Fishes of South Australia
The South Australian Museum has begun a large research program
to investigate the evolution and biodiversity of the state's
fish fauna.
It is timely with the start of a new century to review the
classification and status of our fishes by using modern molecular
genetic methods. These methods are based primarily on analysis
of genetic variation in DNA. DNA is the molecule that holds
all the genetic information necessary for an organism to live
and reproduce. By using the information about the evolutionary
history of the species that is contained in DNA, we will know
more accurately how many species there are, where they live,
and how they are related to one another. This information
is the starting point for managing fishes as a recreational
and commercial resource, and for ensuring their conservation.
How will the study of variation in DNA help us study our
fishes?
Although the research collection at the South Australian Museum
began in the late 1800's, it has only been in the last decade
or so that analysis of variation in DNA from the many different
species of fishes has become a practical reality. Specimens
collected in the past are generally not suitable for DNA analysis
because the DNA is degraded by the commonly used preservative
- formalin. This makes it necessary to collect at least one
specimen of each species of fish from South Australian waters
to provide DNA samples for the research program.
Once a DNA sample is available the scientists in the South
Australian Museumâs Evolutionary Biology Unit will determine
a genetic profile for some genes from each of the species.
These gene profiles comprise DNA sequences that are effectively
like the barcode used to identify goods purchased in supermarkets.
Because this information is digital it can be transferred
in electronic format between interested parties anywhere in
the world. We will also store digital images of the fish themselves,
these can be emailed to anyone requesting more information
of those species.
As an example of how this might be used, letâs say that a recreational
fisher in Ceduna has caught a very unusual fish. The fisher
could email a digital image to the museum specialist who then
might request that either the specimen or a scale (the latter
for DNA based identification) is sent to the museum for closer
examination. The museum specialist could then email other
images from the collection for the fisher to compare with
their specimen. Finally if the specimen proves to be of a
needed species the fisher may be asked to take the extra effort
required to preserve the specimen and donate it to the museumâs
research collection as people from South Australia have been
doing since the mid-1800âs.
What are the benefits of better classifications and better
tools for identification?
The more that the classification of organisms reflects their
shared evolutionary history the more we can predict their
biological properties, such as behaviour, ecology, and genetical
makeup. This can have the advantage of reducing the amount
of scientific investigation required for each individual species.
The availability of a DNA sequence database for all the species
in the State will make identification of species more reliable
and in some cases make identification of fish larvae or eggs
or trace samples such as individual scales either possible
or more rapid and reliable.
By keeping the specimens from which the DNA samples have been
taken (called voucher specimens) we will have a permanent
record also of the appearance of each specimen. Some of these
may turn out to be species that have not been described before.
In these cases our researchers can prepare formal descriptions
of the species for standard identification methods.
This collection is of international importance because scientists
in other parts of the world can borrow our voucher specimens
or DNA samples for their research programs. Likewise we will
be able to borrow specimens from their collection to help
us identify and compare the biology of the species in our
waters.
How can you help?
The number of fish species known from South Australian waters
is in excess of 727, so it will take some time to collect
the necessary samples. However, this task will be greatly
facilitated by the participation of the public. Recreational
fishing is an immensely popular pastime in South Australia.
Members of the public can assist by bringing or sending to
the museum, fresh or frozen specimens of any of the many species
that we have yet to collect. Remember that all current fishing
regulations and laws are to be observed.
From time to time we will conduct research projects on particular
fish species for a variety of reasons. At present we are interested
in a little known ray called the Magpie Fiddler. You
can read more about this project here.
A list of the species that are yet to be collected will be
posted shortly on this page.
Fisheries regulations must be adhered to when catching fish
even if they are handed into the museum. You can view the
current fisheries regulations by clicking
here.
Some of the South Australian National Parks & Wildlife
offices can receive fish specimens for the museum as they
have freezers available to store them. These offices are:
South East Mt Gambier: 8735 1112
KI - Murrays Lagoon: 8553 8233
Port Lincoln: 8682 6015
Ceduna: 8625 3144
For further information on this research program contact
Stephen Donnellan,
(82077479, Evolutionary Biology Unit)
Mark Hutchinson
(82077461, Vertebrate Department)