Owls are nocturnal birds of prey known for their silent flight and specialized senses. These raptors are efficient predators of various small animals and occupy a position near the top of the food web. Their predatory behavior sometimes extends to consuming other owls. This consumption can involve preying on a different, smaller species or engaging in true cannibalism within the same species.
Intraspecies Predation Among Owls
The straightforward answer is that owls do eat other owls, though it is not a primary food source. This behavior is categorized as either intraspecies predation (one owl species preying on another) or true cannibalism (consuming a member of the same species). Documented examples of owl-on-owl predation typically involve a larger, more powerful species overpowering a smaller one.
The Great Horned Owl (Bubo virginianus) is a significant predator of other raptors in North America. This large owl frequently preys on smaller species, including Screech Owls, Barn Owls, and the closely related Barred Owl. In some areas, Barn Owls can make up a noticeable percentage of the Great Horned Owl’s diet, demonstrating an established, opportunistic feeding pattern.
True cannibalism, consuming a member of the same species, is observed, particularly among nestlings of species like the Barn Owl and Short-eared Owl. In these cases, older or stronger chicks may kill and consume their smaller, weaker siblings, a behavior known as siblicide. This adaptation ensures the survival of the fittest nestlings when food resources are extremely limited.
Factors Driving Cannibalistic Behavior
The primary forces driving an owl to consume another owl are environmental necessity, territorial disputes, and opportunistic feeding. Intraspecies predation often results from size dimorphism, where the difference in size makes a smaller owl an easier target than other available prey. For example, a small owl may be viewed as a meal source by a much larger owl, such as the Eurasian Eagle Owl preying on smaller Long-eared or Little Owls.
Extreme resource scarcity is the most significant driver of true cannibalistic acts, especially within a nest. If parents cannot supply enough food, the largest chicks gain a competitive advantage. They may eliminate smaller siblings to reduce competition and sometimes consume their remains for nutrition. This mechanism helps ensure that the parents can successfully fledge some healthy offspring rather than losing the entire brood to starvation.
Territorial aggression is another factor, particularly among large owl species vying for prime hunting and nesting areas. A fatal attack on a competing owl can eliminate a rival and secure exclusive access to resources. The body then becomes an available food source. While consumption is often secondary to eliminating a competitor, it is a logical outcome for an efficient predator.
General Owl Diet and Hunting Strategies
The consumption of other owls is an exception to the routine diet of most species, which are generalist carnivores. The typical owl diet is diverse, consisting mainly of small mammals like voles, mice, and shrews. Depending on the species and habitat, their prey also includes insects, fish, reptiles, amphibians, and other birds.
Owls possess specialized adaptations that make them highly effective hunters. Their flight is virtually silent due to serrated edges on their wing feathers, which muffles the sound of air passing over the wings. This acoustic stealth allows them to approach prey without warning, a technique employed by species like the Barn Owl.
Hunting techniques vary, but often involve the “perch and pounce” method, where they wait on a low branch or post before swooping down onto their target. Others, like the Short-eared Owl, utilize a quartering flight, scanning the ground while flying low over open areas. Combined with their exceptional hearing and keen eyesight, these adaptations allow owls to locate and dispatch prey efficiently.