Hazelnuts are a natural whole food and chosen by a variety of wildlife species as part of their diet. They are loved by both Red and Grey Squirrels and they contain nearly all the nutrition they need, whereas feeding too many peanuts can leave them with calcium and vitamin deficiencies. Hazelnuts are also eaten by various species of mice, voles, Dormouse, Nuthatches and Woodpeckers. You can tell who has visited the garden by the way they eat a hazelnut, Squirrels tend to split the shell in two where are voles, mice and dormouse gnaw a hole. Depending on the gnaw marks you can even make an accurate guess as to which animal had a chew. Nuthatches and woodpecks sometimes wedge the nuts into a hole so they can have a good change of breaking the shell.

Additionally, being rodents, squirrel, mice and vole teeth continue to grow, and gnawing is an essential activity to keep there teeth at the right size.