Red squirrels on the Isle of Wight are thriving and have sufficient food and natural habitats to support a growth in their population, a new study has found. Scientists also found that whilst the squirrels on the east and west of the island still have different genetic characteristics, there are signs that they are starting to mix.
Researchers from Bournemouth University teamed up with the Wight Squirrel Project to study squirrel movements, carry out genetic analysis of fur samples and map food availability and the natural environment on the island. They also carried out a public survey to learn about any supplementary feeding by residents.
Their encouraging findings have been published in the journal Biodiversity and Conservation.
“Island populations face a higher extinction risk than animals on the mainland because of their smaller population and vulnerability to environmental changes,” explained Alyson Buchanan, a PhD student at Bournemouth University and first author of the study. “Red squirrels on the Isle of Wight are the largest population in Southern England and genetically distinct from those across Europe, so it is really important to know how healthy they are to support their conservation,” she added.
Alyson and the team found that the island currently has enough trees and hedgerows for the estimated 3500 red squirrels that live there to thrive, and for their population to grow. They also concluded that there is enough availability of seeds, a key part of their natural food supply, to support them.
Previous research by the Bournemouth team found two distinct genetic make-ups between the squirrel populations on the east and west side of the island, possibly because ofroads and large open spaces in the centre.
The genetic analysis in this study went further by looking at more samples from squirrels found in the middle of the island. These findings found signs that the two populations are starting to cross breed.
“It is very good news that we found some movement between the two groups,” explained Dr Emilie Hardouin, Head of the School of Life and Environmental Sciences at Bournemouth University. “Bringing the two gene pools together would help the overall health of future generations of squirrel and help them to adapt to environmental changes. Whilst we still have the two different populations, it is very encouraging to have a gene flow between them,” she added.
Many residents on the Isle of Wight provide supplementary food for squirrels, either intentionally, or by leaving food out for birds. While this can help squirrels, the public survey carried out by the team suggests that more people could benefit from advice on what food to put out.
Helen Butler from the Wight Squirrel Project advised that “Feeding red squirrels in your garden in times of food shortage, such as the late spring and early summer, helps their survival. Unsalted peanuts in a wire feeder, meant for the birds, will initially attract squirrels to your garden. However, too many peanuts can cause thinning of the bone so please feed a variety of food. Fruit is good for them, although hazelnuts and walnuts are the all-time favourites. Never feed brazil nuts, like the peanuts they are far too oily.”
The team concluded that while more research can be done, unless there is a significant change to the current conditions and food availability, the Isle of Wight remains an ideal habitat for the charismatic rodents.
“As it stands, things look good for the island’s squirrels and we don’t think there is a high extinction risk for them,” Alyson concluded.
Alyson Buchanan’s PhD project is supported by BU, WightFibre and the Isle of Wight National Landscape.
