Sciences

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Sciences

Natural history - from animals to minerals, fossils to sea slugs. MV's scientists use the state's collections in important research.

Eastern Pygmy Possum

Author
by Phoebe Burns
Publish date
15 August 2014
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Phoebe is a University of Melbourne Masters student supervised by Dr. Kevin Rowe at MV. She is passionate about the unique mammal fauna of Australia.

Early one morning, while up in the Grampians searching for Smoky Mice (Pseudomys fumeus), I peeked inside an Elliot trap and was greeted by a delicate little face, huge ears, big bright eyes and fat, gently curled tail. Expecting to see the pointy face and straight, slender tail of an Agile Antechinus (Antechinus agilis), I hastily shut the trap, took a second to process the surprise and then beamed at my bemused volunteer. Another tentative peek in the trap confirmed it; I had trapped my first Eastern Pygmy Possum (EPP; Cercartetus nanus).

Eastern Pygmy Possum Eastern Pygmy Possum
Image: David Paul
Source: Museum Victoria
 

The EPP weighs in at a miniscule 15-38g1, yet still looks truly possum-like. It is one of seven possum species you could fit in your pocket, but is far from the smallest. The Little Pygmy Possum (Cercartetus lepidus) weighs only 6-10g and a full-grown Honey Possum (Tarsipes rostratus) can weigh as little as 5g1.

Like several other possum species, EPPs can obtain all required nutrients, including protein, from nectar and pollen alone.2 However they also eat insects, seeds and fruit, providing flexibility when few plants are flowering. Like the Fat-tailed Dunnart, the EPP stores fat at the base of its tail as a reserve for when food is scarce, and can go into torpor when keeping active is energetically too expensive.

Eastern Pygmy Possum Eastern Pygmy Possum
Image: David Paul
Source: Museum Victoria
 

As another of Australia’s amazing marsupial species, the female EPP gives birth to tiny eyeless, earless babies that suckle in her pouch for 30 days. Once the juveniles are too big for the pouch, they nest with their mother for another 30-35 days then head off alone.3 EPPs don’t build their own nests; they use whatever is available and change nest sites frequently. Researchers have found EPPs nesting in tree hollows, abandoned birds nests, burrows and natural collections of leaves and twigs in tree forks.3

Phoebe Burns with an adult female eastern pygmy possum Phoebe Burns with an adult female eastern pygmy possum (Cercartetus nanus) in the Grampians National Park.
Image: Kara Joshi
Source: Museum Victoria
 

 

Eastern Pygmy Possums are patchily distributed from the southeast corner of Queensland to the southeast tip of South Australia, Flinders and King Islands and throughout Tasmania. They are listed as near threatened in Victoria; at risk from predation by foxes and cats, competition with feral honeybees and increasing fire frequency.4 I consider myself so lucky to have encountered such a charming species and hope there are many more (pleasant) surprises in my traps for years to come.

References

1.         Menkhorst, P. & Knight, F. Field Guide to the Mammals of Australia. (Oxford University Press, 2011).

2.         Van Tets, I. G. & Hulbert, A. J. A Comparison of the Nitrogen Requirements of the Eastern Pygmy Possum, Cercartetus nanus, on a Pollen and on a Mealworm Diet. Physiological and Biochemical Zoology 72, 127–137 (1999).

3.         Ward, S. Life-History of the Eastern Pygmy-Possum, Cercartetus nanus (Burramyidae, Marsupialia), in South-Eastern Australia. Australian Journal of Zoology 38, 287 (1990).

4.         Harris, J. M. & Goldingay, R. L. Distribution, habitat and conservation status of the eastern pygmy-possum Cercartetus nanus in Victoria. Australian Mammalogy 27, 185–210 (2005).

Fat-tailed Dunnart

Author
by Phoebe Burns
Publish date
4 August 2014
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Phoebe is a University of Melbourne Masters student supervised by Dr. Kevin Rowe at MV. She is passionate about the unique mammal fauna of Australia.

There are 360 mammal species native to Australia. I'd challenge you to name them all, but even as a mammalogist (albeit early in my career) I'm still coming across species I haven't heard of. Even so, there are relatively common species I'm always surprised people don't know, for instance: what is a dunnart?

The Fat-tailed Dunnart (Sminthopsis crassicaudata) is one of 19 dunnart species. It is a small (10-20g) insect-eating dasyurid, which means that although it's mouse-sized, the dunnart is in the same family as the Tassie devil.

Fat-tailed Dunnart Fat-tailed Dunnart (Sminthopsis crassicaudata).
Image: David Paul
Source: Museum Victoria
 

The females give birth a mere 13 days after conception to 8-10 tiny immature young that are about one-eightieth the size of a new-born house mouse. The young suckle for around 65 days, moving from the pouch to their mother's back once they grow too large to fit.

Fat-tailed Dunnart Fat-tailed Dunnart scratching an itchy spot.
Image: David Paul
Source: Museum Victoria
 

Aptly named for their thick tails, the Fat-tailed Dunnart stores about 15 per cent of its body fat in the tail. This provides the animal with a back-up energy reserve during times when food is scarce. Torpor is another method the dunnart uses for dealing with an uncertain environment – when food availability becomes unpredictable they curl up, let their body temperature drop, and their metabolic rate slows. Torpor allows a dunnart to conserve energy when there is so little food around that they would burn more energy finding it than they could obtain eating it.

Fat-tailed Dunnart The thick tail of the Fat-tailed Dunnart contains fat stores that helps it survive in harsh conditions.
Image: David Paul
Source: Museum Victoria
 

Fat-tailed Dunnarts occupy a wide range of habitats across most of south and central Australia. They are one of a few native mammal species that can be kept as a pet in Victoria with a basic wildlife license, provided the animal is legally obtained and not taken from the wild.

If you want to learn more about our native fauna check out the Museum Victoria Field Guide app, and our sister apps for the rest of Australia.

Working at the museum is dead interesting

Author
by Meg
Publish date
21 July 2014
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We just took receipt of a beautiful Crested Pigeon, in excellent physical condition except for the fact that it was dead. But it will make a useful contribution to the museum’s body of research material. With the locality data carefully recorded, said pigeon was duly deposited in its new (temporary) home – our freezer – to await its final afterlife journey to the collection store.

Crested pigeon specimen. Crested pigeon specimen.
Image: Meg Lomax
Source: Museum Victoria
 

Temporary resting place - the Discovery Centre freezer. Temporary resting place - the Discovery Centre freezer.
Image: Meg Lomax
Source: Museum Victoria
 

As I closed the freezer door on our latest acquisition, I found myself feeling grateful, as an inhabitant of the twenty-first century, for the electricity we have to power our freezer in which we deposit our dead things, which we collect for exhibition and research purposes. In contemplating this luxury, I was reminded of a fun fact I learned during a meal at an old country pub while on holiday in Tasmania a couple of years ago – in colonial Australia, not only was there no electricity, but there was also no such thing as a town morgue, and so the remains of the recently departed were best stored in the coolest place in town, the local “house of public accommodation” – the pub. Yep, the bodies were in with the beer; the stiffs with the stout; the late with the lager; the passed with the pilsner, if you will. Encouraged by my interest, the enthusiastic new owner led me to the front room of the nineteenth century pub to be shown the very place where the bodies would have been laid out. I asked the new landlady if she was bothered at all by the history of her new business venture – she laughed and replied “not at all.” I asked her what she did before becoming a publican – she answered “I was a funeral director.” True story.  

Meanwhile, over the course of my internet wanderings on the topic of hotels-as-morgues, I came across a great little newspaper article about the dual function of Melbourne pubs, but then found myself back in Tassie when I unexpectedly tripped over this little nugget:

“The morgue motel: Plans to turn a ‘home’ of the dead into accommodation for the living”

Apparently, a local Tasmanian motel owner is currently in the process of converting the mortuary of the decommissioned Willow Court psychiatric hospital in the town of New Norfolk into somewhere for folk to sleep, although, unlike the original occupants, it is hoped that these guests wake up again.

Which brings me back to the Museum Victorian collections, for just yesterday I was photographing some mortician’s tools that were acquired from the former Sunbury Lunatic Asylum in Victoria. While the outbuildings of early Victorian asylums routinely included a morgue for the storage of the bodies of patients who had died within the asylum walls, it wasn’t until the proclamation of the Lunacy Act 1903 in Victoria that provision was made for the employment of a full-time pathologist to the Lunacy Department. The pathologist was tasked with conducting autopsies and undertaking pathological examinations to attempt to associate post-mortem lesions in the brain with ante-mortem symptoms. The development of this new clinical-pathological approach to psychiatric research was one of the outcomes of the increasing secularisation of medicine (and studies of the natural world more broadly), that emerged following the dissemination of the Darwinian theory of evolution towards the end of the nineteenth century.

A selection of objects from the former Sunbury Lunatic Asylum. A selection of objects from the former Sunbury Lunatic Asylum.
Image: Meg Lomax
Source: Museum Victoria
 

Unidentified mortician's tool, Caloola Training Centre (formerly Sunbury Lunatic Asylum). Unidentified mortician's tool, Caloola Training Centre (formerly Sunbury Lunatic Asylum).
Image: Meg Lomax
Source: Museum Victoria
 

Unidentified mortician's tool, Caloola Training Centre (formerly Sunbury Lunatic Asylum). Unidentified mortician's tool, Caloola Training Centre (formerly Sunbury Lunatic Asylum).
Image: Meg Lomax
Source: Museum Victoria
 

Like Willow Court in Tasmania, many of the pathology blocks associated with former Victorian psychiatric hospitals remain, although as yet none of them are offering bed and breakfast. One does, however, offer a fully-funded kinder program. Again, true story.

Australia’s biggest wildlife biobank

Author
by Alice
Publish date
27 June 2014
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We should all be giving each other a big round of high fives, as Museum Victoria has just been awarded a $500,000 Ian Potter Foundation 50th Anniversary Commemorative Grant for the development of Australia’s largest wildlife biobank! The new biobank—the animal equivalent of a seedbank—will enable us to store embryos, eggs and sperm from some of Australia’s most endangered animals. Based on super-cold liquid nitrogen, the biobank facility will store animal tissue samples at -150ºC, which is cold enough to preserve them for the long term.

Yellow-footed Antechinus Yellow-footed Antechinus captured for a blood sample then released.
Image: Museum Victoria
Source: Museum Victoria
 

  Dr Kevin Rowe sorting tissue samples in the field Dr Kevin Rowe sorting tissue samples in the field.
Image: Museum Victoria
Source: Museum Victoria
 

The proposed storage facilities sound like something straight out of Mr. Freeze’s lab: a custom-built airtight room equipped to house three liquid nitrogen dewar cryostorage vats, rather like giant vacuum flasks. Inside, vials containing tissue samples will be stored in the vapour above the liquid nitrogen. Kept in this manner, the samples will remain viable for more than 50 years.

  Staff at work in Laboratory. Staff at work in our Ancient DNA Laboratory.
Image: Museum Victoria
Source: Museum Victoria
 

Currently, our collection of over 40,000 tissue samples is limited to organs, skin, fur and feathers stored at -80ºC. These samples have been collected over the last 160 years and are priceless tools for scientific research into evolution, genetic relationships, species discrimination, and especially conservation. By enabling the long term storage of reproductive tissues, the newer, cooler biobank will enable us to realise the full potential of this collection and built on our ability to increase reproductive biology programs and genetic research.  

  Helena Gum Moth The apparent decline of Emperor Gum Moths and the closely related Helena Gum Moth have been a hot topic for scientists in recent years. Initiatives such as the biobank could largely benefit their survival.
Image: Patrick Honan
Source: Museum Victoria
 

Considering that our early natural history collectors could not have dreamed of the uses we would have found for their specimens over a century later; the Ian Potter Australian Wildlife Biobank offers new hope to endangered species, many of which may face extinction in the coming decades. With ever-increasing pressure from human impacts such as climate change and habitat loss on our native fauna, we envisage that the biobank will be a game changer for wildlife research, conservation and recovery. 

  Smoky Mouse The critically endangered Smoky Mouse is another native species that may benefit largely from this new technology.
Image: Museum Victoria
Source: Museum Victoria
 

The biobank is expected to be operating by late 2015.

Catalogue of cephalopods completed

Author
by Kate C
Publish date
4 June 2014
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Everyone loves a happy ending. And everyone loves octopuses. The recent completion of the third and final volume in the revised FAO Catalogue of Cephalopods of the World nails it on both fronts. 

Cephalopods of the World Volume 3 Cover of the new FAO Cephalopods of the World Volume 3.
Image: Emanuela D’Antoni
Source: Food and Agriculture Organization of the United Nations
 

This is a brilliant – and free – resource designed to assist people working in fisheries to identify the cephalopods that we humans are most aware of, namely the ones we've identified, that we eat, or can cause us harm. Volume 3: Octopods and Vampire Squids was co-authored by MV's Dr Mark Norman and Dr Julian Finn. They are also are two of the four series editors.

'Octopus’ berrima Spot the 'Octopus’ berrima in the sandy substrate! (The inverted commas signify that this species is provisionally placed in the genus Octopus.)
Image: Julian Finn
Source: Museum Victoria
 

Years of work and drawing from cephalopod researchers worldwide sees FAO Catalogue of Cephalopods of the World summarising descriptions of species for practical use by non-specialists. "We've distilled it down to diagnostic characters that will allow people on research or fishing vessels to identify species," says Julian. "It's a review of all the taxonomic work that's out there, for people who don't have immediate access to the literature." The species descriptions focus on traits that are easily measured, which is no mean feat for animals famous for changing their shape and form at will. Says Julian, "everything is based on characters that survive preservation and are consistent across members of a species, such as numbers of suckers, presence or absence of structures, and relative lengths of body components."

Julian and Mark also note that this project would not have been possible without significant financial and moral support from the Australian Biological Resources Study and the Hermon Slade Foundation. This allowed them to do the work on octopus taxonomy that was required for this new edition of the Catalogue. 

Argonauta argo The beautiful female Argonaut, or Argonauta argo.
Image: Julian Finn
Source: Museum Victoria
 

So, if you have an interest in, as Ze Frank calls them, 'the floppy floppy spiders of the sea', head to FAO and download a free copy of FAO Catalogue of Cephalopods of the World Volume 3 (PDF, 25.77Mb). And in case you need a reminder about why you love octopuses, here's a video showing how they can open jars from the inside (while we humans sometimes struggle to open them from the outside).

 

Eltham Copper Butterfly update

Author
by Kate Phillips
Publish date
13 May 2014
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Once thought extinct, the Eltham Copper Butterfly was rediscovered in 1986 in Eltham, in a small patch of bush that was going to be bulldozed to build houses. A campaign to save the butterfly’s habitat began and the local council, State government and local community raised the money to buy the land and make it a conservation reserve. Since then other sites have been reserved in other parts of Eltham, Greensborough, Castlemaine, Bendigo and Kiata.

Eltham Copper Butterfly Eltham Copper Butterfly (Paralucia pyrodiscus lucida) perched on Sweet Bursaria, Bursaria spinosa.
Image: Andrea Canzano
Source: Andrea Canzano
 

Over time, butterfly numbers in the Eltham reserves went down. People from the nearby houses would walk through the reserves, let their pets in and local kids couldn’t resist building cubby houses. Active trampling wasn’t the only problem. The reserves weren’t being grazed by native fauna or cleared by periodic burns any more. Vigorous native plants and weeds started to crowd out Sweet Bursaria, the butterfly's sole food. The habitat was no longer ideal for the larvae or butterflies which need patches of sunlight and clear flight-paths.

Eltham Copper larva with ants Eltham Copper larva being tended by Notoncus ants on a Sweet Bursaria bush. The Eltham Copper Butterfly can only live in habitats where this plant and these ants are present.
Image: Andrea Canzano
Source: Andrea Canzano
 

A couple of years ago I ventured out one cool September night to help with the larvae count at an Eltham reserve. While it was exciting to be in the bush at night we didn’t find a single larva where they had been numerous a few years earlier. Results like his made people realise that it was not enough to fence off reserves and expect the butterflies to flourish.

In 2012 the Friends of Eltham Copper Butterfly in partnership with Nillumbik Shire Council, Parks Victoria, Friends of Diosma Road, Friends of Woodridge Linear Reserve and Eltham East Primary School obtained a Communities for Nature grant to protect and enhance the habitat of the Eltham Copper Butterfly.

The habitat restoration involved skilled workers selectively weeding the reserves and planting more Sweet Bursaria, other butterfly-attracting native grasses and daisies to bring the vegetation back to an ideal mix for the Eltham Copper Butterfly.

And the result? Already, only 12 months later, there has been a significant increase in the number of Eltham Copper Butterflies recorded in the counts in this summer (2013-14). It is an encouraging start, and supports the idea that active management can make a decisive difference for an endangered species. Ongoing community involvement and education is the other vital component. This takes many forms from festivals, to butterfly-friendly garden courses, to education in the local schools.

Children and performer Eltham East Primary School children have planted a butterfly garden. Here they're learning about the Eltham Copper Butterfly.
Image: Alison Bayley
Source: Alison Bayley
 

So it looks hopeful for the Melbourne Eltham Copper populations but what about the butterfly in Central Victoria?

In 2009 there were only three known butterfly sites in Central Victoria but in the last five years a small team surveyed 3,000 hectares of public land looking for the right habitat features for the butterfly – a combination of enough Sweet Bursaria bushes in an open forest habitat. Having identified promising areas, they went back at the right time of year to see if they could find the adults. With great excitement they found seven new sites bringing the total in the region to ten.

Julie Whitfield in butterfly habitat Julie Whitfield, a leader in Eltham Copper butterfly conservation in Central Victoria, at a site where a colony of butterflies was found at Big Hill, Bendigo.
Image: Kate Phillips
Source: Museum Victoria
 

However at the same time these new butterfly colonies were being discovered, the risk of fire was brought into sharp focus and fuel reduction burns given greater priority.

Areas surrounding regional towns such as Castlemaine and Bendigo are set aside to be burnt each year. Many of these overlap with the newly-discovered Eltham Copper butterfly habitat. The fuel reduction burns are designed to be ‘thorough’. While this is seen as good fire risk management it endangers fire-sensitive species such as rare orchids; a fire in Eltham Copper Butterfly habitat could wipe out one of its populations. However when on-the-ground knowledge is used to guide fuel reduction burns, important habitat pockets can be excluded. It is not a case of conservation versus safety, but a balancing of the two needs.

Thanks to Andrea Canzano, Karen Borton, Anne Fitzpatrick and Julie Whitfield for their contributions to this post.

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