Raising a baby weasel

The least weasel (Mustela nivalis) is our smallest carnivore, and its young weigh only a few grams at birth. When people find a baby weasel, they usually mistake it for a mouse or a young marten and do not know how to help it. Raising a baby weasel is one of the hardest tasks in wildlife care, so the most important thing here is to know when to leave the youngster alone and when to take it to experts straight away.

Weasels usually give birth in spring and early summer, in litters of four to six kits, sometimes more. The nest is hidden in a hole in the ground or in a pile of stones, wood or hay. The kits are born blind and naked, open their eyes at three to four weeks, and at around five weeks they start leaving the nest with their mother.

• The mother weasel often moves her young, carrying them one by one in her mouth. If you come across a kit on a path or in the grass, leave it where it is, move away, shut away dogs and cats and check again after a few hours. As a rule, the mother comes back.
• If you have already touched or moved the kit, put it back in the same place – the mother will take it.
• It needs help if the kit is cold and motionless, injured, covered in flies or fly eggs, if it was brought in by a cat, or if the mother has not come back even after a long period of watching.

A kit brought in by a cat should always be checked by a vet, even if you cannot see any wounds.

Because their bodies are so tiny, weasel kits lose heat very quickly. So:

• Pick the kit up with gloves or a soft cloth.
• Put it in a small plastic or cardboard box with soft fabric and air holes, and close it securely. Weasels can squeeze through incredibly narrow gaps, so ordinary cat carriers are not safe.
• Warm the box with a bottle of warm (not hot) water wrapped in a towel, on one side only, so the kit can move away.
• Never give a cold kit food or water. Warm it up first.
• Keep the box in a quiet, darkened room – no peeking and no cuddling.

Then call a wildlife rescue centre or vet straight away – a list of associations and rescue centres is available on our website. Wild animals in Croatia are protected by law and may not be kept at home without a permit.

For the first four to five weeks a baby weasel depends on its mother's milk, although the mother starts bringing it bits of prey earlier. An adult weasel is almost exclusively carnivorous and hunts mainly mice and voles.

• Never cow's milk – for such a small animal, diarrhoea and dehydration quickly become fatal.
• Experts use kitten milk replacer, but the type and amount should always be agreed with a vet or rescue centre.
• After weaning, a weasel needs whole prey, such as young mice, not just pieces of meat. Without the bones, fur and organs it does not get everything it needs to grow.

If the rescue centre asks you to feed the kit until they come to collect it:

• The kit must be warm.
• Feed it while it lies on its tummy, never on its back, because milk can end up in its lungs.
• Weasel kits suckle weakly, so the milk is given literally drop by drop, with a very small syringe without a needle or with a brush, pausing to let it swallow.
• Feeds are tiny and frequent; never force anything.
• After each feed, gently massage the tummy and the area under the tail with damp cotton wool to stimulate peeing and pooing.

Because of its tiny size and very fast metabolism, mistakes with feeding and temperature are especially dangerous here. That is yet another reason for the weasel to get into expert hands as soon as possible.

The weasel is an exceptionally fast and skilful hunter, and that is not something it can learn in a box in the living room. At a rescue centre, the kits grow up together with other young weasels, with minimal human contact, in an enclosure where they can dig, climb and hide. They are given food in different ways and at different times so they learn to search for prey.

A weasel that is used to people loses its wariness of humans, dogs and cats and does not survive long in the wild. That is why I advise you not to keep the kit even a day longer than necessary.

Young weasels develop very quickly: at around seven weeks they kill prey on their own, and at nine to twelve weeks they become independent in the wild. At a rescue centre they are only released once they hunt successfully on their own.

• Release is gradual, with an enclosure at the release site where they can acclimatise.
• The site must offer plenty of cover – hedgerows, dry-stone walls, piles of stones or wood – and enough rodents, and it must be far from roads and from settlements with lots of cats.
• Before release, their health, weight and behaviour are checked.

Weasels can carry fleas, ticks and intestinal parasites and, like other carnivores, theoretically rabies as well. Despite their small size, they bite hard. Do not touch the young animal with bare hands, wash your hands after any contact and keep pets away. If it bites you, rinse the wound with soap and water and see a doctor.

When you find a baby weasel, first give its mother the chance to find it. If it really is alone, cold or injured, warm it up, put it in a secure box and contact a wildlife rescue centre as soon as possible. Only then can this tiny but fearless predator grow up wild and return to nature.