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ECX Corner: Goatfish
ECX cares about giving you a voice in the community to share and
spread your passions.
For this issue, we have marine biologist Louise Tosetto of Macquarie
University writing to us about her PhD on goatfish. What are they?
Where do we find them? Why are they so peculiarly named?
Goatfish are fish that live in coastal waters. They
are characterised by a pair of chemosensory
barbels (whiskas) which protrude from their chin
giving the appearance of a goatee. These barbels
are used to rummage through sand in search of
food. They are benthic carnivores which means
that they eat things like worms, crustaceans,
molluscs and other small invertebrates that are
buried in the bottom sediments of our oceans.
They are found in shallow waters of both tropical
and temperate areas. There are approximately
86 species worldwide. One of the most common
species in Sydney (and the one I am studying)
is the blue-striped goatfish. They are found
anywhere from 3 – 40m deep so if you’ve been out
diving or snorkelling in Sydney you’ve probably
seen these guys digging away in the sediment.
There are some reports suggesting that goatfish
are a possible indicator for the health of our
coastal ecosystems. Goatfish are continuously
rummaging through the bottom sediments
looking for food. While this is an effective way to
feed, it also releases food particles into the water
column making food available for other fish who
haven’t got the ability to dig through sediment.
Goatfish are also vital in aerating the bottom
sediments and circulating nutrients, much like
what farmers do when they plough their land.
This can increase the variety of animals living in
the sediment as well as have a positive impact on
the nearby algal communities.
Some goatfish have the capacity to rapidly change
their colour, just like chameleons. Blue-striped
goatfish can change from white to red (and back
again) in seconds depending on the time of day
or their activity. We often think that the reason
animals change colour is for camouflage but
researchers have found that colour change is
also essential in signalling and communication
in some chameleons and cuttlefish. There is
very little information about why fish can change
their colour and so, goatfish provide an excellent
species to study this phenomenon. It is possible
that goatfish change to red as a signal to attract
other fish for protection when they feed, or as a
warning sign to predators. It is exciting research
which will provide some insights into how
fish have adapted and evolved the capacity for
flexibility in colour.
We want to hear what
you’re interested in!
Email us at ecx@zikira.com and
our editors will be in touch.
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