Sunflower seeds are a premier, nutritionally dense food source for a wide variety of wild birds. They are an excellent high-energy offering, providing fat and protein, which is vital during cold weather or nesting periods. Gardeners and feeder enthusiasts frequently rely on these seeds to attract diverse species to their outdoor spaces. Their popularity means sunflower seeds are often the most effective item to fill a feeder.
The Appeal of Sunflower Seeds
The desirability of sunflower seeds stems directly from their concentrated nutritional profile. These seeds contain high percentages of fat, protein, and fiber, delivering a fast and efficient source of energy. The fat content is beneficial, helping birds maintain body temperature and providing fuel for flight and daily activities.
Bird feeders typically offer two types of sunflower seeds. Black Oil Sunflower Seeds (BOSS) are preferred by the widest variety of birds due to their high oil content and thin hulls. The thin shell makes it easy for even small songbirds with weaker bills to crack open and access the kernel inside.
Striped Sunflower Seeds, in contrast, possess a thicker, harder shell. While they are a healthy food source, the robust casing requires a larger or stronger bill to open. Striped seeds are often chosen by larger species, while the thinner-shelled BOSS seeds are more universally accessible.
Identifying the Seed Eaters
The characteristics of the sunflower seed—primarily shell thickness—determine which birds will consume it. Small songbirds, which make up a large portion of feeder traffic, are highly attracted to Black Oil Sunflower Seeds. Species like chickadees, tufted titmice, and nuthatches easily handle the thinner shells, often taking a single seed to a nearby perch to hull and eat. Finches, including American Goldfinches and House Finches, also frequently visit, though Goldfinches often prefer shelled chips.
Medium-sized birds with robust, cone-shaped bills manage both striped and black oil seeds. The Northern Cardinal, a common visitor, uses its thick beak to crack even the hardest shells. Larger Blue Jays also readily consume sunflower seeds and often use platform or hopper feeders. Woodpeckers, such as the Downy and Hairy varieties, are drawn to the high-fat content and can be seen clinging to feeders to extract the seeds.
Ground-feeding birds, including Mourning Doves and sparrow species, consume seeds that have fallen below the feeder. Less desirable species, such as Common Grackles and squirrels, are also attracted to the seeds’ high energy content. Squirrels expend considerable effort to access any type of sunflower seed, making squirrel-resistant feeder design a common consideration.
Offering Sunflowers
The presentation of sunflower seeds influences the types of birds that visit and the amount of mess created. Shelled sunflower hearts or chips are popular because they eliminate the mess of discarded husks beneath the feeder. Since the kernel is exposed, birds expend less energy consuming the seed, making them suitable for species with softer bills, like robins and blackbirds.
Whole sunflower seeds, both black oil and striped, are typically offered in tube feeders or hopper feeders. Tube feeders, with their small perches and ports, are excellent for attracting smaller songbirds while limiting access for larger species. Platform or tray feeders provide an open surface that accommodates larger birds and can be used for both whole and shelled seeds.
A natural presentation involves leaving the dried heads of sunflowers in the garden during the fall and winter. Birds land directly on the spent flower head and harvest the seeds themselves. This method provides a seasonal food source and encourages natural foraging behavior.