Rats Pest Control and Treatment

Rats Pest Control

Rats are larger rodents than mice and are among the most destructive household pests in Australia. The two species most often found in homes are the brown rat (Norway rat) and the black rat (roof rat). Brown rats are heavyset and robust, while black rats are slimmer, with pointed noses and larger ears.

Rats breed prolifically — females can reproduce from as early as three months old, producing 4–5 litters a year with up to 10 pups per litter. With lifespans of around 12–18 months indoors, populations can explode quickly if left unchecked. Beyond being a nuisance, rats are a serious health hazard as they spread diseases and contaminate food. They are also known to gnaw on electrical wiring, which makes them a fire risk in homes and businesses

What Do Rats Look Like?

Rats are significantly larger than mice, with bodies ranging from 200–500 mm in length depending on the species. Brown rats are stockier, with a blunt snout, small ears, and shaggy brown-grey fur. Black rats are sleeker, with a pointed snout, large ears, and smoother dark fur. Their tails are long and scaly,  often as long as, or longer than, their body length.

Both species have continuously growing incisors, which is why they constantly gnaw on wood, plastic, wires, and even soft concrete to keep their teeth in check. Their droppings are much larger than mouse droppings, measuring 12–18 mm long, and are often one of the first signs of an infestation.

Where Do Rats Live?

Rats are highly adaptable and can make nests in a wide range of environments. Indoors, they often live in roof voids, wall cavities, subfloors, and storage areas, using shredded materials, insulation, or cardboard to build their nests. Outdoors, they burrow into banks, compost heaps, or under sheds, and black rats are excellent climbers, often nesting in trees, roof spaces, and ceilings.

They prefer dark, secluded spots close to food and water. Because they need more water than mice, they are often found near drains, sewers, or leaking pipes. Once inside, rats quickly contaminate food supplies, damage property, and spread filth wherever they travel.

Common Types of Rats in Australia

Australia has several species of rats, including natives like the bush rat and water rat, but these rarely cause problems in homes. The two species responsible for most infestations and damage are the Norway rat and the roof rat. They are both introduced pests that spread disease, contaminate food, and damage property.

Norway Rat (Rattus norvegicus) 

How they look 

Also known as the brown rat, the Norway rat is the largest and most common rat species in Australia. They have a heavy, stocky build, weighing around 450 grams, with coarse reddish-brown to grey fur, a blunt nose, and small ears covered with fine hairs. Their droppings are large and blunt-ended, measuring about 18 mm long.

Where they live 

Norway rats are extremely adaptable and will infest homes, factories, warehouses, farms, and garbage dumps. Indoors, they often nest in roof voids, wall cavities, and subfloors. Outdoors, they burrow into banks, compost heaps, and under sheds. Unlike other species, they require regular access to water and prefer larger meals rather than frequent foraging.

Why they are a problem 

These rats are prolific breeders, with females capable of producing 5–6 litters per year. They contaminate food stores with droppings and urine, gnaw through wood and packaging, and can chew on electrical wiring — often causing short circuits and fire hazards. Their presence poses serious health risks as they spread disease through direct contact or contaminated surfaces.

Roof Rat (Rattus rattus) 

How they look 

Commonly called the black rat or ship rat, the roof rat has a slender body with dark brown to black fur, often lighter or whitish underneath. They have a pointed snout, large prominent ears, and a tail that is as long as, or longer than, their body. Their droppings are smaller than those of Norway rats, around 12 mm long, with pointed ends.

Where they live 

Roof rats are skilled climbers and prefer elevated areas. They nest in roof voids, wall cavities, and trees, and are often found in coastal areas, ships, and seaports. Unlike Norway rats, they rarely burrow and feel safest in higher locations. They feed mainly on nuts, grains, fruits, and fungi, and prefer food with high moisture content.

Why they are a problem 

Roof rats reproduce quickly, reaching sexual maturity within 3–4 months and producing 4–5 litters a year, with up to 8 pups per litter. They damage property by gnawing and can transport food away from its source, contaminating multiple areas. Their presence indoors leads to food contamination, property damage, and increased risk of disease transmission.

How to Identify Rats Infestations

Droppings and Tracks

Rats leave behind droppings that are much larger than those of mice, typically 12–18 mm in length with blunt ends. These are often found in clusters near food stores, along walls, or close to their nests. Their regular pathways may also show greasy rub marks or footprints in dusty areas.

Sounds in Walls and Roofs 

At night, rats become most active. They can be heard scratching, gnawing, or scurrying in ceilings, under floors, and inside wall cavities. In larger infestations, you may even hear squeaks, chattering, or grinding noises from their teeth.

Odour and Contamination 

One of the most unpleasant signs of a rat infestation is the strong ammonia-like smell from their urine. This odour tends to linger around nesting areas and grows more intense as the population increases. Rats also contaminate food with urine, droppings, and hair, making it unsafe to eat.

Property Damage

Rats constantly gnaw to wear down their teeth, which never stop growing. This results in chewed packaging, furniture, pipes, and electrical wiring. Damage to cables is especially dangerous, as it can spark fires or short circuits in homes and businesses.

Nesting Behaviour 

Rats build nests in dark, secluded spaces such as roof voids, wall cavities, basements, and under sheds. Indoors, they use shredded materials like cardboard, insulation, and fabric to create warm, hidden shelters. Outdoors, Norway rats often burrow into the soil, while roof rats prefer nesting above ground in attics or trees.

Visible Activity

Spotting a live rat is a major red flag. Rats are cautious and tend to avoid human activity, so daytime sightings usually indicate a large, well-established colony. In heavy infestations, multiple rats may be seen moving around, along with widespread droppings, gnaw marks, and foul odours.

Signs of Heavy Infestation

In severe infestations, the signs become impossible to ignore. Multiple rats may be seen during the day, droppings and urine trails will be widespread, and strong odours will linger throughout the home.

Structural damage such as gnawed wires, chewed food packaging, and shredded nesting materials may be found across several rooms. At this stage, the risks of disease, fire hazards, and property damage make professional pest control essential.

How to Prevent Rats Infestations

Rats are larger, stronger, and more destructive than mice. Once inside, they breed quickly, spread disease, and can cause serious property damage by gnawing through walls, wires, and even pipes. Prevention is always easier and safer than dealing with a full-blown infestation, so taking proactive steps to make your home less attractive to rats is essential.

Cut Off Their Food Supply 

Rats are not picky eaters,  they will chew through cardboard, plastic, or even soap to reach food. Store pantry goods like grains, cereals, and pet food in heavy-duty airtight containers. Outdoor rubbish bins should be sturdy with tight-fitting lids. Collect fallen fruit, secure compost heaps, and clean up leftovers immediately to avoid attracting hungry rodents.

Remove Easy Access to Water

Unlike mice, rats need a regular water source. Check for leaking taps, pipes, or garden hoses and repair them quickly. Avoid leaving pet water bowls or birdbaths out overnight. Even small sources of standing water can keep rats coming back.

Deny Shelter and Nesting Spots 

Rats seek out warm, hidden areas for nesting. Keep storage areas like garages, attics, and sheds organised and clutter-free. Store firewood off the ground and away from your home. Outdoors, trim overgrown shrubs, cut back long grass, and remove piles of leaves or garden debris that could provide cover.

Seal Off Entry Routes 

Rats can gnaw through wood, plastic, and even soft concrete, so sealing gaps is critical. Inspect your home for holes in walls, around plumbing, and along the roofline. Use durable materials such as wire mesh, steel wool, or metal flashing to block these openings. Don’t forget chimneys, vents, and drains — roof rats in particular are agile climbers.

Use Repellents Wisely 

Strong smells like peppermint, eucalyptus, or ammonia may discourage rats from lingering. Cotton balls soaked in these scents can be placed in cupboards, under sinks, or near entry points. While these won’t solve a heavy infestation, they can act as an added deterrent alongside other preventive steps.

Regularly Maintain Your Home

Rats are most active in cooler months when they seek warmth indoors. Inspect your property seasonally, especially before winter, to ensure no food, water, or shelter is available to them. A tidy, well-sealed home is the strongest long-term defence against these pests.

Beware of Indoor Plants and Vegetation

Fruit-bearing indoor plants and poorly managed garden vegetation can attract rats. Indoor pots provide warmth, water, and shelter, making them ideal nesting sites. Outdoors, tall weeds, dense bushes, and tree branches that touch the roofline act as pathways for roof rats to reach attics and roof voids. Keep vegetation trimmed and avoid bringing food-producing plants inside.

How to Get Rid of Rat Infestations

Rats are larger, stronger, and far more destructive than mice. They contaminate food, chew through wiring, spread over 35 different diseases, and reproduce quickly with females producing several litters a year. Eradicating them isn’t all that easy. For example; did you know a rat can tread water for up to 3 days? Or that they’re known to transmit several potentially fatal diseases to humans? What about the fact that female rats can mate as many as 500 times with various males during a 6-hour period of receptivity?

Because of their intelligence and wariness of new objects, rats can also be more difficult to trap and eliminate than mice. Complete control usually requires a combination of at-home measures and professional pest management.

At-Home Actions to Get Rid Of Rats

Use Baits Safely

Poison baits remain one of the most effective ways to kill rats. Some local councils even supply bait blocks free to residents. Always place baits inside tamper-resistant stations so that pets and children cannot access them. Check bait stations daily during a large infestation,  a single rat can consume an entire box of bait in one night. Replace any eaten baits promptly to maintain effectiveness.

Use Traps Safely

Traditional snap traps are still among the most reliable for home use, though enclosed plastic capture boxes are also available. Experiment with different baits such as bacon, sausage, apple, pumpkin seeds, nuts, or fish to find what attracts rats in your area. Place traps along walls, near droppings, or in roof voids where activity is highest.

Reduce Food and Water Access

Rats are opportunistic eaters and will chew through thin packaging to reach food. Store pantry staples and pet feed in heavy-duty airtight containers. Collect fallen fruit from gardens, secure outdoor bins with tight-fitting lids, and avoid leaving pet food or water bowls out overnight. Fix leaking taps and pipes promptly, as rats need a steady water source to survive.

Deny Shelter

Rats seek warm, hidden spaces for nesting, especially during winter when they move indoors. Keep storage areas tidy and clutter-free, and store firewood off the ground and away from walls. Outdoors, trim overhanging tree branches that can act as “bridges” into your roof, and clear away debris, weeds, and leaf piles where rats can hide or burrow.

Professional Rat Treatments

While traps and baits can reduce numbers, large infestations are rarely eradicated without professional help. Licensed pest controllers use targeted treatments and exclusion methods to ensure long-term results.

Baiting Programs

Technicians place tamper-resistant bait stations around your property, using formulations designed to attract rats but minimise risk to pets and children.

Trapping and Exclusion

In sensitive areas, trapping is often used alongside exclusion work. Pest controllers can identify and seal entry points such as roof gaps, wall voids, or damaged vents to prevent reinfestation.

Follow-Up Visits

Because rat populations can rebound quickly, follow-up inspections and treatments are usually scheduled to confirm the infestation has been completely eradicated.

Call a Pest Control Professional

Rats aren’t just a nuisance, they’re a public health hazard. Diseases can spread directly through bites, droppings, and urine, or indirectly through fleas, ticks, and mites that feed on infected rats. The risk is especially high in winter, when rats move into homes, sheds, and even cars to escape the cold.

A licensed pest control company can confirm the extent of the infestation, apply safe and effective treatments, and provide advice on long-term prevention. Eco-friendly and non-toxic options are also available if you want to minimise chemical use.

Need help now? Book a professional rat inspection on 1300 766 614. Our experts will assess your property, explain your options, and create a tailored plan to eliminate rats and stop them from coming back.

Frequently Asked Questions (FAQ)

What should I do if I have rats on my property?

If you notice signs of rats, it’s important to act quickly before the infestation grows. Talk to your neighbours, as rats often travel between properties and may be breeding nearby. You should also report rat activity to your local council’s environmental health officer, who may provide advice or even free baiting options. If the problem persists, contact a licensed pest control company for safe and effective treatment.

What do rats eat? 

Rats are opportunistic feeders and will eat almost anything, including grains, fruit, vegetables, nuts, pet food, and household scraps. They’ve also been known to chew on soap, leather, and even other rodents if food is scarce. Their adaptability is one of the reasons they thrive in human environments.

How long do rats live? 

In the wild, most rats live for about 9–12 months due to predators and environmental risks. Indoors, however, with a steady food supply and protection from danger, rats can survive up to 2–3 years. During that time, they reproduce quickly, which makes infestations hard to control without intervention.

Can rats climb walls? 

Yes. Roof rats (black rats) are excellent climbers and can easily scale walls, trees, and even utility lines to access attics and roof voids. Norway rats are poorer climbers but skilled burrowers, often nesting under buildings or in gardens.

How big can rats get? 

Norway rats are the largest rat species in Australia, reaching 40 cm in total length (including the tail) and weighing up to 500 grams. Roof rats are slimmer and lighter, but their long tails make them appear just as large.

Are bush rats dangerous?

Bush rats are native to Australia, and, unlike introduced Norway and roof rats, they are not typically pests in homes. They are shy, mostly nocturnal, and prefer forested or bushland habitats. While they don’t usually spread disease to humans, they may still cause damage if they venture indoors or raid gardens.