Wild rabbits are responsible for huge losses, currently estimated in excess of £100m annually, to a wide range of agricultural and horticultural crops, amenity turf such as golf courses and young trees.
Unless you live in the city of London, Isles of Scilly or on Skokholm Island off Pembrokeshire, you are legally responsible for destroying wild rabbits on your land or taking steps to prevent them from causing damage.
But such is their natural tendency to reproduce and the cost required to control them, Defra suggests that landowners should aim to reduce numbers to a point where the damage caused is economically acceptable because complete eradication is "impractical".
The viral disease myxomatosis is believed to have wiped out 99 per cent of the rabbit population within a couple of years in the 1950s. Rabbits have since developed some immunity to the disease, which explains why populations are now believed to be increasing by two per cent annually.
A newer disease, viral haemorrhagic disease, is not expected to lead to such a reduction in numbers. Defra recommends that neighbours take cooperative action in rabbit control but if you continue to suffer serious crop damage from rabbits sheltering on adjoining land, the department has the authority to investigate the complaint.
There are various forms of protection and control methods depending on the extent of the problem and the time and money available, but gassing is said to be the most effective. Causing unnecessary suffering, however, is an offence under the Wild Mammals (Protection) Act 1996.
Control is recommended to be carried out between November and February, or March in the North, when populations are at their lowest. Guidance can be found in Natural England's Technical Information Note TIN003 and the Forestry Commission's Practical Notes.
During the day, rabbits shelter in communities in a warren, a network of underground tunnels, coming out to feed at night or early morning/late evening as well in summer. How deep the warren goes depends on soil type and water table. Rabbits can mate from just four months old. Females can produce a litter of up to six offspring every month during the breeding season, which spans January to August.
Rabbits will eat seedlings and graze or browse on young trees. Some leafy plants can be eaten to ground level. Feeding on young shoots leaves a characteristic sharply-angled cut. On older trees, bark can be stripped off up to half a metre from the ground.
Treatment: biological control
Grazers (a calcium chloride solution) is an anti-feeding product that can be applied year-round but is most effective when young growth is present on actively growing crops. It is rainfast in one hour and contains a wetting agent. In dry conditions, it can last up to six weeks. Repeat applications are required when overhead irrigation is used.
Treatment: cultural control
Fencing - The recommended specification for wire netting is a minimum height of 0.75m with British Standard 31mm 18-gauge hexagonal mesh. The base should overlap with the ground and be buried facing away from the enclosure, to a width of 15cm. Where there has been high pest pressure or rabbits have been climbing fences, allow for a "turnout" - an angled overhang at the fence top. In areas of badger activity, special gates need to be installed. Netting or trained-wire electric fencing is also an option, particularly for temporary situations. Inspect and repair regularly.
Ferreting - This involves setting ferrets down burrows to drive rabbits into nets, which can be time-consuming and ineffective unless used alongside other methods.
Shooting - Best used alongside other methods and is subject to legislative requirements.
Trapping - Various methods can be used but all need to be checked at least once a day (twice in the case of baited cages) and the caught rabbits humanely killed. Drop box traps are for use with wire-mesh netting.
Tree guards: 60cm high mesh guards or shelters are recommended for newly-planted shrubs and trees.
Treatment: chemical control
Active ingredient: Aluminium phosphide
IRAC code: 24A
Formulation: Various including Phostoxin (Rentokil)
Action(s): Fumigant pellets approved for use against rabbits in farm woodland, grassland, lawns, managed amenity turf and farmland depending on product. In contact with moisture, compound releases toxic phosphine gas. Pellets are placed at each entrance to burrow or run, sealed in but uncovered by soil. Only to be used by operators trained in the use of aluminium phosphide. Cannot be used in wet weather. Rabbits must be driven to ground before gassing. Bodies must be dug out and safely disposed. Care must be taken not to treat burrows close to badger or fox settlements or where any animal or bird protected by the Wildlife & Countryside Act 1981 may be using the burrows. Applications of these products have been subject to recent legislation changes - see www.ramps-uk.org. The Register of Accredited Metallic Phosphide Schemes aims to maintain best practice and the sustainable use of metallic phosphide products through training and registering of stockists and operators. There is a range of products available for the retail sector containing aluminium ammonium sulphate, which acts as an animal repellent. Restrictions apply.
Fully updated by Dove Associates.
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