Hawks, which include soaring Buteo species like the Red-tailed Hawk and swift, woodland-dwelling Accipiters like the Cooper’s Hawk, are powerful birds of prey. These raptors typically occupy a high position in their food webs as opportunistic hunters of small mammals and birds. Despite their sharp talons and formidable beaks, they are not exempt from predation, especially during their most vulnerable life stages.
Predators Targeting Eggs and Nestlings
The most vulnerable stage in a hawk’s life cycle is when it is confined to the nest as an egg or a nestling. Predation on nests is widespread and often involves smaller, agile animals capable of climbing or flying stealthily. Raccoons are a major terrestrial threat, using their climbing ability to reach nests in trees, often succeeding by surprise under the cover of darkness. They consume both the eggs and the newly hatched young before the parents can effectively mount a defense.
Avian predators, particularly corvids like Common Ravens and American Crows, pose a significant threat. These intelligent birds may work in groups to distract adult hawks, allowing one individual to steal eggs or nestlings. Smaller owl species can also prey on eggs and young, though the larger Great Horned Owl is a more frequent and powerful nest raider.
Direct Predators of Juvenile and Adult Hawks
While fully grown hawks have few natural enemies, the most significant threat comes from other, larger raptors, particularly those that hunt at night. The Great Horned Owl is the most frequent predator of adult hawks in North America. These nocturnal hunters exploit the hawks’ diurnal activity pattern, ambushing them while they are roosting and less alert in their nighttime perches.
Larger eagles, such as the Bald Eagle and the Golden Eagle, also pose a threat to hawks through direct predation or aggressive conflict. These massive birds sometimes prey on smaller hawk species or juveniles, although they often prefer to target easier prey to avoid the risk of injury from a hawk’s talons. The conflict is not always strictly predatory; inter-raptor aggression and competitive exclusion, where larger raptors kill a smaller one to eliminate competition for territory or food, is a known occurrence. Furthermore, a form of cannibalism occurs when larger hawk species prey upon smaller ones.
Mammalian predators generally do not catch healthy, flying adult hawks, but they become a factor when the bird is grounded or vulnerable. Coyotes and foxes are known to prey on hawks that are hunting close to the ground, injured, or tending to a low-lying nest. Northern Harriers, which build their nests directly on the ground in marshes and fields, are especially susceptible to these mammalian predators.
Environmental Factors Increasing Vulnerability
A hawk’s susceptibility to predation is often increased by circumstances not directly related to a predator’s skill. Physical injury is a major factor, as a hawk suffering from a wing or leg fracture cannot fly or defend itself effectively. An injured hawk is easily picked off by any opportunistic predator it would normally deter, from coyotes to large owls.
Habitat degradation and fragmentation also force hawks into less optimal areas, which increases their exposure to danger. When natural nesting sites are lost, hawks may be compelled to nest in more accessible locations, making their eggs and young easier targets for ground-based predators like raccoons. Furthermore, illness and starvation can weaken a hawk’s ability to hunt, react, or defend its territory. A compromised immune system or a lack of energy reserves reduces the hawk’s overall fitness.