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How Long Can Rats Live Without a Food Source?

Rats, remarkable for their survival skills, thrive in various conditions but need food to survive. These opportunistic feeders eat almost anything, from plants to insects.

However, domestic rats rely on humans for food and face challenges if meals are skipped. Their survival without food depends on their health and the environment, and water significantly affects their chances.

What is the threshold before a rat's health begins to decline? Keep reading to explore how long rats can live without food.

Key Takeaways

  • Rats can survive up to two weeks without food in laboratory conditions if they have access to water.
  • In the wild, rats' survival time without food varies, usually lasting about a week, depending on factors such as fat reserves and water intake.
  • Physiological and behavioral adaptations, such as hoarding food and minimizing activity, help rats extend their survival during food shortages.
  • The survival ability of rats without food is also influenced by their age, health, and reproductive status, with younger and reproductive rats having a lower survival rate.
  • Managing rat infestations involves sealing entry points, maintaining cleanliness, and possibly consulting professional pest control services for complex infestations.

How Long Can Rats Live Without Eating?

You might wonder how rats, known for their hardiness, can survive periods without food. Here's a detailed look at their resilience in different environments and the impact on their lifespan:



In laboratory conditions

While no direct studies have been conducted on this, rats have been observed to survive without food for up to two weeks with a stable water source and a controlled climate.

In the Wild

Wild rats have been observed living without food for almost a week. However, this can differ significantly depending on various factors.

8 Key Factors Influencing Rat Survival Without Food

8 Key Factors Influencing Rat Survival Without Food

Several factors determine how long rats can survive without access to food, with survival duration varying among individuals.

1. Metabolic Rate

The metabolic rate of a rat plays a crucial role in its survival without food. Both rates dictate how quickly a rat will deplete its energy reserves without food.

Here’s a closer look at the different energy requirements they need in various states:

  • Basal Metabolic Rate (BMR): The minimum energy a rat requires to perform basic life-sustaining functions while at rest.
  • Active Metabolic Rate (AMR): This is the energy a rat expends during physical activities.

2. Fat Reserves

Fat reserves are an energy backup for rats during food shortage situations. Here's how different levels might impact their ability to sustain without food:

Fat Reserve Levels

Average Survival Time Without Food


Longer survival time


Shorter survival time

3. Water Intake

Water is vital for rat survival, even more immediately than food. These signs can lead to a quicker decline in their health when food is scarce:

  1. Loss of skin elasticity: A sign of dehydration.

  2. Concentrated urine: Indicates reduced water intake.

  3. Lethargy: A typical response to dehydration.

4. Behavioral Adaptations

When human food is unavailable, certain behaviors extend the survival of species, like roof rats or black rats. These adaptations prove to be beneficial during periods without food:

Behavioral Adaptations



Collecting and storing food for lean times enhances survival prospects.

Reduced Activity

Minimizing energy expenditure helps conserve stored fats and energy.

5. Physiological Adaptations

Rats endure food scarcity through several physiological changes. Through these adaptations, rats can elongate their survival window.

Here’s how each starvation phase triggers distinct physiological responses in rats, shaping their survival strategies.

  • First 24 Hours: Rats experience an immediate impact on their metabolism, transitioning from using stored glycogen to metabolizing fat for energy.
  • Day 2-3: The body increasingly relies on fat reserves for energy.
  • Day 4-7: After the fat reserves start depleting, the body shifts towards breaking down proteins, primarily from muscle tissue.
  • Beyond 7 Days: The body struggles to maintain basic functions; survival depends on external intervention.

6. Reproductive Status

A rat's reproductive status influences its energy requirements and survival without food. Here’s how reproductive activities affect a rat's ability to withstand periods without food:

Reproductive Status

Survival Rate


Higher survival rate

Pregnant Female Rats

Lower survival rate due to increased energy demands

Lactating Female Rats

Significantly reduced survival rate

7. Health and Age

Physical well-being and age are critical in assessing a rat’s resilience without food. Here’s how a rat's ability to survive without food varies significantly with age:

  1. Young Rats: May have less fat reserves; dependent on their mother's milk.

  2. Adult Rats: Generally have greater resilience and fat reserves.

  3. Elderly Rats: Often have a diminished ability to survive without food due to deteriorating health.

8. Environmental Conditions

The environment heavily influences the capacity of many rat species, like brown rats, to endure without food. Here’s how different conditions can impact rat lifespan:

Environmental Conditions



Hot or cold extremes affect metabolic rate and survival.


Availability and quality provide protection and conserve energy.

How to Manage and Prevent Rat Infestations

Managing and preventing infestations from species like Norway rats is crucial because rats can cause extensive problems in homes and carry diseases.

Here’s how you can tackle and get rid of your rat problem effectively:

  1. Identify Entry Points: Sewer rats can enter gaps in the attics or basements as small as a quarter.

  2. Store Food Properly: Rats invade homes looking for human or pet food.

  3. Maintain Cleanliness: A tidy home is less attractive to rats looking for nest habitats.

  4. Utilize Snap Traps: Snap traps can be humanely managed for rat control.

  5. Professional Exterminator: An exterminator has the experience and tools for safe rodent control and can offer advice to prevent future infestations.

  6. Monitor for Further Activity: Spotting signs of rats, such as droppings, gnaw marks, or hearing noises in the walls, helps in early detection.

When to Call a Professional Rat Control

As homeowners, you often try to tackle rat infestations on your own. But there comes a point when calling in professional rat control services is necessary.

So, if you find rat-infested areas hard to reach or notice rats have chewed through electrical wires, posing a fire hazard, immediately call a professional pest control company (like us at Native Pest Management).

As professional control services, we offer expertise, safety, and prevention for your rat problems.