Norway Rat

Rattus norvegicus

Norway rats, the species most commonly used as pets, originated in China but quickly spread throughout the world. They can now be found on every continent, and have found success living alongside humans. Rats are very intelligent and curious animals. Although they are often thought of as a pest species they can be a very nice companion. Rats can be 14 to 18 inches long including their tail. They often only live two to three years in captivity, and do best in a pair. Rats are nocturnal so they are most active at night.  Rats have a diverse diet, in the wild they will eat fish, bugs, and small animals as well as plants. When found alongside humans rats are effective scavengers and eat discarded food.

Did You Know?

Rats are very intelligent and curious animals.


Does the harvest for wildlife trade or captive breeding of this species harm wild populations?

Little Cause for Concern

Rats are found all over the world and humans often try to exterminate them. They are not sourced from the wild for pets and can be purchased from breeders or pet stores, and even adopted from shelters.

EcoHealthy Recommendation:

When purchasing a pet rat only acquire from a reputable, pet store, hobby breeder or shelter. This will ensure the health of the animal and minimize health risk to your family.

Invasion Threat

Does the release or escape of this species into the wild harm the environment and/or economy?

Some Cause for Concern

Norway rats are listed in Florida as an invasive species by the Center for Invasive Species and Ecosystem Health. Rats are common almost anywhere and are considered a pest species in many places. Although other means contribute more to the invasion of rats, the pet trade still presents a risk.

EcoHealthy Recommendation:

Before obtaining any non-traditional pet, check that it is legal to own one in your state of residence and check for permitting requirements. Always keep your pet inside a safe and secure enclosure. Never release a pet into the wild.

Ease of Care

Does harvest, captive breeding, transport, or being kept as a pet harm individual animals?

Little Cause for Concern

Ease of care of many non-traditional pets depends on the individual owner’s years of experience and knowledge caring for a particular species. For the purposes of this website, we have geared information toward the benefit of the beginner.

Rats are intelligent and social creatures and do best in a pair or small group. They need daily interaction with their owner and time out of the cage to explore and exercise. Since they are nocturnal, they may not be the best choice for younger children who will want to play during the day. Their diet should consist of rat chow and daily fruits or veggies. They can occasionally be given healthy human food as a treat, such as chicken or egg. Like most rodents they will need toys or sticks to chew to prevent their teeth from getting too long, since they grow constantly. Due to their intelligence rats need more time for play and enrichment than other rodents and this requires more of a time commitment.

EcoHealthy Recommendation:

Before acquiring a rat, be sure to research its specific care requirements. Make sure to buy from a reputable source to increase your chance of receiving a healthy animal.

Health Threat

Does this animal pose a health risk to native wildlife, humans, livestock and agriculture?

Some Cause for Concern

Rats can carry Salmonella, and Lymphocytic choriomeningitis, a virus that can cause meningitis and encephalitis. Young children and the immunocompromised are at an increased risk of contracting these diseases from a pet, but if you practice proper hygiene these risks are minimal.

Rat bite fever is a concern for people who handle rats regularly. It is caused by the bacteria Streptobacillus moniliformis and can cause serious health problems in humans. This illness can be transmitted by bites, scratches and even just handling an infected animal. To help decrease risk make sure you bring your pet in for regular vet checkups, get it from a reputable source and wash your hands after handling your rat.

EcoHealthy Recommendation:

Make sure you purchase or adopt your rat from a reputable source, to increase your chance of receiving a healthy animal.

EcoHealth Alliance works at the intersection of ecosystem, animal and human health through local conservation programs and develops global health solutions to emerging diseases.
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