Wild rats dig complex burrows in a matter of hours: what that says about the need to burrow
A rat that digs relentlessly through its bedding isn't just bored: it's expressing a behaviour deeply rooted in its wild relatives, capable of building burrow networks in a single night. Find our setup guidance in the rodent bedding and habitat section.
A study comparing wild and laboratory rats
Stryjek, Modlińska, and Pisula published a study comparing burrowing behaviour in wild rats and several laboratory rat strains in the journal PLOS ONE in 2012 (research on Google Scholar). The researchers measured that wild rats built burrows markedly faster and more complex than laboratory rats, consistently with at least two separate exits, compared with simpler, less finished structures in the domesticated strains.
What this means for bedding depth
Even far removed genetically from its wild cousin after generations of selective breeding, the pet rat retains part of this burrowing behaviour, which a thin layer of bedding never lets it fully express.
- Provide a bedding layer thick enough, several centimeters at minimum, in at least one dedicated digging zone of the cage.
- Offer a loose, safe substrate, such as shredded paper or a suitable bedding, rather than a thin layer laid down purely for looks.
- Don't worry about intense digging as long as it stays directed at the bedding rather than compulsive scratching at the cage walls.
This natural need adds to the other setup criteria covered in the fancy rat profile. Our page on fancy rat bedding and habitat details the recommended materials and volumes.
Frequently asked questions
Has a pet rat really kept this need to dig?
Yes, even far removed from the wild strain, it retains this behaviour, usually in a simpler form but no less present day to day.
How deep should the bedding be at minimum?
Several centimeters in one dedicated zone is usually enough to allow satisfying digging, without needing to cover the whole cage floor.
Does digging replace other forms of enrichment?
No, it adds to toys, tunnels, and social interaction rather than replacing them; each form of stimulation meets a different need. Find all our guides on the rodent hub.
This guide is part of Planète Pets’s Rodents universe. Our advice is general in nature: for any health concern, your veterinarian remains the only reference.