Normal Size & Weight Of An Adult Ferret

Domesticated ferrets have become common house pets in the United States and Canada, though not all U.S. states permit these types of weasels as pets thanks to invasive species concerns. The wild black-footed ferret, once believed to be extinct, is the only ferret species native to North America and looks a lot like its domestic counterpart. Most ferrets found at pet stores are descended from the European polecat, a species of mustelid, domesticated more than 2,000 years ago to hunt vermin.

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Polecats measure approximately 12 to 18 inches in length. Male polecats weigh about 2 to 4 pounds, and females weigh about 1 to 2.5 pounds. Domestic ferret size is similar to their polecat ancestors. However, full-grown ferret weight is usually slightly heavier thanks to a better diet in captivity and more access to food.

Domestic ferrets are long and slender, similar to other types of weasels. The most common colors are white with pink eyes, sable, cinnamon, and chocolate. Often, they have brown coloring around the eyes, making them look like mischievous bandits wearing masks. Female ferrets are usually about 12 inches long, and male ferrets are about 16 inches in length.

Ferrets are considered adults by 1 year old but can reach adult size earlier. Males are slightly larger and longer than females. Male ferrets have a larger, rounder head than females, and a healthy adult male ferret, called a hob, should have more body muscle than a female. Male ferrets usually weigh about 4 pounds when unfixed and about 2.5 pounds when neutered.

Conversely, the full-grown ferret weight of a female is slightly less than a male. The female ferret, called a jill, has a narrower head than a male and a thin, pointy nose. Full-grown female ferret weight is about 2.5 pounds when not spayed or 1.75 pounds when fixed. Ferrets should be spayed or neutered between 6 and 12 months old because once females come into heat, they stay in heat until mated.

Very young ferret size is small. Ferrets younger than 1 year old are considered juveniles, and baby ferrets are called kits. Kits are born very small at about 2 inches long. They are weaned by 8 weeks old and then grow rapidly. Baby ferrets reach full size at 5 to 6 months old and typically have a life span of six to 10 years.

Young ferrets reach full size very quickly, so a juvenile ferret will look like an adult often by 4 months old. A young, healthy ferret should have a glossy coat and be bright, alert, and active. They should be adult size at the point of adoption but are likely not yet sexually mature. Sexual maturity in ferrets occurs the first spring after they are born. Males can become aggressive and territorial after this time.

Ferrets are actually types of weasels and not rodents like some people think. As members of the weasel family, they have unique requirements, especially as pets. Ferrets are carnivores and require meat in their diet to achieve and maintain optimal weight. In the wild, ferrets eat whole prey, such as mice and rats, but in captivity, they should be fed highly digestible meat proteins and fats, such as chicken. Avoid grains because ferrets cannot digest fiber.

They are very active, social creatures who require multilevel habitats with stairs and ramps, hammocks to curl up in, and interaction with others, especially other ferrets. It's recommended that you keep them in pairs but have them fixed by a veterinarian. Like many types of weasels, ferrets can have a musky smell, which reduces after neutering.