How long does a rat live? - briefly
Pet rats usually live 2–3 years, whereas wild rats average about one year. Lifespan varies with species, care, and environment.
How long does a rat live? - in detail
Rats typically reach maturity within two to three months and can survive for a relatively brief period compared to larger mammals. In controlled environments, such as laboratory colonies or domestic settings, the average lifespan ranges from 2.5 to 3.5 years. Wild individuals usually live shorter lives, often less than one year, due to predation, disease, and variable food availability.
Key determinants of longevity include:
- Species: The common brown rat (Rattus norvegicus) generally outlives the black rat (Rattus rattus) by several months.
- Genetics: Selective breeding for health traits can extend life expectancy by up to a year.
- Diet: Balanced nutrition, low in excess fats and sugars, reduces the incidence of metabolic disorders.
- Housing: Enclosures that prevent injuries, provide enrichment, and maintain proper temperature and humidity support longer survival.
- Health care: Routine veterinary examinations, vaccination against common pathogens, and prompt treatment of respiratory or gastrointestinal infections improve outcomes.
Common causes of premature death are respiratory infections, neoplastic diseases, and traumatic injuries. Laboratory strains often exhibit longer lifespans because of standardized housing, pathogen‑free environments, and regular health monitoring. Conversely, feral populations face constant environmental stressors that truncate their lifespan.
Maximum recorded ages approach five years for exceptionally well‑cared pet rats, but such cases are outliers. The realistic expectation for most owners or researchers lies within the 2–4 year window, with the majority of individuals dying between 2.5 and 3 years under optimal conditions.