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Hydromys chrysogaster


I was searching for platypus, but instead, had my first encounter with Hydromys chrysogaster, commonly known as the water-rat. It is an Australian native, semi-aquatic rodent, and the indigenous name "Rakali" was adopted to foster a positive public attitude towards the species. They can weigh up to 1.3 kilograms - as big as a medium-sized platypus, and will eat just about anything they can get their nimble paws onto. Predation on Rakali mostly from hawks, eagles, snakes, quolls, large fish, and feral cats, although humans have been the greatest predators of all. Hydromys is a genus of rodents in the subfamily Murinae. Three species are endemic to New Guinea and nearby islands, and a fourth species, the Rakali, is found in Australia.


Spotted along the banks of the Severn River, Ballandean SEQ. It's a freshwater river, albeit a small one, but is very clean and abundant with food like yabbies and mussels. The steep banks are ideal for burrows, and are well protected by fallen trees, water grasses and other foliage. This is a quiet bushland area with native vegetation.


Not the clearest of pics, but I felt fortunate to see this animal hunting in broad daylight - they are mostly nocturnal. For several days I kept finding remnant mussel shells on the river banks, so I knew there was a predatory animal nearby - All I had to do was spot it! PS: An interesting article in one of the Sydney papers -

No species ID suggestions

QLD, Australia

Lat: -28.78, Long: 151.75

Spotted on Jul 25, 2017
Submitted on Dec 10, 2017

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