A Rakali is a large semi-aquatic rodent that is Australia’s
closest equivalent to an otter. They are
also commonly known as water rats, however this name bothers me as the animal
is clearly different from a rat.
Recently the Australian government decided that it was time to refer to
native Australian animals using aboriginal names and Rakali is the name used
for this animal by the people of the Murray-Darling river system. Rakali are present across most of Australia,
along both rivers and near the sea.
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| A Rakali (Photo: Mike Trennery, wettropics.gov.au) |
The Rakali is a major predator of crabs, particularly the
larger semi-terrestrial crabs such as the crabs that live in mangroves and
ghost crabs from sandy beaches. Seeing
a Rakali is very difficult as they are nocturnal and usually, they are detected
by footprints. In mangrove swamps near
Cairns, it is common for the mangrove forest floor to be almost covered with
foot prints, such is the scale of their activity. I suspect that their presence is one of the
reasons why mangrove crabs are mainly diurnal.
In turn Rakali might fall prey to large owls and pythons which also
visit mangrove swamps.
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| Front feet leave star-shaped prints and back feet, long prints with webbed toes |
Rakali also forage along beaches and I often see their
footprints in freshly reworked sand of creek mouths. Recently I found Rakali track on the beach at
Slade Point near Mackay and decided to follow them. The beach is almost a surf beach and is
exposed to strong winds and high wind waves.
At both ends of the beach there is a rocky headland and the Rakali
tracks ran along the high tide line from one headland to the other. As the tide peaked just after dark, the
Rakali must have traversed the beach whilst there were still traces of sunlight
in the sky. It is an audacious move for
such a small animal to travel a 850 m distance completely exposed. On the way across the beach, the Rakali
caught and ate a ghost crab.
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| Remains of the ghost crab |
Rakali reach approximately 1.3 kg in weight with a body length of nearly 40 cm so they are much larger than rats. They
are known to forage almost 3 km a night, however I don’t know if anyone has previously recorded them crossing of 850 m km of
exposed beach in a few minutes.
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| Dangerous, rogue waves often wash 10 m higher up than normal waves Photo of Lamberts Lookout in moonlight at 8:30 pm |
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| Lamberts Beach, which the Rakali crossed |
Rakali often drown in crab and yabbi pots, particularly in
freshwater. In South Australia, net crayfish pots have been banned due to the toll they take on turtles, Rakali and
Platypus. If you want to use yabbi traps, please check on the internet how to avoid wildlife kills. Rakali may not swim as often
in estuarine systems as they would be prone to attack by large fish and
crocodiles. Tides also expose their
prey, so they may not have need to dive.
