning process.
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Martin sets traps to snare the
elusive thylacine, but he attracts
only wallabies, Tasmanian devils
and a spotted tiger quoll:
Biodiversity and the Tasmanian devil
In The Hunter, Martin David poses as a Tasmanian devil researcher. Tasmanian devils are
the thylacine’s closest genetic relative, along with the numbat.
“The track they are on was cut by
old trappers. In his study of the
area he’d read that a hundred
years ago the same ground would
have been regularly used by men
carrying up to seventy pounds of
wallaby and possum pelts across
their shoulders. Tiger pelts, too, or
carcasses: once upon a time. Up
on the plateau more tigers were
caught than anywhere else on the
island.” [a, 15]
Fig 4. Tasmanian Devil.
Source: Gerry Pearce,
Australian-wildlife.com
The Tasmanian devil is about the size of a small dog. It is mostly black with the odd
white patch on its chest, shoulder or rump. It has a stocky frame with longer front legs
than back. They can weigh up to 13kg. [r, s] Its scientific name, Sarcophilus harrisii,
means “Harris’s meat lover”—it was George Harris who wrote the first published
description of the Tasmanian devil in 1807.
Tasmanian devils are susceptible to Devil Facial Tumour disease, which is a
contagious cancer that spreads like an infection and is always fatal. The cancer
hides from the Tasmanian devil immune system so it does not recognise the
cancerous cells as foreign and reject them. [x, y] So far, the disease has killed
84% of the Tasmanian Devil population and they are currently listed as an
endangered species. [r, x] In an effort to start a cancer-free refuge of wild
Tasmanian devils, a group of 15 of them was introduced in 2013 to Maria
Island, off the east coast of Tasmania. [x]
Tasmanian devil facts:
• The Tasmanian devil was likely given its name because of its spinechilling screeches and black colour. [s]
• Since extinction of the thylacine, Tasmanian devils are now the largest
carnivorous marsupial in the world. [s]
Fig 5. Tasmanian Devil Species
Occurrence Map. Source: Atlas of Living
Australia, http://bie.ala.org.au/species/
Sarcophilus+harrisii
The Hunter invites us to think about biodiversity issues including loss of habitat,
extinction, land use values, and the possibilities that scientific advances in
genetic engineering and biological warfare might bring in the future.
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References for The Hunter and Biodiversity in Tasmania
[a] Julia Leigh (1999). The Hunter. Penguin: Ringwood, Vic.
[b] State of the Environment, Tasmania (2006), “Introduction”, http://soer.justice.tas.gov.au/2003/bio/4/
index.php
[c] State of the Environment, Tasmania (2006), “Land Clearance - At a Glance”, http://
soer.justice.tas.gov.au/2003/bio/4/issue/41/ataglance.php
[d] State of the Environment, Tasmania (2005), “Land Clearing in Tasmania”, http://www.wwf.org.au/
news_resources/archives/landclearing/landclearing_in_tasmania/
[e] State of the Environment, Tasmania (2006), “Native Forests - At a Glance”, http://
soer.justice.tas.gov.au/2003/bio/4/issue/58/ataglance.php
[f] Richard Flanagan (2007), “Out of Control: The Tragedy of Tasmania’s Forests”, The Monthly, http://
www.themonthly.com.au/monthly-essays-richard-flanagan-out-control-tragedy-tasmania-s-forests-512
[g] Bush Heritage (2013), “Land Clearing and its Impacts”, http://www.bushheritage.org.au/
natural_world/natural_world_land_clearing
Other links for The Hunter
and Biodiversity in
Tasmania
Video of the last Tasmanian tiger: http://
www.youtube.com/watch?
v=6vqCCI1ZF7o
Threatened species are now protected
under the Environment Protection and
Biodiversity Conservation Act 1999 (EPBC
Act): http://www.environment.gov.au/
resource/epbc-act-frequently-askedquestions
The Thylacine Museum: A Natural History
of the Tasmanian Tiger:
http://www.naturalworlds.org/thylacine/
[h] Department of Primary Industries, Parks, Water and Environment, Tasmania (2013), “Tasmanian
Tiger”, http://dpipwe.tas.gov.au/wildlife-management/animals-of-tasmania/mammals/carnivorousmarsupials-and-bandicoots/tasmanian-tiger
[i] Australian Museum (2013), “The Thylacine”, http://australianmuseum.net.au/The-Thylacine/
[j] Australian Government Department of Sustainability, Environment, Water, Population and
Communities (2013), Thylacinus Cynocephalus — Thylacine, http://www.environment.gov.au/cgi-bin/
sprat/public/publicspecies.pl?taxon_id=342
[k] Brandon Menzies, Marilyn Renfree, Thomas Heider, Frieder Mayer, Thomas B. Hildebrandt, and
Andrew J. Pask (2012), “Limited Genetic Diversity Preceded Extinction of the Tasmanian Tiger”, PLoS
ONE 7(4): e35433. doi:10.1371/journal.pone.0035433 http://www.plosone.org/article/info%3Adoi
%2F10.1371%2Fjournal.pone.0035433
[l] M.R.G. Attard, U. Chamoli, T.L. Ferrara, T.L. Rogers and S. Wroe (2011), “Skull Mechanics and
Implications for Feeding Behaviour in a Large Marsupial Carnivore Guild: The Thylacine, Tasmanian Devil
and Spotted-tailed Quoll”. Journal of Zoology, 31 August 2011 DOI: 10.1111/j.
1469-7998.2011.00844.x
[m] TA Prowse, CN Johnson, RC Lacy, CJ Bradshaw, JP Pollak, JM Watts, BW Brook (2013), “No Need
for Disease: Testing Extinction Hypotheses for the Thylacine using Multi-species Metamodels”, Journal
of Animal Ecology, Vol. 82, pp. 355–364.
[n] Tasmanian Parks & Wildlife Service (n.d.), “Thylacine, or Tasmanian Tiger, Thylacinus cynocephalus”,
http://www.parks.tas.gov.au/index.aspx?base=4765
[o] Borja Figueirido and Christine M. Janis (2011), “The Predatory Behaviour of the Thylacine: Tasmanian
Tiger or Marsupial Wolf?”, Biology Letters, Vol 7, pp. 937–940. doi:10.1098/rsbl.2011.0364
[p] The University of Melbourne (2012), “Limited Genetic Diversity of the Tasmanian Tiger Sheds Light on
Species’ Geographic Isolation”, http://newsroom.melbourne.edu/news/n-794
[q] Woolproducers Australia (n.d.), “About Wool”, http://www.woolproducers.com.au/about/trade/aboutwool/
[r] Australian Government Department of Sustainability, Environment, Water, Population and
Communities (2013), “Sarcophilus Harrisii — Tasmanian Devil”, http://www.environment.gov.au/cgi-bin/
sprat/public/publicspecies.pl?taxon_id=299
[s] Tasmanian Parks and Wildlife Service (2010), “Tasmanian Devil” fact sheet, http://
www.parks.tas.gov.au/file.aspx?id=6477
[t] Tasmanian Parks and Wildlife Service (2008), “Tiger Snake”, http://www.parks.tas.gov.au/index.aspx?
base=4750#
[u] Museum Victoria (n.d.), “Cloning the Thylacine: Fact or Fantasy?”, http://museumvictoria.com.au/
scidiscovery/dna/cloning.asp
[v] Judy Skatsoon (2005), “Thylacine Cloning Project Dumped”, ABCScience, http://www.abc.net.au/
science/articles/2005/02/15/1302459.htm
[w] Inter Press Service (2002), “The Tasmanian Tiger’s Controversial Comeback”, http://
www.ipsnews.net/2002/05/environment-the-tasmanian-tigers-controversial-comeback/
[x] Carl Zimmer (2013), “Raising Devils in Seclusion”, The New York TImes, http://www.nytimes.com/
2013/01/22/science/saving-tasmanian-devils-from-extinction.html?
pagewanted=2&nl=todaysheadlines&emc=edit_th_20130122&pagewanted=all&_r=0
[y] Nature (2013), “Vaccine Hope for Tasmanian Devil Tumour Disease”, http://www.nature.com/news/
vaccine-hope-for-tasmanian-devil-tumour-disease-1.12576
[z] National Human Genome Research Institute (2012), “Cloning”, http://www.genome.gov/25020028
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References for The Hunter and Biodiversity in Tasmania
[aa] Kamimura, S., Inoue, K., Ogonuki, N., Hirose, M., Oikawa, M., Yo, M., Ohara, O., Miyoshi, H. and
Ogura, A. (2013), “Mouse Cloning using a Drop of Peripheral Blood”, Biology of Reproduction, doi:
10.1095/ biolreprod.113.110098m, http://www.biolreprod.org/content/early/2013/06/25/biolreprod.
113.110098.full.pdf+html
[bb] livescience (2007), “Woolly Mammoth Hair Yields 'Fantastic' DNA”, http://www.livescience.com/
9530-woolly-mammoth-hair-yields-fantastic-dna.html
[cc] ScienceDaily (2008), “Woolly-Mammoth Genome Sequenced”, http://news.psu.edu/story/
181641/2008/11/19/scientists-sequence-woolly-mammoth-genome
This fact sheet and its links were last checked on 23 March 2014.
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