Tree swallow

The Tree swallow (Tachycineta bicolor, synonym Iridoprocne bicolor) is a member of the swallow family (Hirundinidae) that can occasionally act as an agricultural pest. While primarily insectivorous, these birds can cause significant damage to commercial fruit and berry crops when their natural food supply dwindles or when migrating flocks congregate near orchards.

The main crops susceptible to damage include blueberries, grapes, and strawberries. Tree swallows are opportunistic feeders, and in periods of fruit ripening, they consume ripe berries, which directly affects the economic yield and marketability of the produce. Their presence is particularly detrimental to high-value fruit production systems.

The life cycle involves seasonal nesting followed by the formation of large, communal flocks in late summer. This migration cycle often overlaps with the peak harvesting season of various berries. During this period, flocks are highly mobile and can inflict substantial damage in a short timeframe, necessitating proactive management strategies by growers.

The nature of the damage involves the pecking of berries, which creates entry points for moisture, insects, and fungal pathogens. Once the skin of the fruit is broken, secondary rots and infections spread rapidly throughout the crop, often leading to a significant increase in waste during harvest and reduction in storage shelf life.

Effective management requires a combination of physical and deterrent methods to protect the crops.

• Installation of exclusion netting is the most reliable method
• Use of bioacoustic deterrents that mimic predator calls
• Deployment of visual scare devices, such as reflective tape or predatory bird decoys