A hawk is a bird of prey, or raptor, characterized by exceptional eyesight, a sharp hooked beak, and powerful talons designed for catching and killing live animals. Hawks belong to the family Accipitridae, which also includes eagles and kites, and their existence is defined by predation. While they are top-tier hunters, the behavior of a hawk preying upon another hawk is not a typical hunting strategy. It does occur, however, under specific, often extreme, circumstances.
What Hawks Typically Hunt
The daily diet of a hawk is largely determined by its species and specialized hunting style, generally involving prey easier to subdue than another raptor. Hawks are broadly categorized into two main types: soaring hawks (Buteos) and bird hawks (Accipiters). Buteo species, such as the Red-tailed Hawk, have broad wings and primarily target small mammals like mice, rabbits, and squirrels, often spotting them from high perches.
Accipiters, including the Sharp-shinned and Cooper’s Hawks, possess shorter, rounded wings and long tails that allow for maneuverability within dense forest canopies. These specialists mainly hunt other birds, relying on speed and surprise to capture species like sparrows and warblers mid-flight. Most hawks are opportunistic, and their menu also includes reptiles, amphibians, and large insects. Raptors typically focus on prey averaging between 12% and 50% of their own body weight, selecting for efficiency and minimizing injury risk.
Intraspecific Predation and Cannibalism
When a hawk eats another hawk of the same species, the behavior is termed cannibalism, which most often involves nestlings rather than actively hunted adults. Cannibalism among raptors is well-documented and occurs in five distinct forms: siblicide, filicide, non-parental infanticide, conspecific strife, and conspecific scavenging. Siblicide, where a stronger nestling kills a weaker sibling to reduce competition for food, is common when resources are scarce.
Filicide (a parent killing its own nestling) and non-parental infanticide (a hawk attacking and eating young from a nearby nest) are also observed, particularly in species like the Red-tailed Hawk. These actions serve the evolutionary purpose of brood reduction, ensuring the survival of the strongest offspring. True adult-on-adult cannibalism is exceedingly rare and usually categorized as conspecific strife, where a territorial battle ends in death and the victor consumes the fallen competitor. More frequently, an adult hawk engages in conspecific scavenging, feeding on the carcass of an already dead hawk of its own kind.
Larger Hawks Preying on Smaller Raptors
Predation between different raptor species is slightly more common than same-species cannibalism and typically follows a clear size hierarchy. Larger, more powerful hawk species sometimes opportunistically prey on smaller raptors, especially those that are inexperienced, injured, or caught off guard. For example, a medium-sized Cooper’s Hawk has been documented preying on the significantly smaller American Kestrel.
This predation is an extension of their normal hunting strategies, where a larger predator targets any vulnerable animal within its range. Larger Buteo hawks, such as the Northern Goshawk, are skilled bird hunters that may target smaller raptors if encountered. Nest raiding is another common scenario, where a larger hawk preys on the eggs or defenseless nestlings of a smaller species, eliminating potential competition while gaining a meal. The primary factor is a substantial difference in size and strength, making the smaller hawk a relatively low-risk target.
Why Such Predation Is Rare
Hawks generally avoid preying on other raptors because the risk-to-reward ratio is highly unfavorable. Subduing another bird of prey, which is equipped with powerful talons and a sharp beak, involves a high risk of serious injury to the attacker. An injury to a wing, leg, or eye can mean the inability to hunt, which is a death sentence for a wild predator.
The energy expenditure required to hunt and kill a difficult, well-defended animal is far greater than that needed to catch a rodent or a songbird. Since raptors are naturally programmed for efficiency, they will almost always select the easiest and safest meal available. Furthermore, raptors are highly territorial, and most encounters between adult hawks of similar size are focused on aggressive boundary defense rather than genuine hunting. This combination of self-preservation, energy conservation, and the availability of easier prey ensures that one hawk eating another remains the exception in the natural world.