A captive enclosure cannot reproduce every feature of a degu’s natural environment. Appropriate food and conscientious care remain essential, but owners should also observe behaviour and the opportunities available to the animals. Repeated bar chewing, fur pulling or apparently excessive wheel use may give cause for concern; each needs assessment rather than an automatic diagnosis of stress.
Behavioural problems and stereotypies
“Behavioural problem” is a broad practical term. It may concern aggression, feeding, social interactions, repetitive activity or self-injury. A behaviour that inconveniences an owner is not necessarily abnormal for the species, and several different problems can occur in the same animal.
Different descriptions
- Abnormal behaviour is activity that differs in important ways from an appropriate species-typical pattern. Natural behaviour and the individual’s circumstances provide context, rather than a simple wild-versus-captive checklist.
- Abnormal repetitive behaviour is a broader description used when activity is repeatedly expressed in an apparently inappropriate way. Its causes may be uncertain.
- Compulsive behaviour requires professional assessment. Human diagnostic classifications of obsessive-compulsive disorder cannot simply be applied to a degu from a short observation.
- Behaviour associated with disease may reflect pain or another physical problem. For example, fur pulling can occur with discomfort, including dental disease, but the cause must be investigated rather than assumed.
What is a stereotypy?
A traditional description is a repetitive, relatively unchanging pattern with no obvious immediate purpose. Researchers also discuss the mechanisms that produce it, including frustration, restricted opportunities and altered behavioural control. Terminology varies: the distinction is not a simple universal rule that a known biological cause makes a stereotypy and an unknown cause excludes it.
Such patterns may persist for years and sometimes remain after conditions improve. They can be a warning about past or present welfare problems, but their presence does not identify a single cause, and their absence does not prove good welfare.
In practical degu care, this article considers repeated bar chewing, persistent fur pulling and other unusual repetitive activities together, without claiming that every example has the same mechanism. Repeated pacing or running may reflect thwarted exploration or foraging in some circumstances, but an observer cannot infer that motive from movement alone.
Possible influences
Health, previous experience, development, housing, social conditions and inherited susceptibility may all matter. A bank-vole study found evidence consistent with a genetic contribution to stereotypies in that species; it does not prove genetic transmission or imitation from parents in degus. Prenatal stress and early separation are possible developmental influences to investigate, not a diagnosis for every affected litter.
Life in captivity
Species differ in how their natural behaviour fits a captive setting. The original comparison between pandas and giraffes should not be taken as a validated ranking of their ability to tolerate captivity. Degus explore, dig, forage and maintain social relationships; appropriate variety and choices are useful, but repeatedly replacing their familiar territory is not required.
Confinement may frustrate an animal’s attempts to reach another area or companion. Early separation and the circumstances surrounding the opening of a cage may also influence behaviour. These are possibilities to assess, rather than evidence that every degu chewing bars simply wants the door opened.
Anticipation and routines
Activity may increase around familiar feeding cues, including sounds, gestures and the owner’s arrival. Anticipation can contribute to frustration when opportunities are limited, but predictability is not inherently harmful. A reliable routine and a regular light–dark cycle remain important. Vary activities and food presentation without making essential care erratic.
Patterns owners may observe
The examples below combine published veterinary information with the author’s experience. Their frequency and causes are not established by a population survey. It is inaccurate to claim that no behavioural literature exists for degus; the detailed evidence for each particular repetitive pattern is nevertheless limited.
Bar chewing
Repeatedly biting and releasing cage bars, sometimes with sideways head movements or contact with two bars at once, can be noisy and may damage the incisors. It can occur on horizontal or vertical bars. Possible influences include confinement, frustration and stress, but brief biting is not automatically a stereotypy. The bar-chewing guide explains how to investigate it.
Fur pulling and excessive grooming of companions
Self-directed fur pulling may leave localised bare areas, including the forelegs and sometimes the thighs. When another animal removes the fur, the head, areas around the eyes or muzzle, and the back may be affected. These locations are observations, not proof of a behavioural diagnosis: parasites, skin disease and pain must also be considered. Read about fur loss and seek veterinary assessment.
Wheel use
Some owners report apparently excessive running or an animal using the wheel while frightened. There is no established universal time threshold that separates normal degu wheel use from a stereotypy. Assess whether the animal can rest, eat and interact normally, whether the wheel is safe, and whether heat, distress or injury is involved.
Repeated digging
Repetitive digging in the same location is well studied in some other rodents, including gerbils. Similar patterns are sometimes reported in degus, but digging itself is a normal activity. Its form, context, duration and consequences require attention.
Destructive activity
Chewing and dismantling objects are normal parts of degu behaviour. Completely destroying an accessory does not, by itself, establish a stereotypy or territorial disorder. Offer safe gnawing materials and investigate if activity becomes inflexible, injurious or interferes with other needs.
Improving care
Record when the behaviour occurs, its duration and what happens around it. A vet should investigate possible pain or disease; a qualified clinical behaviour professional may help with persistent problems. Causes are not always easy to identify, and improvement cannot be promised from a single change.
Provide appropriate usable space
Degus are active, partly burrowing rodents. Although they climb well, they also need room to run and move along broad, secure surfaces. A tall cage that permits only climbing is not equivalent to ample horizontal movement. The original article suggests a cage at least 1 m long and refers to the CARA assessment of at least 18,000 cm² of usable floor-and-platform area for two animals. This is a community assessment framework, not a substitute for evaluating the complete enclosure.
Suitable adaptations of large aviaries or ferret-style cages may provide useful space, but check bar spacing, materials and safety. Read the housing guide and CARA explanation before choosing.
Offer several refuges
A threatened wild degu may freeze and then retreat to shelter. Provide accessible hiding places in different parts of the enclosure so that animals can withdraw without becoming trapped or being excluded by a companion.
Manage anticipation carefully
Do not attempt to cure repetitive behaviour simply by changing feeding and bedtime every day. Keep food, water, rest and lighting reliable. Use gradual changes to enrich how food is found, and avoid repeatedly rewarding a bar-chewing sequence with immediate attention or release.
Provide alternative activities
Where lack of opportunity is a concern, additional suitable wheels or activities may help distribute access. The original suggestion of one wheel per degu is an option to evaluate, not a guaranteed treatment for fur pulling. Maintain enough safe space around equipment and monitor the animals’ response.
Use suitable enrichment
Scatter measured dry food in clean areas or offer it in simple puzzles, such as plain paper folded or crumpled around a small portion. A bowl remains optional; removing every bowl is not automatically the best treatment. Secure, safe temporary objects—earthenware pots, suitable stones or untreated branches—can add variety. Whole suitable plants, such as a dandelion, or appropriate hazel branches may provide longer investigations than small fragments. Assess plant identity, cleanliness, stability and chewing hazards.
Introduce enrichment gradually, retain familiar shelter and scent, and observe its effect. The goal is a better daily life and wider behavioural choices, not simply suppressing a visible symptom.
Sources
Mason, G., & Rushen, J. (Eds.) (2006). Stereotypic Animal Behaviour: Fundamentals and Applications to Welfare. Second edition. CABI. https://doi.org/10.1079/9780851990040.0000
Mills, D., & Luescher, A. (2006). Veterinary and pharmacological approaches to abnormal repetitive behaviour. In Stereotypic Animal Behaviour: Fundamentals and Applications to Welfare, pp. 286–324. CABI. https://doi.org/10.1079/9780851990040.0286
Schoenecker, B., & Heller, K. E. (2000). Indication of a genetic basis of stereotypies in laboratory-bred bank voles (Clethrionomys glareolus). Applied Animal Behaviour Science, 68(4), 339–347. https://doi.org/10.1016/S0168-1591(00)00114-3
Jekl, V., Hauptman, K., & Knotek, Z. (2011). Diseases in pet degus: a retrospective study in 300 animals. Journal of Small Animal Practice, 52(2), 107–112. https://doi.org/10.1111/j.1748-5827.2010.01028.x
RSPCA (n.d.). Caring for pet degus. Behaviour and welfare guidance. https://www.rspca.org.uk/en/adviceandwelfare/pets/rodents/degus/behaviour