What additional action can be taken to benefit red squirrel conservation?
Having examined the causes of decline in the red squirrel population, this section looks at additional action that can be taken to benefit red squirrel conservation.
Management of the area surrounding a "Preferred Area"
The surrounding land can influence the viability of a red squirrel population, by either encouraging or discouraging its main competitor, the grey squirrel into the"Preferred area". The occasional felling of a narrow belt of mature broadleaves may be justified where grey squirrel incursions are known to occur. These trees can be replaced with other broadleaves or mixed woodland which are more beneficial to red squirrel conservation.
Grey squirrel incursions into a red squirrel habitat are encouraged by -
- low lying areas surrounding a favoured area or by connecting woodland, or
- hedgerows from the outlying area into the red squirrel conservation area, or
- along river corridors which the grey squirrels are known to travel
Grey squirrel incursions are minimised, if the red squirrel conservation area is-
- bounded by mountains, or
- large rivers or the sea, or
- major roads or
- open ground surrounded by tree species which are not attractive to the grey squirrel
Controlling the grey squirrel population
Eradication of the grey squirrel is neither a practical option nor a desirable one. It will be necessary however, to control populations in buffer zones and core areas- at levels below 1 resident adult/ha of woodlands in the buffer zone, and below this in the core area. It may also be necessary to control grey squirrels outside the "preferred areas, if populations reach a level where tree damage is imminent. Grey squirrels can cause extensive damage to broadleaves through bark stripping from the trunk and the main branches of the tree, between May and July. Damage by the grey squirrel often tends to be more severe than that caused by the red squirrel. This may be attributed to the higher densities that grey squirrels can attain in broadleaved woodland.
Good practice in grey squirrel control
Cage trapping is a more effective method of control than shooting. The use of wheat rather than maize tends to avoid the unwanted capture of red squirrels. The cages should be checked twice a day, 2-3 hours after dawn and again just before dark. They should be placed above ground level to avoid trapping of non target species. The optimum period for control is prior to the young squirrels developing into young adults- from February-end of July. Traps should be cleaned after a successful catch.
Warfarin is not permitted as a means of grey squirrel control in Northern Ireland.
Supplementary feeding
In certain situations supplementary feeding may benefit red squirrels, particularly in times of real food shortage during the winter months. Open feeding on tables should not be encouraged in areas frequented by both red and grey squirrels. Instead only tree mounted food hoppers which allow access to the red squirrel but restrict entry to the grey squirrel should be used. Locally constructed red squirrel feeders are currently in use at Tollymore Forest Park and results to date have been encouraging. The following guidance on diet requirements and location and maintenance of feeders should be followed to maintain a healthy population of red squirrels.
Food
In the wild, red squirrel diet consists principally of tree seeds, fruits, berries and fungi and they are also known to eat buds, shoots, flowers, bark, invertebrates and lichen. Some squirrels are known to chew bones, which may indicate that even this varied diet is deficient in calcium.
- Recommended foods for supplementary feeding include peanuts, sunflower seeds, hazelnuts, pine nuts, walnuts, beech nuts, carrots and apples. (Of these, only carrots contain sufficient calcium to prevent calcium deficiency).
- It is therefore advisable to provide an additional source of calcium such as previously boiled bones, antlers or cuttlefish at feeding sites.
It is important when feeding red squirrels in their natural environment to ensure that they receive a varied and balanced diet. Metabolic bone disease has been diagnosed in wild red squirrels in Britain and there maybe an association with supplementary feeding. Affected squirrels may show lethargy, loss of weight and a hunched posture due to curvature of the spine.
Location of Feeders
Red-only feeders should be used where both red and grey squirrels are present and should be situated in areas easily accessible for maintenance.
Feeders should be set in woodland between 2-3 metres from the ground, against the stem of a reasonably large tree. The tree should connect with the canopy of other trees to encourage access by squirrels. Feeders should not be placed at a height where ladders are required for routine maintenance. They should be located in quiet areas of woodland where the chance of accidental discovery is low.
- Feeders should be held in position by the use of straps, copper nails or wooden pegs (ordinary nails must not be used).
- It may take some time for squirrels to find a feeder and associate it with food. Some food should be scattered around the feeder at this time.
Maintenance of Feeders
Supplementary feeding of red squirrels in their natural environment poses a potential risk of disease, which is however, likely to be little more than they would encounter naturally.
Fresh food should be added regularly and stale food removed to reduce the risk of disease transmission. This will depend on the amount of use the feeder receives but should be at least weekly.
Squirrels are encouraged to spend more time at specific areas in their normal range than would normally be the case. Other rodents and birds can be attracted by spilt food from hoppers, resulting in a localised increase in their numbers, thus increasing the risk of disease transmission.
Sticky tape can be used in the roof of the feeder tunnel to help determine what is using the feeder, as rats, mice and young grey squirrels can all gain access under certain conditions. Access by small birds can be controlled by hanging plastic strips over the entrance to the tunnel.
Squirrels are susceptible to a number of bacterial and viral diseases, which can be transmitted in a variety of ways including fleas, lice and skin contact.
Food hoppers are a potential source of disease because they become soiled with excreta and can become contaminated by hairs. In addition, crevices and cracks can provide a retreat for fleas, lice and ticks.
- Although the correct use of disinfectants in cleaning food hoppers is important, thorough washing and removal of organic matter from all surfaces is even more so. Disinfectants are less efficient in the presence of organic matter, increasing the likelihood that some organisms will survive. Any multi-purpose disinfectant is suitable and extra strong solutions are unlikely to be more efficient.
- All disinfectants should be used in accordance with the manufacturers’ instructions.
- Feed hoppers should be cleaned regularly, possibly once or twice a month, according to the degree of soiling.
- Hoppers that are damp inside should be thoroughly dried before re-use and it may be desirable to have spare clean hoppers as replacements.
- Contamination of the immediate environment, such as tree trunks and branches, should be noted. To reduce contamination of the local environment it is advisable to move feed hoppers periodically to different trees.
- Some infections of squirrels are potential pathogens of humans. It is advisable to wear protective rubber or plastic gloves when handling contaminated feed hoppers.
Although there is some concern that supplementary feed hoppers can facilitate the transmission of poxvirus between squirrels, there is currently no evidence to suggest that the virus has been transmitted to the red squirrel population in Northern Ireland.
Purchase of Feeders
However, to reduce the risk of disease, emphasis should be placed on the regular maintenance of the feeders.
Red squirrel feeders suitable for areas where greys and reds co-exist are available from
Alpe Thermo Products
Tel: 01509 620217
Email: alpethermo@aol.com
Web address: www.thermoproducts.co.uk
Costs approx: £75.00 with postage