Warning issued to Homes with Grey Squirrels in December
Grey squirrels can cause significant problems year-round, including during the coldest winter days.
They are often a charming sight in gardens—quick, agile visitors that many people enjoy watching as they hop about. But they are not native to Britain. Grey squirrels are an introduced species that have outcompeted the native red squirrel and can cause damage to gardens, pose risks to birds, and even affect your home.
If left unchecked, grey squirrels may invade roof spaces, gnaw timber, and damage plumbing and electrical wiring. They can be particularly troublesome for garden birds, sometimes scavenging feeders and posing a threat to nests.
A report summarized by British Red Squirrel.org, drawing on a Forestry Commission survey of vulnerable woodlands in Great Britain, found widespread damage attributed to grey squirrels: 100% of sycamore, 66% of beech, and 30% of oak and sweet chestnut trees showed signs of damage. In addition, these invasive mammals prey on wild bird eggs and chicks in gardens and steal food from feeders.
In winter, when food becomes scarce, birds rely on available resources, but grey squirrels may disrupt this balance by taking food from feeders and tables. They can also target eggs as spring arrives.
British Red Squirrel advocates note that grey squirrels eat songbird chicks and eggs. Research conducted by the Game Conservancy and Wildlife Trust suggests that grey squirrels can negatively affect native woodland birds, reducing fledging rates by about 15%. They also threaten crops, ornamentally valued trees, and stored bulbs, and they may enter roof spaces, causing damage to thatched or shingled roofs, as well as wires and cables.
The presence of grey squirrels has contributed to the decline of the native red squirrel in many areas, as the grey squirrel competes for food and habitat and can carry a lethal squirrelpox virus that does not affect it but is deadly to red squirrels.
If you’re looking to deter squirrels, one suggested method is sprinkling chili powder in the garden. However, this approach does not distinguish between the native red squirrel and the invasive grey variety, so it may affect both species.
BritishRedSquirrel.org recommends residents verify whether their area is home to red squirrels or a reintroduction program. They advise contacting local conservation groups or checking their red-squirrel map to determine the best course of action. If your area hosts only grey squirrels, look for nearby grey-control projects and consider organizing a community grey-control group.
Grey squirrels can also impact homes, not just gardens and wildlife. If you find them on your property, it’s prudent to consult Environmental Health for guidance.
In particular, grey squirrels often have litters around February, which can make them especially troublesome in late winter and early spring. If they access your roof space, they may damage roof timbers, plumbing, and wiring through gnawing.
If you currently have grey squirrels nesting in your roof, contact Environmental Health for assistance. To prevent further infestations, repair roof damage such as eaves and soffits, install durable wire mesh, and prune back overhanging branches to reduce access to your home.
