The Common Grackle (Quiscalus quiscula) is a widely recognized bird across North America, known for its iridescent plumage and distinctive calls. These birds are highly adaptable, thriving in various environments from urban parks to agricultural fields. Their varied and flexible diet is a primary reason for their widespread presence and success, allowing them to adjust to different habitats and seasonal food availability.
Main Dietary Components
Common Grackles primarily consume insects and plant matter. Insects are a significant food source, especially during the breeding season. They forage for a variety of insects, including beetles, grasshoppers, caterpillars, grubs, spiders, millipedes, and earthworms.
Plant matter is a substantial portion of their diet, particularly in colder months. They eat various seeds, including sunflower seeds, acorns, and sweetgum. Grains like corn and oats are also important, with grackles feeding on ripening corn and corn sprouts. Fruits and berries further supplement their diet.
An Opportunistic Eater
Beyond their primary diet, Common Grackles exhibit opportunistic feeding behaviors. They consume small vertebrates such as frogs, lizards, small fish, and mice. Their diet can also include crayfish and salamanders. Grackles have been observed raiding nests to eat the eggs and nestlings of other birds, and may also attack and consume adult birds, including House Sparrows.
Common Grackles also utilize human-provided food sources. They frequently visit bird feeders, consuming various seeds and grains. They also eat discarded food scraps and garbage, readily picking through bins for edible items.
How and When Grackles Eat
Common Grackles use various foraging behaviors to obtain food. They commonly walk on the ground in lawns and fields, using their long bills to pick up insects and seeds. They may also probe the ground or flip over leaves and debris to uncover hidden invertebrates. Grackles catch insects in flight, and wade into shallow water to catch aquatic prey like small fish and crayfish.
Their diet shifts seasonally. During the spring and summer breeding season, their diet consists primarily of insects and other animal matter, essential for feeding their young. In fall and winter, grackles rely more heavily on seeds, grains, and agricultural crops, which are more readily available. They often forage in large communal flocks, especially outside of the breeding season.