Eurasian red squirrel

Systematic position: The Eurasian red squirrel (Sciurus vulgaris) belongs to the order Rodentia, family Sciuridae. While typically a forest dweller, it can act as a significant agricultural pest when it invades orchards, vineyards, and nurseries in search of high-energy food sources, especially during periods of food scarcity in its natural habitat.

Crops affected: The species primarily damages nut-bearing trees such as walnuts and hazelnuts, but also targets pomaceous and stone fruits like apples, pears, and plums. Furthermore, in nurseries, they can cause significant damage to young shoots, buds, and delicate bark, which hampers the growth and structural development of young trees.

Biology and development: These rodents are diurnal, showing peak activity in the early morning and late afternoon. They reproduce twice per year, building complex nests called dreys high in tree canopies. Their exceptional agility and climbing speed allow them to effectively forage across extensive orchard areas, making them difficult to monitor constantly.

Damage character and economic impact: The primary economic damage is the destruction or spoilage of harvest. By gnawing into fruits and nuts before they reach maturity, squirrels create entry points for pathogens, leading to fruit rot and premature fruit drop. Additionally, bark stripping on young branches can lead to branch dieback and reduce the overall yield potential of the trees.

• Installing smooth metal baffles around tree trunks to prevent climbing.
• Using ultrasonic repellent devices to deter squirrels.
• Applying protective netting to individual valuable tree crowns.
• Clearing fallen fruits and nuts from the orchard floor promptly.
• Utilizing scent-based commercial repellents on foliage.

Protection measures: Management of red squirrels focuses on exclusion and non-lethal deterrence. Physical barriers, such as slippery metal collars placed around trunks, are highly effective in preventing squirrels from reaching the canopy. Furthermore, managing the orchard environment by removing debris and utilizing acoustic or visual deterrents helps maintain the trees in good condition without significantly disrupting local biodiversity.