Ferret

Page last updated: 27/04/2024

(Mustela [putorius] furo)

A ferret is so commonly mistaken for a wild animal that we feel it is important to first highlight a few basic facts: A pure ferret is not a European polecat, European polecat-ferret hybrid, or so-called black-footed ferret. They are domesticated animals that primarily depend on human care to survive. Much of the confusion between these wild and domesticated mustelids appears to be due to both visual misidentifications and a broad use of the term ferret. There is practically not a single mustelid within the subfamily Mustelinae that has not somehow been misidentified or mislabelled as this animal.

A ferret is wildly believed to be the domesticated form of the wild European polecat, perhaps even a crossbred with the steppe polecat. A ferret is to the European polecat like the dog to the grey wolf. The ferret’s Latin name has been traditionally Mustela putorius furo, but some mammalogists are moving towards naming them simply Mustela furo, to further distinguish them from their wild ancestor.⁽¹⁾The American Society of Mammalogists classify the ferret as a distinct species,⁽²⁾ though this decision may be disputed by some authors.

There are two recognised breeds of ferret—the short or mid-haired ferret (also known as the the standard ferret) and the rarer Angora ferret.⁽³⁾Ferrets are increasingly found around the world in homes as dependent pets. In certain parts of Europe (particularly Britain), some are still used as hunting companions to simply flush rabbits out of their burrows—a practice known as “rabbiting” or “ferreting”.⁽⁴⁾

Having a ferret as a pet is neither strange nor misguided, as some will claim. Some people are simply misinformed about their behaviour due to overgeneralising, while others criticise their smell. The latter is due to their anal gland secretions, and male ferrets in particular (especially those which are unneutered) can smell almost as musky as an unwashed human, but that does not mean they cannot make good pets given proper care. Like many underrecognised domestic animals, ferrets have come a long way in recent years proving that dogs and cats are not the only treasured four-legged household companions.

Appearance

Ferrets have been bred for a large variety of fur colours. The eight basic colours are: Albino, black, black sable, champagne, chocolate, cinnamon, dark-eyed white, and sable. By far the most common of these colours is sable (not to be confused with the animal sable, which is a species of marten). There are also many ferret patterns: Masked, bib, stocking, self (milkmouth), marked, blaze, mitt, panda, point, roan, and solid.⁽³⁾⁽⁵⁾

Angora ferrets can be distinguished from standard ferrets by the extra fold in their nose, generally with a tuft of fur outside, inside, or covering the nose. Their undercoat is the same length as their overcoat and is longer than a standard ferret’s, measuring 5-12.7 centimetres (2-8 inches) long.⁽³⁾ Both breeds of ferret are sexually dimorphic, with males being larger than females.⁽⁶⁾

Confusion with the European polecat

Ferrets tend to be confused with European polecats. While they can look very similar, there are often a few ways to tell the difference between the two. This overview focuses on the differences between European polecats and ferrets in the UK specifically.

Much like European polecats, ferrets have two annual moults: one in spring and another in autumn. In summer they both have darker, shorter fur than their winter counterparts. This can make a ferret with a sable colouration difficult to distinguish, and it is important to note that in this case pelage identification methods alone are not 100% guaranteed.⁽⁷⁾

A European polecat’s nose is usually solid black, while a ferret’s tends to be pink, speckled, or dark brown. A ferret’s nose can also be solid black, but this tends to be less seen. The ferret’s skull has a smaller cranial volume as well as a narrower postorbital constriction (indents behind the eye sockets).⁽⁸⁾ In addition, the ferret is slower in all its movements compared to the European polecat, and hardly makes any use of its anal scent glands.⁽⁹⁾Ferrets overall represent a neotenous form of European polecat.⁽¹⁰⁾

Furthermore, sable ferrets have dark fur on their face which typically does not reach the nose. Their pale cheek patches and frontal band are usually large and contrast poorly with the darker facial mask. Scattered white guard hairs cover the body, particularly the hindquarters and tail. Throat patch is 50mm (2 in) or longer. They tend to have one or more white paws.

Meanwhile typical European polecats have dark fur on their face that extends to the nose. Pale cheek patches and a possible frontal band contrast with a dark facial mask. No scattered white guard hairs over the body. No throat patch, or less than 50mm (2 in) in length. Dark fur covers the paws.⁽⁷⁾

Behaviour

Ferrets are by nature very playful and social. While their wild European polecat counterparts are mostly solitary, ferrets exhibit neoteny, including playfulness and (in most cases) the desire to interact with their owners and other ferrets. To not overgeneralise their behaviour, it is worth mentioning that some ferrets seldom interact with their owners and other ferrets, or prefer giving attention to one over the other. Just because ferrets are considered sociable animals that does not necessarily mean they want to be sociable with everyone.

Ferrets tend to be extremely inquisitive and show very little of the cautiousness that you would see in a wild European polecat, so it is important to “ferretproof” any areas that they are allowed to play in—they can, and will, get into any space that they can squeeze into, which is why most ferret owners choose to house their ferrets in a cage (preferably one with multiple levels and plenty of room). Ferrets kept in cages should have a bare minimum of two hours (more is recommended and depends on the ferret) outside of the cage each day, since they are very active and energetic when awake.

Playing

Most ferrets love to chase and pounce on dangling toys, rolling balls, etc.—cat toys tend to work very well as ferret toys. Some ferrets can be taught to respond to their names and can learn tricks just like dogs, but this requires a tremendous amount of patience because they have short attention spans and are very easily distracted. An excited and happy ferret will bounce about with its back arched and its mouth wide open, waving its head around, bumping into things, and “dooking”—a sound somewhat similar to a hen clucking. Ferret enthusiasts have named this behaviour “the weasel war dance”. Some people unfamiliar with ferrets have misinterpreted this display as aggressiveness or an attack, but it is actually an expression of pure excitement and playfulness.

Socialising

Because of their playful and social nature, most ferret owners opt for more than one ferret so that they can play and wrestle together. Some adult ferrets can be happy as a single pet, so long as their owner(s) is home often to provide them with adequate attention. This is not recommended for ferrets that are used to having other ferrets as playmates, since not only can they become quite attached to other ferrets, they can also become understimulated even with human companionship. An understimulated ferret can become destructive, tearing up objects in their cage, and biting on the bars.

In some cases, owners have added another ferret to their family in hopes of giving their single ferret a playmate, only to find out that they do not get along and end up with two separate pets (we have been there). In this situation, try washing and replacing all bedding and then give them a bath together to neutralise scents. The results are not immediate or guaranteed, and may take several weeks for them to “work it out”. During this time it is best to keep them in separate cages and have only short and supervised playtime until relations improve. Swapping their hammocks may also help. At the end of the day, similar to us humans, ferrets are not perfect carbon copies of one another—most prefer the company of other ferrets but some do not. Please do not force these ferrets to socialise if it is not necessary.

Ferrets have an undeserved reputation for being nippy and aggressive, but a properly socialised ferret will not bite hard out of fear or aggression. Most love to wrestle and play rough with each other, including dragging each other around with their jaws, so they simply need to be taught not to play quite so rough with their human owners. Most ferrets are able to learn this pretty quickly with proper training. Some improve after the owner scolds or hisses when they get too rough, others are better at responding to being placed in time out for 5 minutes or being ignored after a bite—teaching the ferret that biting results in the opposite of what they want, which is usually attention. If successful, they will still most likely continue to use their mouths when they play, but they will not actually bite. Ferrets can be wonderful pets for the person who has the proper amount of time to dedicate to interacting with them. Some can even be trained to use a litterbox, though even the most experienced ferret will occasionally have accidents.

They have unique “personalities”

While there is a lot of good advice out there on how to properly train or care for a ferret, the truth is a lot of information can be overgeneralised and even emotion-based nonsense. This is because a ferret’s needs can differ depending on age, personality, and individual taste. Never assume that any ferret you obtain will have the same personality or needs as other ferrets you or someone else has had or have. It is best to avoid even assuming all ferrets deal with stress or trauma the same.

Reproduction

Most female ferrets are already spayed upon purchase from a pet store, so this section only concerns intact females.

Female ferrets are seasonally polyoestrous, which means they have multiple oestrous cycles during the breeding season. The breeding season starts around March in the Northern Hemisphere and October for Antipodeans. Females reach puberty around 8 to 12 months of age. If they are not bred, they exhibit a constant oestrus (also referred to as being in heat) for up to 5 months. At the beginning of this stage, there will be increased swelling of the pink-coloured vulva. It is important that the female be taken out of season, otherwise she could die from aplastic anemia.⁽¹¹⁾

While this can be be done by breeding them, this is not recommended by some ferret caretakers. Safer alternatives include the “Jill Jab”, which is a hormonal injection given once each heat cycle to bring them out of heat. This may be followed up with surgical sterilisation (spay) or chemical sterilisation with a Suprelorin F (deslorelin acetate) implant. Another option is mating with a male that has had a vasectomy (v-hob).⁽¹²⁾

If a female is bred with an intact male, once ovulation is induced, either pregnancy or pseudopregnancy follows. The gestation period is 41 days (39-42 days). The female gives birth to an average of eight kits (1-18 kits) which weigh 6–12 g (0.2–0.4 oz).⁽¹³⁾

Diet

Ferrets are obligate carnivores, which means they must eat meat. They have a short intestinal tract and absorb nutrients inefficiently, which is one of the reasons their diet needs to be high in meat based protein, have no sugars, and little to no carbohydrates. If choosing to feed them dry food (kibble), it is recommended that it contains at least 36% protein that is moderate in fats (approximately 20%) and low in carbohydrates.⁽¹⁴⁾

Health and welfare

The ferret is known to be affected by several distinct health problems, especially those which were poorly bred in North America. They are susceptible to cancers affecting the adrenal glands, pancreas, and lymphatic system, as well as several other diseases. It is believed the reason for many of their health problems is due to a lack of genetic diversity, which stem from inbreeding to achieve human-desired traits such as coat colour and temperament.⁽¹⁵⁾ Other probable factors include being weaned before they are of proper age or neutered before sexual maturity is reached.⁽¹⁶⁾These practices are most often performed by ferret mills and backyard breeders, rather than reputable breeders. Most people will purchase a ferret from a chain pet store and odds are they came from a ferret mill.

Due to many of these health issues, as they age, poorly bred ferrets can become expensive pets. Given that ferrets are often thought of as simple “pocket pets” the cost of health care can come as a surprise for many first-time ferret owners. People of modest means should take this into consideration before purchasing multiple (as in greater than two) ferrets. It is important to care for these animals by annually taking them to the veterinarian for checkups and dental cleanings (the latter if fed kibble rather than raw meaty bones), as well as pay for prescribed medication (if needed), and occasionally life-saving surgeries.

Lastly, while there are many experienced veterinarians in the world, not all are qualified or experienced in treating “exotic” animals like ferrets. So it is also a good idea to check for the appropriate credentials of local veterinarians, as well as references. Regardless of how they were bred, like any dog or cat, ferrets require years of commitment and should not be an impulse buy.

Regarding ferret care in California

Even though ferrets are illegal to have as pets in California, it is unrealistic to believe people who love them will not take the risk to own them. And of course, no one moving to the state would want to give up their pet either. So the law does little beyond discourage some ferret owners from seeking veterinary care within the state, in fear of their ferret being confiscated. Thankfully, there are some ferret-friendly vets in California, but one has to do their research.

SARS-CoV-2

Since ferrets and humans share a similar upper and lower respiratory tract⁽¹⁷⁾ they are suitable to SARS-CoV-2 and can develop a fever, lethargy, and cough. Currently, there is no credible evidence supporting that infected ferrets can spread the virus to humans or vice versa, and ferret-to-ferret transmission has only been reported to occur in experimental settings.⁽¹⁸⁾⁽¹⁹⁾Research is ongoing, and generalisations about the spread of COVID-19 in ferrets should be avoided.

Ferrets are not wild animals

Ferrets are banned as pets in some parts of the world. In some states and cities in United States this is in part due to outdated technicalities, and the unsupported presumption that escaped or abandoned ferrets are a threat to agriculture and wildlife. This is despite the often disregarded truth that other permitted pets such as dogs and cats are a far greater ecological threat than ferrets when they become feral or are simply free-ranging.⁽²⁰⁾⁽²¹⁾ We do not suggest banning dogs and cats, of course, but is it important to point out the inconsistent treatment of these domesticated animals. There is also a faulty generalisation that ferrets behave the same as wild native weasels, or the European polecat and European polecat-ferret hybrid of Europe.

Ferrets have been domesticated for over two-thousand years,⁽²²⁾ and unlike their wilder counterparts, they have lost much of their natural instincts and are unlikely to have self-sustaining populations in North America. The fact that many of these ferrets have been spayed or neutered, are often more curious than cautious when it comes to danger such as predators, are very uncoordinated and clumsy, and prone to heat exhaustion makes survival and colonisation even less likely. This is also an animal one has to tidy their home for because some will try to eat small inedible objects which can lead to intestinal blockages, or climb and jump from high places and injure themselves. They can barely survive unsupervised in a house. This is by no means to say ferrets are not intelligent animals, but most today were bred to be suited to a carefree life as a household pet and are not renown for their survival skills.

Ferrets have been legal as pets in most US states and Canadian provinces for decades, and by now we would have seen more evidence of impending ecological disruption if this were likely. According to the American Ferret Association, a ferret would not be capable of surviving in the wild for more than a few days before succumbing to the elements or starvation.⁽²³⁾ If you spot a ferret wandering about unattended (especially in North America), it likely either recently strayed away from its owner or was irresponsibly released. Please call your local animal control officer ASAP.

Hybridisation (North America, Europe, and New Zealand)

In North America, it is highly improbable that a ferret will hybridise with a wild animal, since there are no other closely related (or reasonably accessible) species to hybridise with. Though related by subfamily, the North American mink, least weasel, long-tailed weasel, North American stoat, Haida stoat, and Eurasian stoat in North America are not known to be genetically compatible to ferrets for natural hybridisation to occur. It is unclear if ferrets can hybridise with the North American polecat (a.k.a. black-footed ferret), but they would have little chance of ever coming into contact with one, let alone survive in their harsh environment.

Heads of a 1) European polecat, 2) ferret, and 3) European polecat-ferret hybrid. Source: Journal of Genetics, Vol. XI, No. 2. Larger image

Although the odds are still against them, in parts of Europe (particularly the British Isles) escape and abandoned ferrets have been known to survive long enough to hybridise with the native wild European polecat.⁽²⁴⁾However, it is the European polecat-ferret offspring from this hybridisation that has the better potential to be self-sustaining. There are no reproductively self-sustaining pure ferrets in the wild.

In New Zealand, European polecat-ferret hybrids were introduced to the island the late 1800s.⁽²⁵⁾ To this day, they are commonly and misleadingly simply called “ferrets” in the country, which only perpetuates the misbelief that pure ferrets are wild animals. More officials should make it clear to the public that a European polecat-ferret hybrid is not the same as a pure ferret one often buys at a pet store.

Differences between pure ferrets and European polecat-ferret hybrids

European polecat-ferret hybrids tend to have better eyesight, greater physical capabilities, and are more independent in nature than pure ferrets. However, they are likely less willing to be handled or familiarise themselves with dogs, may refuse to enter unfamiliar burrows, require much attention in order to prevent boredom, are more likely to kill their quarry rather than simply flush them from their burrow, and do not cope well with being caged.^(26)(27)

Misrepresentations in media

Some might label us as “pro-ferret” for the statements below, and thus bias. However, we are not so much pro-ferret as we are supporters of responsible pet ownership.

Claims of threats to human safety

There is lot of sensationalism and scaremongering surrounding the temperament of ferrets, some of which are exacerbated by politics and mislead opposers of these animals who presumably have no long-term experience caring for them. The fact is, when properly socialised, ferrets are mostly gentle pets that are no more aggressive or dangerous than your average domesticated dog or cat. Some opposers have mentioned reports of infants and toddlers being injured by a pet ferret,^(28)(29)(30) but similar injuries and even deaths have occurred regarding various common breeds of domestic dogs.^(31)(32)(33) Yet anecdotally, we rarely hear anyone generalising dogs as dangerous pets. Perhaps this is because many more people are familiar with dogs, and (like many ferret owners) understand that dogs of even the same breed do not all behave exactly the same.

Typically, these types of incidents involving ferrets are isolated cases of parental negligence or owner irresponsibility and should not be generalised as a common experience. It is possible some of these cases were simply ferrets escaping from their cages, but adequate housing is not the ferret’s responsibility. It is also important to consider that, in other cases, children may not realise they could be irritating or hurting a pet (e.g., pulling on their tails). Animals and most children cannot speak for themselves, and it is hard to say whether or not we always get the full story when it comes to incidents involving children and small pets.

This should not be assumed as trying to blame the victim, but rationally seeking all the facts before making sweeping generalisations. We must emphasise this, because there are people who will hastily denounce any criticism deemed less-than-empathetic, sometimes to simply placate or appease public fear—which often deflects attention away from the root of the problem and discussing practical solutions. Ultimately, we would argue that no pet is guaranteed to be safe for infants and toddlers, especially if they are left together unsupervised.

As with any dog or cat, how a domesticated animal was bred, socialised, housed, or cared for should always be taken into consideration. There should not be a double-standard to this rule when it comes to ferrets. There are likely millions of ferrets kept as household pets in the United States alone.⁽³⁴⁾Rather than try to demonise a popular pet by fixating on worst case scenarios, we should instead focus more on awareness regarding childhood risks, as well as teach the importance of parental and owner responsibility.

They are sometimes falsely accused of attacks or damage to property

In other cases, due to misleading content on the internet, ferrets can be falsely accused of attacks on domestic animals and wildlife or damage to property that is typically performed by a different relative. For example, there is a German video on YouTube that attempts to explain how the beech marten damages automobiles in Europe.⁽³⁵⁾ However, clearly in the video the mustelid being shown is a ferret and not a beech marten. Unfortunately, it is this type of staged and misleading content that gets taken at face value by people unfamiliar with ferrets, and needlessly makes it more difficult to educate the public about these animals.

Genuine Mustelids

Serving to promote a more accurate representation of mustelids in media.