Blackberries are a widely cultivated and wild-growing aggregate fruit enjoyed by humans across the globe. These dark, juicy fruits signal the arrival of summer and early autumn, but they are not solely reserved for human consumption. Birds readily eat blackberries, establishing a common interaction that is often mutually beneficial in the wild.
Common Bird Species That Eat Blackberries
A wide variety of avian species are drawn to the ripe fruit, which provides a readily available source of carbohydrates and water. Common backyard birds frequently observed feeding on blackberry canes include the American Robin and various thrush species like the Hermit Thrush and Varied Thrush. These birds are particularly attracted to the soft texture and high moisture content of the fruit.
The European Starling is another prolific consumer, often descending in groups to feed on the berries. Cedar Waxwings, known for their love of fruit, also feast on blackberries, sometimes consuming them almost exclusively when available. Other feathered diners include the Northern Cardinal, Northern Flicker, and different species of warblers, all seeking this seasonal abundance.
Birds are attracted to the dark, ripe color of the fruit, which stands out clearly against the green foliage. Plucking and swallowing the fruit provides birds with necessary energy to support their active metabolisms. This seasonal feeding pattern highlights the deep integration of fruit-bearing plants into the local food web, where they serve as a temporary but important resource.
The Role of Birds in Blackberry Seed Dispersal
The consumption of blackberries by birds is an important ecological process known as endozoochory, or seed dispersal via animal ingestion. Blackberry seeds are small and hard, possessing a protective coat that allows them to pass through the avian digestive system mostly unharmed.
As the birds consume the fruit, the seeds travel through the digestive tract where they are subjected to stomach acids and enzymes. This exposure can help to scarify the tough outer seed coat, preparing the seed for germination once it is expelled. Seeds are deposited far from the parent plant in the bird’s droppings.
This process allows the blackberry plant to colonize new areas, reducing competition for resources with the parent cane. Migratory birds are especially effective dispersers, capable of transporting seeds over long distances as they move between habitats. The successful propagation of wild blackberries relies heavily on this symbiotic relationship with frugivorous birds.
Protecting Blackberry Crops from Wildlife
For gardeners and commercial growers, the birds’ natural feeding habits can result in significant crop loss, requiring proactive intervention to secure the harvest. The most effective method for protecting ripening blackberries is the use of exclusion netting, which acts as a physical barrier. Netting should be installed over a supportive frame or cage structure to prevent the mesh from resting directly on the canes, which can tangle birds and make harvesting difficult.
Visual deterrents provide a secondary line of defense by startling or confusing the birds, although these often require frequent changes to maintain effectiveness. Reflective Mylar tape or old CDs and DVDs can be hung near the canes to flash in the sunlight, creating unpredictable movement and light. Positioning a few large, reflective “scare-eye” balloons can also mimic the threat of a predator’s eyes.
A less common but sometimes successful approach involves taste aversion, where birds are repelled by an unpleasant flavor rather than a physical barrier. Some growers use products containing methyl anthranilate, a chemical compound found in grape flavoring that birds find highly distasteful. Applying these deterrents just as the fruit begins to ripen can signal to the birds that the crop is not worth the effort, encouraging them to forage elsewhere.