Fun Water Rat Facts For Kids

Moumita Dutta
Oct 20, 2022 By Moumita Dutta
Originally Published on Aug 05, 2021
Edited by Jacob Fitzbright
Fact-checked by Tehil David
Fascinating water rat facts for everyone.
Age: 3-18
Read time: 9.1 Min

Water rats are semi-aquatic rodents, who are well adapted to their habitat, be it water or land. They are identified by their dark-brown rounded body and long tail, living in freshwater lakes, rivers, streams, riverbanks, burrows, and more. They belong to the family of ‘Muridae’ which has two distinguished sub-families namely ‘Murinae’ and ‘Sigmodontinae’. Muridae consists of seven hundred species scattered all over the continent of Australia, Africa, and Eurasia. The Hydromes, Crossomys, and Colomys are part of the ‘Murinae’ subfamilies which are the genera of water rats. Water rats (Hydromys Chrysogaster), a native rodent of Australia and discovered in 1804, came to be known as Australian water rats, which is also the largest amongst this species. These rats have water repellent fur and zero tolerance for cold therefore during the winter season instead of searching for prey in water they prefer staying in their burrows and preying on terrestrial animals. These genera are found all over the continent of Australia and other nearby islands, including New Guinea, especially in the eastern part of Australia, and other Australian territories including Queensland, north and south Australia, Victoria, Tasmania, and New South Wales.

If you want more information about water rats then keep reading this article.

For more interesting facts please check our article about the naked mole-rat and the kangaroo rat.

Water Rat Interesting Facts

What type of animal is a water rat?

These rats are semi-aquatic rodents from the Muridae family.

What class of animal does a water rat belong to?

These rats live in water as well as on land which exhibits Amphibious characteristics just like a Platypus. These rats and platypuses are Australia’s only two amphibious Mammals.

How many water rats are there in the world?

The population of these rats depends on the area in which they exist, although it is thought that they are abundant, yet they face threats in particular regions. Several orders have been passed for their protection but the exact number of this species is unspecified.

Where does a water rat live?

These genera of Hydromes, Crossomys, and Colomys are found on the Australian continent and its nearby island including New Guinea. They reside in Western Australia, especially the Rakali which is considered as the native species of Australia, South Australian regions, Queensland, and Victoria.

What is a water rat's habitat?

The habitats of this species may incorporate lakes, estuaries, rivers, and creeks because their main source of food is fish, small mammals, and aquatic insects. These genera of rats are very sensitive hence as the season becomes chilly they prefer staying in their burrows. They do not like living near residential areas, unlike common rats.

Who do water rats live with?

These rats prefer to be solitary, except for the breeding season.

How long does a Water rat live?

The approximate lifespan of these rats is between three and four years.

How do they reproduce?

The adult rats reproduce through copulation during their breeding season, which is around the end of winter until the beginning of spring. The adult rats gain maturity by the time they turn one year old and keep producing babies till they are three and a half years old, their gestation period is around thirty-four days and their average litter size is three or four pups. They are mostly solitary, but during the breeding season, they start socializing to search for a partner. Their litter size is limited, unlike the other species but the fertility rate is high, and this why they can populate an area very quickly. Rakali dug burrows near the banks camouflaging them amongst the wildlife vegetation to protect them and their offspring from potential predators.

What is their conservation status?

The conservation status appears the least concern but the species are facing threats due to many factors including environmental degradation, habitat loss, and hunting. Australian native species Water rat (Hydromys Chrysogaster) are being hunted for their soft fur. This species is prey on by the birds of prey, water birds, large fish, etc. Areas, where they face threat, may include the region of west Australian regions.

Water Rat Fun Facts

What do water rats look like?

Water Rats are fascinating to read.

Among all the water rats, the Australian water rat, also known as ‘Rakali’, is the largest rat found in the lakes, rivers, streams,  and freshwaters of Australia and New Guinea, including the regions of Queensland, Western Australia, South Australia, and the Northern Territory. These rats are specialized mammals, as they are extremely well adapted to life on land and in the water. The length of these water rats is approximately 9.1–14.6 in (23.1-37 cm) and their weight is 0.7–2.8 lb (0.3-1.2 kg), the water rat’s tail is sturdy and is approximately 9.5–13.6 in (24.1-34.5 cm).

Western water rats are 5.9 in (15 cm) and weigh 0.22 lb (0.09 kg), new Britain water rats are 11.4 in (29 cm) and weigh 1.53 lb(0.6 kg), both of these rats are from the genus Hydromes. They have water repellent fur that covers their body, which is thick, fuzzy and the color can be brown, black, or gray with orange and white fur. The water rat's tail is recognized for its length and the fact that the tip of their tail is white. Another distinguishing physical characteristic is their golden belly. Water rats have chiseled incisors and the outer coating is yellow, their eyes are small and their nose is blunt, also their head is not like every other rodent because it is flattened. They have thick whiskers and their ears are small, as well as having webbed hind feet like a platypus that helps them in swimming.

The water rats also undergo the process of shedding their fur, but the time this process takes may vary according to their sex. The male water rats shed during the summer and fall, while the female sheds during spring. It is not only their sex, but also factors like temperature, weight, and health condition that can influence their shedding, and this entire process is known as molting.

The ‘Earless Water rats’ of genus Crossomys as their name suggest have ears that are either imperceptible or non-existent, just like the Hydromes, the Crossomys moncktoni have webbed hind feet and prefer staying in water more than land. Their forefeet are short while their hind feet are long, so is their tail which is 8.3-10.2 in (21-25.9 cm), the body length of this species is approximately 6.9-7.9 in (17.5-20cm) and they weigh around 0.3 lb (0.1 kg). Just like the other species, they have water repellent dark grayish brown fur covering their body and a white belly. The African water rats, of genus Colomys, are 4.7 in (12 cm) making them the smallest water rats and they weigh around 0.1 lb (0.04 kg).

How cute are they?

Water rats are rodents, the opinion may vary as many people find them cute for their size, thick whiskers, and small eyes, but other people may not.

How do they communicate?

These rats are not completely nocturnal, they use pheromones and their whiskers to communicate.

How big is a water rat?

The size of rats may differ according to their species and genus, the Australian water rat is 9.1–14.6 in (23.1-37 cm). The biggest of them, the New Britain water rat, is approximately 11.4 in (29 cm), the western water rat is 5.9 in (15 cm), the earless water rat is 8.3-10.2 in (21-25.9 cm), the African water rat 4.7 in (12 cm). The common rat size is 12.5-18 in (32–46 cm) hence they are slightly smaller than common rats.

How fast can a water rat run?

These rats are fast-moving and speedy rodents on both land and in water, but their exact speed has not been estimated. Their average speed when running is twice the speed of swimming.

How much does a water rat weigh?

Their weight depends on the species, sex, and age of the rats. An adult rakali is 0.7-2.8 lb (0.3-1.2 kg) which is the largest of this species found in Australia, the New Britain water rats and western water rats are 1.53 lb (0.6 kg) and 0.22 lb (0.09 kg) respectively. The earless water rats are 0.3 lb (0.1 kg) while the African water rats are 0.1 lb (0.04 kg).

What are their male and female names of the species?

The male member of this species is known as a buck while the female is known as a doe.

What would you call a baby Water rat?

Baby water rats are known as pups or kittens, and the average litter size is four to five.

What do they eat?

These species are carnivores and they prey on various creatures including aquatic animals like small mammals, fish, reptiles, frogs, and crustaceans. Rodents are mostly nocturnal but these species are found actively searching for food during sunset and they have been spotted swimming and feeding during the early hours of the day. This rat has no tolerance for cold weather, hence during the winter season, it does not prefer swimming in the water, so it preys on the terrestrial wildlife and spends an ample amount of time in its comfortable burrow.

Are they dangerous?

These rats may not be physically intimidating but they are rodents, and rodents are proven to be dangerous as they can spread diseases.

Would they make a good pet?

Rats have frequently been pets because they are well-adapted to that habitat, but these rats are incompatible because they require a different habitat, they are found in the wild where there is permanent water as they are semi-aquatic. The requirement of freshwater, estuaries, riverbanks, streams, and creeks is hard to fulfill at home, hence it is better to leave them in the wild where they belong.

Did you know...

Water rats are non-existent on the Asian continent.

Water rats can safely consume cane toads which can prove fatal for other mammals.

‘Midden’ is the area where the water rats bring their leftover food, including bones and shells.

What does water rat mean?

These rats are semi-aquatic mammals just like platypuses, they spend the majority of their life in water, unlike common rats. The native rodent of Australia which was first reported was the Hydromys chrysogaste, their scientific name translates to ‘golden bellied rat’ due to their gold-colored belly, which came to be known as water rats or rabe. In 1990 they were given indigenous names to restore the reputation of this species in Australia and ‘Rakali’ was assigned as their common name, and these native species are very common across Australia.

Are Water rats different from rats?

Water rats differ from common rats in various aspects, for example, the genera of water rats are Hydromes, Crossomys, Colomys and the genus of rats is Rattus, apart from their genus, their physical characteristics are also different. Water rats have round bodies while rats have more of an elongated body. Water rats have a flat head and blunt nose, but common rats have tapered structured faces, also the toes of water rats are webbed because they live in water bodies. The ears of rats are prominent and visible while water rats have small ears and in species like the earless water rat, their ears can be completely absent. Water rats are chiefly carnivores and they prey on aquatic animals such as fish, frogs, reptiles, and even small birds and aquatic insects, while common rats eat grains, fruits, nuts, and vegetables along with small animals, insects, and garbage, etc.

Here at Kidadl, we have carefully created lots of interesting family-friendly animal facts for everyone to discover! Learn more about some other mammals including the porcupine and the water vole.

You can even occupy yourself at home by drawing one of our rat coloring pages.

Water Rat Facts

What Did They Prey On?

Aquatic insects and mammals

What Type of Animal were they?


Average Litter Size?


How Much Did They Weigh?

25-50 kg (55-88 lb)

What habitat Do they Live In?

freshwater lakes, lakes, rivers

Where Do They Live?

australian continent and nearby islands, new guinea

How Long Were They?

60-91 cm (24-36 in)

How Tall Were They?





Hydromes, Crossomys, Colomys



Scientific Name

Hydromys chrysogaster

What Do They Look Like?

Dark brown

Skin Type


What Are Their Main Threats?

water birds, humans, habitat loss

What is their Conservation Status?

Least Concern
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Written by Moumita Dutta

Bachelor of Arts specializing in Journalism and Mass Communication, Postgraduate Diploma in Sports Management

Moumita Dutta picture

Moumita DuttaBachelor of Arts specializing in Journalism and Mass Communication, Postgraduate Diploma in Sports Management

A content writer and editor with a passion for sports, Moumita has honed her skills in producing compelling match reports and stories about sporting heroes. She holds a degree in Journalism and Mass Communication from the Indian Institute of Social Welfare and Business Management, Calcutta University, alongside a postgraduate diploma in Sports Management.

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