WILD BOAR

Facts

The Wild Boar is a bulky, massively built suid with short and relatively thin legs. The trunk is short and robust, while the hindquarters are comparatively underdeveloped. The region behind the shoulder blades rises into a hump and the neck is short and thick to the point of being nearly immobile. The animal’s head is very large, taking up to one-third of the body’s entire length. The structure of the head is well suited for digging. The head acts as a plough, while the powerful neck muscles allow the animal to upturn considerable amounts of soil: it is capable of digging 8–10 cm (3.1–3.9 in) into frozen ground and can upturn rocks weighing 40–50 kg (88–110 lb). The eyes are small and deep-set and the ears long and broad. The species has well developed canine teeth, which protrude from the mouths of adult males. The medial hooves are larger and more elongated than the lateral ones and are capable of quick movements. The animal can run at a maximum speed of 40 km/h (25 mph) and jump at a height of 140–150 cm (55–59 in).

Sexual dimorphism is very pronounced in the species, with males being typically 5–10% larger and 20–30% heavier than females. Males also sport a mane running down the back, which is particularly apparent during autumn and winter. The canine teeth are also much more prominent in males and grow throughout life. The upper canines are relatively short and grow sideways early in life, though they gradually curve upwards. The lower canines are much sharper and longer, with the exposed parts measuring 10–12 cm (3.9–4.7 in) in length. In the breeding period, males develop a coating of subcutaneous tissue, which may be 2–3 cm (0.79–1.18 in) thick, extending from the shoulder blades to the rump, thus protecting vital organs during fights.

Adult size and weight is largely determined by environmental factors; Boar living in arid areas with little productivity tend to attain smaller sizes than their counterparts inhabiting areas with abundant food and water.

The winter coat consists of long, coarse bristles underlaid with short brown downy fur. The length of these bristles varies along the body, with the shortest being around the face and limbs and the longest running along the back. These back bristles form the aforementioned mane prominent in males and stand erect when the animal is agitated. Colour is highly variable and coat colour also varies with age, with piglets having light brown or rusty-brown fur with pale bands extending from the flanks and back.

The Wild Boar produces a number of different sounds which are divided into three categories: Contact calls – Grunting noises which differ in intensity according to the situation. Adult males are usually silent, while females frequently grunt and piglets whine. When feeding, Boar express their contentment through purring. Studies have shown that piglets imitate the sounds of their mother, thus different litters may have unique vocalisations. Alarm calls – Warning cries emitted in response to threats. When frightened, the Boar makes loud huffing ukh! ukh! sounds or emit screeches transcribed as gu-gu-gu. Combat calls – High-pitched, piercing cries.

Boar are typically social animals, living in female-dominated sounders consisting of barren sows and mothers with young led by an old matriarch. Male Boar leave their sounder at the age of 8–15 months, while females either remain with their mothers or establish new territories nearby. Subadult males may live in loosely knit groups, while adult and elderly males tend to be solitary outside the breeding season.

The breeding period in most areas lasts from November to January, though most mating only lasts a month and a half. Prior to mating, the males develop their subcutaneous armour in preparation for confronting rivals. By the end of the rut, males are often badly mauled and have lost 20% of their body weight, with bite-induced injuries to the penis being common. The gestation period varies according to the age of the expecting mother. For first-time breeders, it lasts 114–130 days, while it lasts 133–140 days in older sows. Farrowing occurs between March and May, with litter sizes depending on the age and nutrition of the mother. The average litter consists of 4–6 piglets. The piglets are whelped in a nest constructed from twigs, grasses and leaves. Should the mother die prematurely, the piglets are adopted by the other sows in the sounder.

Newborn piglets weigh around 600–1,000 grams, lacking underfur and bearing a single milk incisor and canine on each half of the jaw. There is intense competition between the piglets over the most milk-rich nipples, as the best-fed young grow faster and have stronger constitutions. The piglets do not leave the lair for their first week of life. Should the mother be absent, the piglets lie closely pressed to each other. By two weeks of age, the piglets begin accompanying their mother on her journeys. Should danger be detected, the piglets take cover or stand immobile, relying on their camouflage to keep them hidden. The neonatal coat fades after three months, with adult colouration being attained at eight months. Although the lactation period lasts 2.5–3.5 months, the piglets begin displaying adult feeding behaviours at the age of 2–3 weeks. The permanent dentition is fully formed by 1–2 years. Sows attain sexual maturity at the age of one year, with males attaining it a year later. However, oestrus usually first occurs after two years in sows, while males begin participating in the rut after 4–5 years, as they are not permitted to mate by the older males. The maximum lifespan in the wild is 10–14 years, though few specimens survive past 4–5 years. Boar in captivity have lived for 20 years.

Wild Boar rest in shelters, which contain insulating material like spruce branches and dry hay. These resting places are occupied by whole families (though males lie separately) and are often located in the vicinity of streams, in swamp forests and in tall grass or shrub thickets. Boar never defecate in their shelters and will cover themselves with soil and pine needles when irritated by insects.

The Wild Boar is a highly versatile omnivore, whose diversity in choice of food is comparable to that of humans. A 50 kg (110 lb) Boar needs around 4,000–4,500 calories of food per day, though this required amount increases during winter and pregnancy, with the majority of its diet consisting of food items dug from the ground, like underground plant material and burrowing animals. Boar may occasionally prey on small vertebrates like newborn Deer fawn, Leporids and Galliform chicks.

Piglets are vulnerable to attack from medium-sized felids like Eurasian Lynx, Jungle Cat and Snow Leopard as well as other carnivorans like Brown Bears and Yellow-Throated Martens. The Wolf is the main predator of Wild Boar throughout most of its range. A single wolf can kill around 50 to 80 Boar of differing ages in one year.