Chrissy was born on December 21 as part of a breeding program at the zoo and was undersized, weighing only 21 grams- about half the normal birth weight.
The zookeepers have been taking it turns to take the water rat home who similar to a newborn baby feeds three times during the night.
29-year-old Leanne Kelman who took over the night feeds last week said it was the most rewarding experience.
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READ NOW‘It is really interesting and all part of the experience of being a zookeeper,’ she said.
‘She is eating well and has got a lot of life in her.’
Chrissy was the first zoo animal Ms Kelman had taken off-site and said working with animals had been her passion for as long as she could remember.
At the 11-day mark last week, Chrissy weighed in at 42 grams but zookeepers said it was unlikely she would ever be released into the wild due to her small size but would become an ambassador for her species as part of the zoo’s education work.
The water rats were once common throughout Western Australia but are now considered extinct in some regions.
The zoo is working with the Australian Wildlife Conservancy and Whiteman Park to re-establish secure populations in areas where water rats have been almost wiped out. The aim is to restore an important small predator to the aquatic food chain.
Water rats are Australia’s largest native rodents. Apart from the platypus, they are the only amphibious land-based Australian mammal.
N For more zoo news, flip to page 3 to see which beloved zoo resident recently celebrated her 61st birthday.