Rat Life Cycle: Lifespan and Habitat

Rat life cycle
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Rats can be found all over the world. However, they originate from Asia and Australia. Rats are generally known as nasty disease spreading animals, associated with causing plague epidemics and bringing on loads of troubles to homeowners everywhere.

There are a number of different species known to humankind. The most common rat species in Australia are perhaps the brown and the black rat. But no matter the species, these pests are known to cause plenty of property damages and health hazards.

What makes it difficult to deal with them is that rats multiply rapidly. Due to that, wild rats are considered a huge enemy of homeowners. From gnawed wires to burrows, if you notice their presence in your property, it is better to act quickly.

How long do wild rats live?

The life expectancy of wild rats is around 2 to a maximum of 3 years with female rats usually outliving male rats. However, due to predators and interspecies conflicts, most rats' lifespan is even shorter.

The biggest enemies of rats include cats and dogs, some huge birds and wild animals. Adding to that other determining factors such as environmental conditions and the genetics of the rodent, many rats die even after their first year.

The lifespan of the two most common rat species in Australia, the brown rat and the black rat, does not differ much.

However, black rats tend to be smaller in size than their brownish cousins. Thus, if there is a fight for dominance, black rats usually find themselves on the losing side and can easily be killed by the larger species. Surprisingly, this is not the case in Australia, where the population of black rats is much bigger than the one of brown rats.

Considering the rats’ short lifespan, if you think that a year of having a rat problem is not so much and you can wait for it to pass through, you can’t be more wrong.

Firstly, rats can cause a decent amount of trouble to the residents and the house. Secondly, rats leave behind large offspring. Let’s say you are lucky enough that the initial rats that have found shelter in your home die after a year. Then you will still have to deal with their children and the children of their children. It is a closed and troublesome cycle. That is why when you notice the first signs of rats living under your roof, you need to take quick action and contact a professional pest control company.

Where do rats live?

Wild rats spread easily. As pests, they take over places that provide shelter and secure them easy access to food and water, while causing havoc on their way. Rats can be found inside walls, garages, roofs, cabinets, basements, under sinks or near waste disposal areas. They mostly prefer warmer climates, however, the brown rat is found in places with a temperate climate.

Brown rats’ distribution is mainly throughout the southeastern Australian coast. They nest in urban areas, close to humans, however, they still prefer to hide in the underground or build their burrow systems. Preferred by the brown rat homes are sewers and bushes.

Black rats are distributed throughout most of the coastline of Australia. They prefer to inhabit ports and seaside towns around the country but can also be seen in rural and remote areas. The black rats can take shelter inside walls and burrows of farms but because they are also very good climbers, their habitat can include roofs and trees.

The behaviour of a rat

Rats are social animals. Most of them live in nests consisting of a leading male, several females and their pups. Male rats are very aggressive and often fight for females and social dominance. They can swim up sewer pipes and travel great distances in search of food and shelter.

Because of that, they can be very cautious of unknown objects standing in their way. Thus, traps set by humans can often prove pointless in catching a rat. When inhabiting a home, wild rats are known to cause various property damages and problems to homeowners such as contaminations, creating burrows, and chewing wires.

In addition, a female rat guarding a nest can be very aggressive and dangerous. If they felt threatened, they might attack humans. In the wild, rats can prey on small wildlife animals such as invertebrates, as well as birds, reptiles and their eggs.

Wild rats are nocturnal creatures, however, they can also be seen throughout the day. Their eyesight is relatively poor. But despite that, they have a very well-developed hearing and a strong sense of smell that is better than many other animals.

Rats can register chemicals coming from a change in the atmosphere or emotions using their noses. However, they also have a second smell organ (VNO) that they use to sense the pheromones of other rats from the same species.

Rats’ breeding cycle

Wild rats are a serious pest problem and can be very difficult to get rid of once they have found shelter under your roof. One of the reasons for this is because they multiply impressively fast.

Rats are generally weaned around 21-28 days after their birth. Brown and black wild rats reach their sexual maturity at relatively the same age. Male rats reach it in 6 to 10 weeks while females are ready to mate and reproduce in 8-12 weeks.

The gestation period of rats can last just a few weeks (approximately 20-22 days). Having in mind that the gestation period is relatively short, a female rat can produce 5 to 6 litters per year, each commonly consisting of about 5-10 baby rats (known as pups).

However, sometimes a litter can consist of up to 12 pups! Therefore, if you have to do the math, just two rats can quickly become around 1,250 rats in a just one year period.

Are rats omnivores?

Wild rats have the fame of being omnivores and that is, in fact, true. This means they can eat a wide range of plant- and meat-based foods. Yet, if rats are able to get their hands on meat they would prefer it. For easier access to food, rats use humans. They go through unprotected food leftovers and scavenge garbage. Rats are also blamed for the extinction of many wildlife species, such as small mammals, birds, reptiles and plants.

Learn what specific kind of food attracts rodents most here.


  • Wild rats can be dangerous as they sometimes attack people, especially when guarding their pups.
  • They also pose a danger to your property’s condition and your health by transmitting diseases.
  • Handling a rat infestation can be extremely difficult as they are hard to catch and can reproduce quickly.
  • Even if you poison the rodent, it won’t make it leave your property to die somewhere else. Instead, it will hide in a burrow within the house and die there, leaving you with unpleasant and smelly consequences.
  • If you find yourself with rats for housemates, it is better to contact professionals immediately and let them deal with the problem.

Do you think you have rats at home? Act quickly, contact us and let us solve this infestation for you!

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