Since their introduction into Britain in the 1870s grey squirrels have spread rapidly. They have displaced the red squirrel throughout most of England and Wales and in south-east and central Scotland.
Grey squirrels can cause serious problems for foresters, native wildlife and gamekeepers. The bark stripping from tree trunks during the months of May and June, damages stands of timber and natural woodland.
In spring, the taking of eggs and young chicks can be devastating for songbird and ground-nesting bird populations. Damage to hoppers, feed bins and water pipes can cause serious and costly shoot management problems.
The grey squirrel is also a significant factor in the decline of the native red squirrel population in the UK. Greys can carry the squirrel pox virus. And although they are relatively unaffected themselves, the disease causes considerable suffering and death to the red squirrel – which is already severely threatened and even extinct in many parts of the UK.
Grey squirrels have limited legal protection and can be controlled all year round by a variety of methods including shooting and trapping. It is an offence under section 14 of the Wildlife and Countryside Act (1981) to introduce and release grey squirrels into the wild. Under the provisions of the Animal Welfare Act 2006 any person responsible for a squirrel trap would only be responsible for any animal caught by it, not its offspring still in the wild. Under the act, it is an offence to cause unnecessary suffering to a kept animal (this includes live caught animals).
Methods of Control
At different times of the year the control of squirrels can take different forms. With the leaf off the trees, winter is a good time for shooting.
Drey poking can be effective, especially on cold winter days,. A team of four, with two working the poles and two covering the tree, can spend a day clearing a lot of dreys in a wood. When all the dreys are cleared from a wood in winter, it becomes easy to spot new ones made in the summer.
There are a few rules you must adhere to when carrying out this activity. Safety is paramount; Guns should stand well back from the tree. When using the poles, tap the bottom of the drey gently; this will allow the squirrel to run out slowly, it will probably stop just outside which will give the guns time to shoot. Never shoot at a squirrel running down a tree, it is better to either let it run down and run away from you or stop it and turn it back up the tree. Remember you are aiming to cull squirrels, so be efficient and effective.
This method is only one part of a fully effective control programme, as grey squirrels killed at this time of the year will often be replaced by others before the summer.
Tunnel trapping using spring traps
Spring traps are a very useful tool in catching squirrels. Set correctly, these traps will effectively catch squirrels moving between trees. Look for the signs of squirrel movement; a common sight is the flat circle around the base of the tree where squirrels run around sometimes chasing each other.
The law and best practice requires you to:
- Use the appropriate approved spring trap for your quarry.
- Enclose your trap within a natural or artificial tunnel
- Firmly anchor your trap
- Check your traps at least once a day
All traps should be set in accordance with BASC’s trapping pest mammals code of practice.
Live cage trapping
Live cage traps, either single or multi-catch, involve attracting squirrels to a trap with a bait (food). These can be used in the same way as spring traps. Set them at the base of trees and covered with logs. It is best to pre-bait these traps, leaving the entrances open so that the squirrels can run freely for a few days before setting.
The density of traps required depends on whether single or multi- capture traps are used.
Single traps should be spaced 75-125m apart, multi-traps 150-200m apart, equating to one trap per ha. In areas where it is difficult to draw squirrels to the ground – for example, pine mixtures, or where traps are disturbed by badgers, deer or wild boar – it may be necessary to site traps on platforms on the trees.
Captured squirrels should be humanely destroyed by guiding them to one end of the trap, where they can be killed with an air rifle, or the traps can be emptied into a sack and the squirrels dispatched through a swift, heavy blow to the head. Non-target species should be released immediately.
Shooting of grey squirrels can be a very effective method of control, especially in early spring when young shoots are showing in trees. On a sunny day grey squirrels will work in the outmost branches of a tree, chewing the new shoots and can present an easy target.
A shotgun or powerful air rifle would be suitable for this form of control but remember, as with all shooting, assess your background before taking any shot. If in doubt, don’t shoot. A rimfire rifle would be more suitable for shooting squirrels on the ground around the base of a tree where a safe backstop is provided.
The EU licence for the production and sale of warfarin as a grey squirrel bait ended on 30 September 2014. Manufacturers and stockists are no longer able to sell warfarin to control grey squirrels.
Disposal of carcasses
Unless you intend to eat them, all dead squirrels should be deeply buried or incinerated. Any carcasses showing signs of squirrel pox virus (scabs around eyes, nose, mouth and feet) should be sent to the Animal Health and Veterinary Laboratories Agency (AHVLA) for investigation. Gloves should be worn when handling potentially infected animals.