Exclusion Fencing
Trapping
Shooting
Supplementary Feeding
Poisoning
Immuno-contraception
Desperation
Free-living wild boar in the UK are currently not a protected species. Landowners and occupiers may kill them if they feel this is necessary, for example, to prevent damage to land or crops or to prevent the spread of disease. The method of control is at the discretion of individual landowners and occupiers, provided that the method used does not contravene current legislation, such as the Wildlife and Countryside Act 1981 and the Control of Pesticides Regulations 1986 (i.e. cruelty and poisoning are definately not allowed.)
If we do nothing, we will become over run with wild boar, and they will become urbanised. Some people may be in favour of this, some won't be.
In areas where wild boar have become urbanised, they lose their fear of people as they know they are less likely to get shot. They become accustomed to rummaging through bins for discarded food items, as seen in this
Polish video footage. Urban boar, similar to other wild animals that become urbanised, can lead to problems of aggression, road traffic accidents and disease spread.

An urban Berlin wild boar (this does beg the question though that maybe the domestic cats in Berlin need controlling more than the boar? (copyright unknown)

Another urban Berlin wild boar, this time scavenging through a dustbin - its not nice to see a wild animal behaving like this. (copyright unknown)

... there's something not right about seeing this Polish wild boar eating chips.
So, the million dollar question is - How do you keep wild boar out of areas where they are not wanted?
There are several methods that are used, and they are listed below. The degree of effectiveness depends on the amount of time, effort and money put in. A look across to the european continent shows that wild boar numbers are increasing considerably, despite being hunted virtually everywhere they occur - a testament to their survival abilities.

An outdoor pig unit in Sussex. How does the owner keep an amorous free-living male wild boar away from his domestic sows? - because that single strand electric wire certainly won't.
Similarly, how does the owner of this field in Gloucestershire stop the wild boar from ruining the only pasture available for the horses? (reproduced with permission)
We attempt, below, to shed some light:
Exclusion Fencing
Fencing has been used successfully to exclude wild boar from areas where their presence was not desired - but fencing is expensive. The height of the fence is important because if alarmed, a wild boar can clear a five foot fence with ease.

Fencing in East Sussex dug down to prevent rooting. Note that this fence is not high enough, the boar jump over it!
Fence designs are varied, but the bottom line is for it to be sturdy and dug into the ground by about 12 inches to prevent the boar from rooting underneath. Typical stock fencing, the type used to keep out rabbits for example, is not suitable.
Maintenance is essential as a fence is only as strong as its weakest link and constant monitoring is required to guard against, for example, breaches by a fallen tree or, for an electric fence, to prevent grass and undergrowth from shorting out the current. Wild boar can root under fencing if the ground is sufficiently soft, although this can be prevented to some extent by burying the lower part of the fence into the ground or incorporating a snout wire (a length of barbed wire running along the ground at the foot of the fence). Adding a couple strands of electric wire just in front of the fence, although not essential, further increases its effectiveness.
In this Suffolk wild boar farm enclosure, the effectiveness of the two strands of electric wire is very noticeable.
Trapping
Wild boar will enter baited traps and this method has been employed in boar control operations throughout the world. Trapping success can be improved by trapping at a time of year when the animals are naturally more hungry. Juvenile wild boar are easy to trap, the more mature animals are wiser and much more difficult. However, certain individuals are also trap-shy and won't enter a trap for love-nor-money.
Using multi-capture traps, as opposed to single capture, is more likely to trap mature animals. The juveniles entering first do not trip the trap as with single-capture traps allowing mature animals to enter later, when they believe there is no mischief going on.
A trap design that proved effective in capturing wild boar in East Sussex.
Trapping efficiency is not thought to improve by the use of the appropriately named "Delilah traps" in which sows in oestrus were placed in the traps as bait to encourage male animals.
Trapping is can be time-consuming and there is the problem of transporting the traps into the most effective areas. Plus there is the question of what to do with none target species entering, or springing the trap, before the boar enter. In Britain this is typically badgers.
Other points to consider when trapping wild boar:
For animal welfare reasons traps need checking daily.
Think where you should place the traps for maximum trapping efficiency.
Decide how far apart each trap should be.
Getting traps into position can be difficult and sometimes dangerous .
Know what do you do with a wild boar once it is in the trap.
Some wild boar are 'trap shy' and will never enter traps. Conversely, some are 'trap happy' and will continually be caught (unless shot of course!)
Remember members of the public often do not understand/appreciate trapping endeavours so place traps away from public footpaths.
Do not trap in the breeding season when females may have dependant young.
Remember your own health and safety: wild boar bite and slash. When in a trap, they (not surprisingly!) are very angry and dangerous.
Know what to do when non-target species are trapped.
If trapping to remove boar from an area remeber the rule about having more traps than there are wild boar because ‘trap numbers should not be limiting’
Shooting
Shooting has in certain circumstances proved an effective method of boar control. Problems encountered with shooting as a form of control include animals dispersing at the sound of the shot, the difficulty of shooting in wooded, wet or marshy terrain, and the inherent danger of using high-powered large-calibre weapons (particularly in poor light conditions) and concerns over animal welfare issues.
In the UK, most boar have been shot from high seats or at artificial bait stations. Boar will readily come to bait stations and can be shot like bluetits on a bag of nuts. As opposed to a 'sport', shooting at bait stations is purely a way to keep boar numbers down and to stock up the freezer.
Farmers typically see foxes around dung heaps, but wild boar on this heap in Gloucestershire is certainly different! (reproduced with permission)
The Department for the Environment, Food and rural Affairs (DEFRA) state that Police Firearms Licensing Branches require that wild boar are specifically listed on an individual's firearms certificate (FAC) before they may use a rifle to shoot wild boar. They do not consider the term "other vermin", which often appears on FACs to permit the culling of species such as foxes, to include wild boar. The most suitable type of firearm for shooting wild boar is a centre-fire rifle comparable with those permitted for deer culling under the Deer Act 1991. However, the minimum calibre permitted for deer is widely considered to be inadequate to ensure a clean kill for wild boar. Police guidance suggests a minimum calibre of .270 Winchester, or its metric equivalent (see Home Office; Firearms Law: Guidance to the Police, 2002) and a FAC will normally only be endorsed for shooting of wild boar if the rifle held is of .270 calibre or larger. Wild boar will normally only be added to a FAC if the holder has authority to shoot on land within an area known to have wild boar present.
In France for example, shooting in combination with tracker dogs has proved to be an effective way of removing residual boar that survive other forms of control, but in the UK hunting with dogs is banned so this is not an option. Without dogs to flush out a boar, shooting in the UK is likely to be a 'sport' or 'control method', as opposed to an eradication method.
"Hi, I have attached a photo of some boar my son in law shot in December 04 [in Kent]. I have just heard that a large one has been shot near Tonbridge in an area which has a lovely bit of woodland, despite a duel carriageway now running through it.
Hope this is of help. Malcom." (reproduced with permission)
Supplementary Feeding
To reduce agricultural damage by keeping wild boar in forested areas, supplementary feeding at a time when the crops are most likely to be damaged has been effectively implemented in regions of Poland for example. In Russia also, the planting of foraging fields within the forest, containing maize, oats or potatoes, has also deterred wild boar from raiding farmland. These sacrificial crops require fencing which is only opened during times when agricultural damage is likely.
On the other hand, supplementary feeding can increase wild boar population size as the additional food improves the condition of the animals, with a subsequent increase in potential for agricultural damage.
The overall benefit of supplementary feeding is still up for debate.
Poisoning
Successful reductions in feral pig numbers have been achieved by poisoning, particularly in areas of Australia. Poisoning is particularly suitable to the extensive Australian agricultural systems as it is low in cost and can be implemented over a large area. Sodium monofluoroacetate A1080 is commonly used and is considered to be the most effective poison. However, a problem with 1080 is that a poisoned feral pig will vomit repeatedly prior to death and the vomit contains enough poison to kill any non-target species that ingests it. In addition, widespread distribution of non-specific poisons is in itself a direct threat to non-target species.
Warfarin has also been used.
Poisoning of a large and magnificent wild animal like the wild boar is rather barbaric and in the UK totally illegal.
Immuno-contraception
Immuno-contraception (fertility control) has the potential to be used as an alternative to lethal methods for limiting population growth in overabundant species. The most promising fertility control agents are immunocontraceptive vaccines which stimulate the immune system to produce antibodies that neutralise proteins essential for reproduction. Among these agents, the newly developed Gonadotropin Releasing Hormone (GnRH) vaccine suppresses the activity of GnRH which, in turn, interrupts the hormonal processes leading to ovulation and sperm production. Through the addition of novel adjuvants to boost the immune response, single-dose GnRH vaccines have been demonstrated to induce infertility experimentally in a variety of mammal species. Such “single-shot” vaccines represent a major technological breakthrough that makes some practical applications realistic. However, the potential side effects of these vaccines on animal behaviour, physiology and welfare remain poorly understood.
For further information on wild boar and immuno-contraception visit the Defra and Wild Boar page.
Desperation
After his crops were damaged by wild boars for years, a Japanese farmer has fought back and created a "family of scarecrows," including a baby in a stroller and a child on a tricycle.
The scarecrows have proven a popular site in the area and damage to his crops has been greatly reduced.
" (reproduced with permission)