Wild rabbits

The European Rabbit

 

Scientific classification

Etymology

Distribution and domestication

Characteristics and behaviour of wild rabbits

 

Scientific classification


Domestic rabbits are descended from the wild European rabbit (Oryctolagus cuniculus). Rabbits are lagomorphs, along with hares, and pikas.

Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Lagomorpha
Family: Leporidae
Genus: Oryctolagus
Species: Oryctolagus cuniculus

Etymology

‘Oryctolagus’ – from Ancient Greek ὀρυκτός (oryktos) meaning ‘dug up’ and λαγώς (lagōs) meaning ‘hare’.

‘Cuniculus’ – the Latin name for rabbit, from Ancient Greek κύνικλος (kýniklos), meaning ‘burrow’.

Distribution and domestication

The European rabbit (Oryctolagus cuniculus) is native to Spain and Portugal (the semi-arid regions), and north Africa (Morocco and Algeria). Thanks to humans, wild rabbits are now found widely throughout Europe. They were also introduced in Australia, New Zealand, Chile, and the Falkland Islands.

European rabbits, brown hares (Lepus europaeus), and mountain hares (Lepus timidus) are all found in Britain. Brown hares were introduced, but the mountain hare is a native lagomorph. The European rabbit is not indigenous to Britain – evidence suggests they existed in pre-glacial Britain, but died out during the last Ice Age, which means rabbits are an introduced species.

A fragment of a rabbit tibia bone, unearthed at Fishbourne Roman Palace, West Sussex, during an archaeological dig in the 1960s, was recently radiocarbon dated to be almost 2,000 years old. The rabbit had probably been kept as an exotic pet. In 2005, remains of a 2000-year-old rabbit dinner were found, by archaeologists excavating a Roman settlement at Lynford, Norfolk. It seems the Romans imported domesticated rabbits from Europe, but the species does not seem to have established in the wild in Britain. There is no mention of rabbits in the Domesday Book – the earliest mention of a rabbit warren is from 1176, on the Scilly Isles. There are records from about AD 1235 of rabbits in a royal park at Guildford, Surrey, belonging to King Henry III, and rabbits appeared on banquet menus at around this time. There are records of King Henry ordering the sheriffs and bishops of cities to supply rabbits from maintained colonies – ‘cuningera’ or ‘coneygarths’. It’s likely that rabbits escaped during these journeys and established themselves in the British countryside.

So, as far as we know, rabbits have been established in Britain for just under 900 years.

Today, there is a wide range of domesticated breeds, selectively bred to suit humans’ needs, whether those are to produce rabbits suitable for pets, to be displayed at shows, or to be used for food. Most are much larger than their wild ancestors, with a variety of fur colours and patterns, and many have flatter faces and lop ears.

Rabbits are one of the most recently domesticated animals. Aside from selective breeding and their tolerance of humans, the characteristics and behaviour of domestic rabbits have remained very similar to those of wild rabbits. Therefore, it’s important to find out about the life of the wild European rabbit, to help us provide the best welfare for our domestic rabbits.

Characteristics and behaviour of wild rabbits

Nature: Rabbits are prey animals, and every aspect of their life is adapted to this nature – including their physiology, habitat, diet, activity, and communication. They are prey for around 50 species, including foxes, stoats, weasels, badgers, birds of prey, wildcats, and domestic dogs and cats. They can be attacked by predators on the ground, under the ground, or from the sky, so are easily frightened by strange or sudden sights, sounds, and smells. They are constantly alert – if they sense danger, they will freeze, and may thump the ground with their hind legs to alert other rabbits; if danger approaches, they run at high speed to a known bolthole. If there’s no escape, rabbits will fight. Our domestic rabbits retain many of the behaviours and needs of a prey animal, although their ‘fight or flight’ response is not as strong.

Appearance: Males (bucks) and females (does) are similar in appearance, although does tend to be smaller than males, with slightly narrower heads. They grow to a length of 34-50cm (head and body), with a 4-8cm tail, and weigh about 1.2-1.5kg. Their coat is greyish brown on the back, with a pale grey-white tummy, and paler ginger area on the nape. Their tail is darker on the top, with a white underside. Although this is the normal appearance, some rabbits are a sandy yellow in colour, and some are completely black (of course, our domestic rabbits’ appearance is very different from this). Rabbits are easily distinguished from hares – they are significantly smaller, and their ears and hind legs are much shorter, proportionally (rabbits’ ears are shorter than their head length). Hares also have black tips to their ears.

Rabbits use their powerful hind legs to hop, rather than walk. They can make a lateral leap of about 10 ft in one bound, and they can reach speeds of over 50 miles per hour if they need to escape a predator. Their hind feet are padded with fur to absorb shock, and their long toes are webbed to prevent them spreading and breaking during movement. Their feet are designed so the claws sink into the ground (an important factor when considering the flooring in our rabbits’ home).

Ears: Rabbits’ hearing is essential for their survival. They can hear sounds from different directions simultaneously, as their ears can move independently, helping them to detect danger.

Eyes: As a prey species, rabbits rely on their excellent, near 360-degree field of vision (they do have two blind spots: in front of their nose and directly behind their head). Their eyes are situated high on the sides of their faces. Rabbits sleep with their eyes open, and blink their nictitating membranes (third eyelids) to keep their eyes moist.

Nose: Rabbits are obligate nasal breathers – breathing only through their noses enables them to smell danger, even when eating.

Communication: Although generally quiet, rabbits can make a variety of sounds to communicate, including growling, purring (teeth gently grinding), honking, and screaming if in extreme pain or fright. They thump the ground with their back legs to signal danger. They can also communicate using posture (body, ears, and face).

Scent marking is an important aspect of rabbit communication – it denotes territory, helps to deter intruders, and reinforces hierarchy. It can communicate a rabbit’s sex, age, reproductive status, social status, and group identity. Scent is deposited using the scent glands (under the chin), droppings, and urine. The dominant buck in the group has the best developed scent glands and will conduct most of the scent marking. Rabbits rub their chin on prominent objects within their territory, and even over other rabbits! During courtship, bucks sometimes spray urine at does. Females also scent mark – especially at the entrance to their nest.

(Domestic rabbits use the same methods of communication – see our page on Behaviour).

Habitat, territory, and hierarchy: As prey animals, wild rabbits like to have cover nearby, but can be found in a wide variety of habitats – deciduous woodland, grassland, heathland, meadows, farmland, and even sand dunes. Their warrens may be dug to 3m deep and cover a large area. The many entrances lead to a network of interconnecting burrows, with living quarters and nesting chambers. Rabbits may range as far as a couple of acres – the bucks tend to go further than the does. The dominant bucks will establish the territory and defend it against rabbits from other colonies. They mark the boundary by spraying urine, leaving droppings (which may be coated in a scented mucus from anal glands), and by rubbing their chin along items (to scent from the gland under their jaw).

Rabbits are extremely sociable and live in colonies, with up to 50 individuals, divided into groups of between 2-10 closely bonded rabbits. Rabbits forage in these small groups, which helps them to stand a greater chance of spotting predators – at least one rabbit is always alert for danger.

The adults maintain a hierarchy, with the more dominant rabbits having first choice of food, burrow, and choosing who grooms them. The dominant doe will fight other does for the best nesting chamber, which is usually near the centre, safer from predators. Subordinate rabbits socialise with other subordinates, and do not establish a territory.

Activity: Rabbits remain active throughout the year (they don’t hibernate). They are crepuscular – they are most active above ground at dawn and dusk. They may also emerge at night, but spend most of the daylight hours in their warren. They may be spotted out during the day, especially if it’s sunny, warm, and safe, but spend most of their time in dark or low light, so do not enjoy bright light.

They spend about 70% of their awake time eating, most intensely between 5pm and midnight. Rabbits graze close to their warren, so they can run for cover if necessary, and are always alert for predators. They stand on their hind legs, often on an elevated area (e.g. fallen tree trunk) to look out for danger, using eyes, ears, and noses. If they sense danger, they will warn others by thumping with a hind foot. They may freeze to reduce their visibility, but if they choose to run for cover, the white under their tail also signals a danger alarm to other rabbits.

They eat their caecotrophs in the safety of their warren, but deposit their hard, dry droppings in a latrine above ground.

Rabbits clean themselves regularly using their teeth, tongue, and paws.

Diet, teeth, and digestive system: Rabbits are herbivores and can eat a wide range of vegetation – grasses, clovers, a variety of green plants, bark, some roots, and, of course, crops.

Their teeth and digestive systems have developed to cope with their diet of poor quality, high fibre vegetation. Rabbits use their razor-sharp front incisors to bite through stems, and their back molars to grind down the food – they have a chewing action of around 120 bites per minute. They have 28 teeth, and these are open-rooted teeth, growing continuously throughout a rabbit’s life. Their incisors (front teeth) grow 2-3mm per week; their molars (back teeth) grow 2-3mm per month. Without the correct diet (i.e. 85-90% grass/hay), the teeth can soon overgrow, causing many problems. (Rabbits have just one set of teeth during their lifetime, unlike many species (e.g. humans, dogs, and cats), which have the deciduous teeth (baby teeth), replaced, when they fall out, by adult teeth).

The cell walls of most plants are composed principally of cellulose, which digestive enzymes of mammals are unable to break down. To extract all the nutrients from their diet, rabbits have a complex digestive system. After chewing and swallowing food, some nutrients are absorbed as the food passes through the stomach and small intestine. The partially digested food will then move on to the large intestine, which is split into a fermenting chamber (caecum) and the colon leading to anus. In the caecum, partially digested food undergoes hindgut fermentation: it is mixed with bacteria, yeasts and other micro-organisms which digest cellulose and turn it into sugar.

The food remains are separated into digestible and indigestible parts. The indigestible food helps the rabbit’s gut to keep moving, by peristalsis. It moves through the digestive tract, and is excreted as hard, fibrous faeces. The digestible part of the food material will stay in the caecum (or re-enter the caecum if it’s reached the colon) for further fermentation, for up to 4 hours, to digest as many nutrients as possible. The contents of the caecum pass into the colon, and are excreted as soft, moist pellets, which are coated in mucoprotein and rich in vitamins and microorganisms – caecotrophs. These are eaten directly from the anus by the rabbit, as they are produced. It’s essential that rabbits consume them, to keep in good condition. They are swallowed whole, without chewing. This keeps the mucus layer that coats the pellet intact, so that the good bacteria inside isn’t broken down too quickly by the stomach acid. The vital nutrients are extracted from the caecotroph as it is broken down by fermentation in the stomach and small intestines. After this, they pass out as hard faecal pellets. Rabbits can produce 200-300 of these daily.

Reproduction: Rabbits have a reputation for their prolific breeding, hence the expression ‘to breed like rabbits’. Their numbers are usually kept in check by predation and other risks such as road traffic, disease, and shooting. Bucks reach sexual maturity at around 4 months. Does can become pregnant when they are around 12 weeks old and can conceive at any time of year (although they breed mainly in spring and summer, due to climate and food availability). They build a nest of grass and straw, usually in a dead-end burrow, then pull out their fur to line it. They have a gestation period of 28-31 days, and the average litter size is 6, although there can be up to 14 kittens (baby rabbits – also known as kits). New-born kits weigh about 30-35g, and are altricial – hairless, blind, and deaf. The doe’s milk is very rich, so the kits only need to nurse twice a day, for only a few minutes each time, usually at dawn and dusk. This helps to reduce the chance of predators finding them. At 8 days, they usually have fur, and by day 10 their eyes are open. After a fortnight, they emerge from the burrow. The kits are fully weaned at around 4-6 weeks old.

Rabbits can become pregnant straight after giving birth, meaning that they could produce up to 13 litters per year. (This is why it’s so important to ensure baby domestic rabbits are sexed properly, and that rabbits are neutered!).

Disease: Myxomatosis, a virus mostly spread by insect vectors (mosquito and flea), was intentionally introduced to the wild rabbit population in the mid 1950s, to control the booming rabbit population, which was causing extensive damage to crops and trees. The onset of myxomatosis symptoms, which affect the eyes and brain, is rapidly followed by death, and Britain’s rabbit population plummeted by over 95% in just a couple of years.

This had other impacts – there was a decline in various rabbit predators (especially foxes and buzzards), and changes to vegetation, such as the growth of unwanted plants. The rabbit population had recovered by the mid 1990s, with an estimated 50 million rabbits living in Britain, but it is now, once again, in decline (by around 60% since the mid 1990s), due to Rabbit Viral Haemorrhagic Disease (RVHD). This highly infectious disease, first reported in China in 1984 but now endemic in most countries, has high mortality rates. The virus survives on the ground for days. A new variant is now sweeping through the rabbit population.

Longevity, mortality, and conservation: On average, wild rabbits may live for 3-4 years, although many die within their first year – mortality rates can be as high as 75% for the first 3 months, 95% for the first year. Numbers are reduced by predators, but also by disease, agricultural developments, climate (which affects food availability and habitat), and hunting/poisoning by humans. European rabbit numbers have dropped, especially in native countries – it has most recently been assessed for The IUCN Red List of Threatened Species in 2018. Many countries are now working to conserve the European rabbit, focusing reducing the impact of disease, protecting habitat, and reducing the impact of humans on their numbers. (Note – many domestic rabbits are able to live into their teens, thanks to advances in welfare knowledge and rabbit medicine).

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