Ferret

About the species

The ferret (Mustela putorius furo, also written Mustela furo) is the domesticated form of the European polecat and belongs to the weasel family, Mustelidae – it is a carnivore, not a rodent. People have kept ferrets for more than 2,000 years, first mainly for hunting rabbits and today mostly as pets. Females are typically 33–35.5 cm long and males 38–40.6 cm, with a further 7.6–10 cm of tail. An entire male can weigh up to 2 kg and a female up to 1.2 kg. With good care, a ferret usually lives 6 to 10 years.

A carnivore, not a rodent

A ferret is a carnivore and needs food that is high in protein and fat and low in carbohydrate and fibre. The Merck Veterinary Manual gives 35–40% protein, under 25% carbohydrate and under 2.5% fibre. The simplest base is a food made specifically for ferrets; according to the UK veterinary charity PDSA, dog or cat food is not suitable. The Merck Veterinary Manual also allows good-quality kitten food, so discuss this with your vet. Because ferrets eat little and often, kibble and fresh water should be available throughout the day. According to the RSPCA, bread, cereals and other starchy or high-fibre foods have no place in a ferret's diet.

How much space and time a ferret needs

A ferret needs far more room than its size suggests: PDSA recommends a minimum floor space of 10 m² for a pair, plus several hours of play outside the enclosure every day. Ferrets can sleep 18 to 20 hours a day, yet when awake they are relentless explorers. They are naturally most active at dawn and dusk, but many adapt to their owner's daily routine. Any room a ferret roams freely has to be ferret-proofed: gaps behind furniture closed, cables out of reach and no soft rubber or foam items left lying around. VCA notes that swallowing foreign objects is a common problem in ferrets, especially those under a year old.

The company of other ferrets

Most ferrets enjoy living in a pair or a small group. PDSA advises against keeping one on its own, while the RSPCA accepts that a single ferret can do well only with daily human companionship. For a group, the RSPCA suggests a maximum of four, ideally littermates and all neutered, since entire males may be more aggressive. As a predator, a ferret should never share space with rabbits, rodents or birds. It can become friends with a dog or cat only through careful, gradual, supervised introductions.

Heat is a particular danger

Ferrets cannot sweat, which makes them highly susceptible to heatstroke. PDSA recommends keeping their living area between 15 and 24°C and sheltered from direct sun, wind and rain. In summer, when the room warms up, shade, a fan and cooling tiles help, and the enclosure should never stand in a sunny window.

Vaccination, flu and travel

Canine distemper is nearly always fatal in ferrets, even with treatment, according to PDSA, so vaccination against it is a key part of preventive care. The Merck manual describes a primary course at roughly 8, 11 and 14 weeks of age, and PDSA recommends annual boosters in the UK; the exact schedule and the vaccine available are for a ferret-experienced vet to decide. Ferrets can also catch human influenza and pass it back, so an owner with flu should limit close contact. To travel to another EU country, a ferret – like a dog or cat – needs a European pet passport, a microchip and a valid rabies vaccination.

Neutering and hormonal health in females

A female that is neither spayed nor bred can stay in season for a long time, which the Merck manual links to a severe, oestrogen-related failure of the bone marrow. On the other hand, PDSA warns that surgical neutering in ferrets can increase the chance of adrenal gland disease later in life, which is why a hormone implant is used instead in some places. The right choice for an individual ferret is one to make with a vet.

Health risks in older ferrets

Tumours are relatively common in ferrets: VCA names insulinoma (a pancreatic tumour), adrenal gland tumours and lymphoma as the most frequent. Because early detection matters, VCA advises at least a yearly senior screening for ferrets over three years old. Weakness, hair loss, weight loss or changes in behaviour are all reasons to see a vet.

Scent and handling

Ferrets have a distinctive musky smell that is strongest in entire males. Removing the anal scent glands does not get rid of it, because the odour comes mainly from sebaceous glands in the skin; regular washing of bedding and a clean litter tray help far more. A ferret handled gently from an early age usually enjoys its owner's company, but it may nip when frightened or overexcited. Young children should meet a ferret at floor level and always with an adult watching.

A ferret does not belong in the wild

Never release a ferret outdoors. Escaped and released ferrets have formed feral populations in several countries, most extensively in New Zealand, where they threaten native wildlife, particularly ground-nesting birds.

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