Gerbil and Mongolian Gerbil Welfare in Captivity

Gerbils are social, burrowing rodents with specific welfare needs often unmet in pet keeping. Understanding their natural behaviour helps owners provide appropriate care.

Key Facts

Mongolian gerbils are social animals that live in family groups in the wild and should always be kept in pairs or groups
They are crepuscular, most active at dawn and dusk
Gerbils dig extensive tunnel systems in the wild and require deep substrate to burrow in captivity
They are desert-adapted animals from Mongolia that require low humidity environments
Gerbils introduced to a new companion as adults can fight fatally without careful introduction protocols
Declans (gerbil group breakdowns) when a pair bond breaks can result in fatal fighting between previously bonded gerbils

Welfare Considerations

Gerbils kept alone develop repetitive stereotypic behaviour (corner digging, repetitive bouncing) indicating chronic stress from social deprivation. Standard gerbil tanks without deep burrowing substrate prevent the tunnelling that is central to gerbil natural behaviour and psychological wellbeing. The gerbil declan phenomenon — where a previously bonded pair suddenly fights, often fatally — is poorly understood by most owners and represents an acute welfare emergency. High humidity in typical UK homes can cause wet-tail in gerbils kept without appropriate substrate. Gerbil epilepsy, common in pet gerbils, causes distress during seizures and requires careful management including avoiding triggering stimuli.

What You Can Do

Keep gerbils in pairs or trios of same-sex animals from the same litter where possible
Provide at least 30 cm of deep burrowing substrate (paper-based or organic soil mixtures)
Learn to recognise early signs of declan breakdown including chasing and fighting to separate pairs before fatal injury occurs
Avoid handling gerbils in ways that trigger their epilepsy — sudden loud noises and rapid movements are common triggers