POTENTIAL STUDENT PROJECTS
We have a number of projects available and are always happy to talk to prospective
students about their own ideas. The list below is not comprehensive, but will give you
an idea of the type of projects we can offer. Also visit our website at:
www.freshwaterfishgroup.com
Help to save Australia’s newest (and possibly rarest) freshwater fish
The little pygmy perch (Nannoperca pygmaea) was formally named in the journal
Zootaxa in April, 2013. This fish has been found to date from only one river, where it
occurs in sympatry with the closely related and more widespread western pygmy
perch, Nannoperca vittata. If we are to effectively conserve the little pygmy perch,
we need to know more about its distribution and life cycle. In particular, information
about its breeding sites and spawning behavior are essential.
In this project, you will be providing answers to questions of vital conservation
significance:
 What is the distributional range of the species?
 When and where does it breed?
 Does it have spawning or feeding migrations?
 If so, what triggers these migrations?
For more information contact Stephen Beatty (s.beatty@murdoch.edu.au)
What determines the distribution of freshwater fish in the southwest?
The south-west of Western Australia has a unique and endangered freshwater fish
fauna. To conserve these fishes we need to understand what environmental factors
determine their distribution and how these may change with impacts such as climate
change. We have a large database of fish captures throughout the south-west and this
project will match this database to geographical and environmental information,
available from government agencies and through field surveys. The aim of the project
is to identify critical environmental factors influencing species distributions. It will
suit someone with GIS skills and an interest in making an important contribution to
the conservation of the unique freshwater fishes of Western Australia.
For more information contact Stephen Beatty (s.beatty@murdoch.edu.au)
How well do fish swim?
River barriers, such as dams and weirs, are a major threat to the unique freshwater
fish fauna of Western Australia, because they prevent feeding and spawning
migrations and may lead to disconnected populations. Fishways are structures which
may enable fishes to negotiate these barriers and we are involved in a number of
projects to design and construct fishways throughout the state. Effective fishway
design, however, requires knowledge of the swimming performance of the target
fishes and this information is currently very limited for native freshwater fishes in
Western Australia.
This study will use a swim tunnel, recently installed in our laboratory, to measure the
swimming performance of freshwater fishes and relate swimming performance to
parameters such as fish age, size and sex, water temperature and parasitic infection.
The data that are obtained will have immediate applications because they will be
related to water flow measurements from current fishways and used to design
improved fishways in the future.
For more information contact Stephen Beatty (s.beatty@murdoch.edu.au)
Bull Sharks: recruitment and movement patterns in the Kimberley
The bull shark (Carcharhinus leucas) is considered to be one of the world’s most
dangerous species. This project will compare catch data of the juveniles of the species
over the last few years in the Fitzroy River and implement an acoustic tracking study
to determine the movement patterns (short term and long term) and habitat use. The
project will suit a candidate that likes field work in remote areas and will involve
Indigenous Ranger groups.
For more information contact David Morgan (d.morgan@murdoch.edu.au)
Freshwater Crocodiles: habitat use in small riverine pools of the
Kimberley
The freshwater crocodile (Crocodylus johnstoni) is an iconic species in the rivers of
northern Australia. There is much concern that freshwater crocodiles will be severely
impacted in the Kimberley by the invasion of the introduced cane toad (Bufo
marinus). This project will assess the habitat ulitisation, home range and movement
patterns of this large freshwater predator in pools of the Fitzroy River. This will be
achieved through acoustic tracking and mark-recapture of the species. The project
will suit a candidate that likes field work in remote areas and will involve Indigenous
Ranger groups.
For more information contact David Morgan (d.morgan@murdoch.edu.au)
Dwarf Sawfish: recruitment and movement patterns in the
Kimberley
The dwarf sawfish (Pristis clavata) is critically endangered (IUCN) and is considered
to be one of the world’s rarest species. The Kimberley is a hotspot for the species, yet
very little is known about its biology. The candidate will be assisting in developing an
acoustic tracking (passive) study in the Fitzroy River estuary and King Sound to
examine the movement patterns and habitat usage of the species, and will also
determine likely conservation threats. The project will suit a candidate that likes field
work in remote areas and will involve Indigenous Ranger groups.
For more information contact David Morgan (d.morgan@murdoch.edu.au)
Is Australia free of Edwardsiella ictaluri?
Edwarsiella ictaluri is a bacterium which causes significant economic losses in
aquaculture catfish industries in the USA and south-east Asia. It has been detected in
exotic aquarium fish species in Australia, but there has as yet been no survey of wild
fishes.
The aim of this project is to investigate the prevalence of E. ictaluri in freshwater
catfish across northern Australia. You will work with an epidemiologist to determine
an appropriate sampling program and link with catfish projects in the Kimberley,
Northern Territory and north Queensland to obtain tissue samples and culture for
bacteria. The data that are obtained will inform Australia’s disease freedom status for
this important bacterial disease of freshwater fishes.
For more information contact Susan Kueh (s.kueh@murdoch.edu.au)
Study the healing process in fish gills after toxic insults
Water has 30,000x less oxygen than air. Hence, fast swimming fish are very
susceptible to gill damage. Algae blooms may produce substances toxic to tissues
including gills. Algae blooms can be very transient, with clinical signs presenting in
affected fish only 1-2days after the blooms have been washed away by currents or
tides. This often makes the diagnosis of the cause of gill damage difficult without a
good understanding of how gills response and heal in the period following toxic
insults. Surprisingly while many published papers report on the gill damage caused by
various toxic chemicals, none could be found describing the healing process that
follows. The question remains: do fish gills response to toxic damage much like lung
tissues in mammals and birds?
This study will require you to:
• Design live fish experiments to study the healing process in fish gills post
exposure to toxic compounds
• Carry out histopathological evaluation of gills sampled over time
• Undertake ultrastructural evaluation using electron microscopy
For more information contact Susan Kueh (s.kueh@murdoch.edu.au)
Evaluation of in-feed essentials oils as a control for ‘Big Belly’, a gut
bacterial disease of Lates calcarifer (barramundi)
‘Big Belly’ (aka Pot Belly) is a significant bacterial disease of barramundi fry at the
hatchery level in Southeast Asia. ‘Big Belly’ can cause mortalities of 80 to 100%. It is
caused by intracellular coccobacilli and is difficult to treat. The disease may persist as
a chronic gut infection in grow-out barramundi.
In this study, we are interested in incorporating the essential oils extracted from
garlic, ginger, clove or cinnamon into feed as a potential means of controlling ‘Big
Belly’. Similar trials carried out in rainbow trout and tilapia have shown beneficial
effects including better resistance to disease.
You will be involved in the following:
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Field & laboratory trials based in Singapore
Design of experimental field trials to evaluate in-feed essential oils
Evaluate the effects of these supplements via examination of test versus
control fish tissues
Laboratory challenge trials against pathogens
For more information contact Susan Kueh (s.kueh@murdoch.edu.au)
How many freshwater mussels do we have in south-western
Australia?
Only one species of freshwater mussel, Carter’s freshwater mussel or Westralunio
carteri, is thought to occur in the south-west of Western Australia. A recently
completed PhD project by Dr Michael Klunzinger found that W. carteri has
undergone a massive reduction in range over the last 50 years, principally because of
salinization and drying of rivers. The same project found some tantalizing evidence
that certain populations of these mussels are genetically differentiated, to the extent
that they may not belong to the same species.
The aim of this study is to use molecular genetic and morphological analyses to
determine whether there are one or more species of freshwater mussels in the southwest of Western Australia. Answering this question will have important consequences
for conservation management, because it will affect both the conservation status and
future management plans for freshwater mussels in the region.
For more information contact Alan Lymbery (a.lymbery@murdoch.edu.au)
Are mussels keystone species for freshwater ecosystems?
Mussels play important roles in the functioning of freshwater ecosystems throughout
the world, particularly because their filter feeding activities influence water chemistry
and clarity, and the amount and kind of suspended particles in the water. Nothing is
known, however, of the extent to which Carter’s freshwater mussel influences water
quality in Western Australian rivers.
Mussel densities can be very high ( 100 m-2) in pools which form over summer in
many of the ephemeral rivers in the south-west. These pools are important refuge sites
for native freshwater fishes and we hypothesise that mussels contribute to the survival
of fishes in the pools through their filter feeding activities, which may reduce algal
density, enhance water quality and prevent lethal deoxygenation. The aim of this
study is to test this hypothesis using a combination of field observations and
manipulation of mussel and fish densities in experimental ponds.
For more information contact Alan Lymbery (a.lymbery@murdoch.edu.au)
Are introduced parasites a threat to our native fishes?
Introduced fish species may impact native fishes directly, through predation and
competition, or indirectly, by bringing with them new diseases. We have recently
discovered in the south-west the exotic parasite Lernaea cyprinacea, which was
probably introduced with goldfish and carp. This parasite appears to be both more
prevalent and more virulent in native fish species than in its original host species.
Understanding why this is will help us to control them.
The principal aim of this project is to answer the following questions:
(1) Does the parasite infect native fishes more readily because of the fishes’
behaviour?
(2) Are native fishes less able than goldfish to mount an effective immune response?
(3) Do native fishes show a greater pathogenic reaction to the presence of the
parasite?
For more information contact Alan Lymbery (a.lymbery@murdoch.edu.au)