Black birds include various avian families with significantly different diets and behaviors. Predation on other birds, primarily in the form of nest raiding, is a highly opportunistic strategy for certain dark-plumaged omnivores. This difference in feeding ecology separates the true predators from the numerous insect and seed-eaters.
Identifying the Predatory Black Birds
The most recognized predatory black birds belong to the family Corvidae, which includes the American Crow and the Common Raven. These species are considered opportunistic omnivores, and other birds’ eggs and nestlings are a valuable source of protein, particularly during their own breeding season. Crows, for example, are known to be regular nest predators across many habitats, but the overall impact on prey populations is often smaller than commonly perceived.
Other dark-colored species that engage in this behavior include the Common Grackle and the European Starling. The Common Grackle, a member of the blackbird family (Icteridae), is known to consume the eggs and nestlings of other birds, and occasionally even attack small adult birds like House Sparrows. European Starlings, though often dark with iridescent plumage, are an introduced species in North America known for aggressively competing for nest cavities and sometimes expelling native occupants.
The Mechanisms of Avian Predation
The primary method is nest predation. This involves taking eggs and defenseless nestlings or fledglings from open-cup nests or cavities. This behavior is not typically an obligate feeding strategy but rather a high-reward, opportunistic supplement to a diet that already includes insects, fruits, grains, and carrion.
The young of other birds, being rich in fat and protein, are a concentrated food source highly sought after when the birds are feeding their own young. Adults of vulnerable species, such as those that are sickly or injured, are also occasionally targeted, though this is less common than raiding nests. Scavenging is another mechanism, where the birds consume carrion, which is a regular part of the Corvid diet.
Distinguishing Non-Predatory Black Birds
Many birds commonly referred to as “black birds” are non-predatory and focus on consuming plant matter and invertebrates. True blackbirds, such as the Red-winged Blackbird and the Brewer’s Blackbird, belong to the Icteridae family, which are primarily New World species. The diet of the Red-winged Blackbird, for instance, consists mainly of seeds from weeds and waste grain, with about a quarter of their intake being insects and other small animals, especially during the breeding season.
These species are categorized as insectivorous and granivorous, foraging on the ground in fields, marshes, and open habitats. Their slender, pointed bills are adapted for probing soil and manipulating seeds, contrasting with the much heavier, all-purpose bills of predatory corvids.