The sight of a bird preying on another, especially a vulnerable nestling, can be unsettling for many observers. European starlings, common in many landscapes, sometimes draw concern regarding their dietary habits, leading to questions about whether they consume baby birds. Understanding their diet and behavior provides clarity on this question.
The Truth About Starling Diet
European starlings are omnivorous, meaning their diet includes both plant and animal matter. Their primary food sources are invertebrates like beetles, grasshoppers, caterpillars, spiders, snails, and earthworms. They frequently forage in open, grassy areas, probing the ground with their stout, yellow bills to find grubs and other insects.
Beyond insects, starlings consume numerous plant-based foods, including fruits like cherries, mulberries, and other berries, along with seeds and grains. They are adaptable foragers, often found near human habitation, where they may consume human food scraps. While their diet is diverse, consuming nestlings is not a primary or consistent part of their feeding strategy.
Why and When Starlings Prey on Young Birds
While not a staple, starlings can opportunistically prey on the eggs and young of other bird species. This behavior is often driven by a need for protein, particularly during their breeding season, which typically runs from March to July. During this period, both adult starlings and their chicks require a high-protein diet for growth and energy.
Starlings are cavity nesters, using holes in trees, buildings, or nest boxes. Their aggressive nature can lead to competition for these nesting sites with native birds. In some instances, male starlings may remove the eggs or young of other species from a nest to claim the cavity for themselves, a behavior observed with bluebirds and woodpeckers. This aggressive displacement primarily secures breeding territory, rather than serving solely as a food source.
Starlings and Ecosystem Dynamics
The European starling’s presence in North America and other parts of the world stems from its introduction in the late 19th century. Their population has expanded significantly, with estimates over 150 million in North America. This widespread distribution is due to their adaptability to various habitats, including agricultural lands, urban areas, and suburbs.
As an introduced species, starlings compete with native birds for resources, particularly for limited nesting cavities. They aggressively displace native cavity-nesting birds such as Eastern Bluebirds, Purple Martins, and woodpeckers. While their impact on native bird populations is studied, some research suggests their overall effect on the decline of many native species may not be as extensive as sometimes perceived.