Hawks, like all raptors, are birds of prey, and their young require a specialized diet to support their rapid development. A baby hawk, technically called an eyas while still in the nest, is entirely dependent on its parents for a high-protein, carnivorous diet. This intense feeding period is necessary because these birds must grow from a small hatchling to a near-adult size in a matter of weeks, developing the muscle, bone, and feathers required for their first flight.
The parents assume full responsibility for hunting and procuring all necessary food until the young bird can hunt for itself. This dependency means the nestling’s diet directly reflects the adult hawk’s hunting success and the local availability of prey. The nutritional demands are high, requiring adult birds to maintain a high-intensity hunting mode.
The Primary Diet of Nestlings
The diet consumed by hawk nestlings is carnivorous and varies significantly depending on the species and the environment surrounding the nest. For large, generalist hunters like the Red-tailed Hawk, the primary food source is small mammals. This includes common rodents such as mice, voles, rats, and squirrels, which provide a calorie-dense meal for the growing young.
Other prey items are frequently included in the diet, such as snakes, lizards, and large insects, depending on what the parents can find easily. Studies on the Red-shouldered Hawk, for instance, show a diverse nestling diet including small mammals, reptiles, invertebrates, and amphibians, though mammals usually make up the largest percentage. This opportunistic approach ensures a steady supply of protein for the young throughout their nestling phase.
In contrast, other species have a more specialized diet reflecting their distinct hunting styles. Accipiters, such as the Cooper’s Hawk, are known as “bird hawks” and feed their young primarily on small birds, including songbirds. The parents of these species are adapted to pursuing prey through dense foliage, which determines the type of food delivered.
Parental Roles in Prey Preparation and Feeding
For the first few weeks after hatching, young hawks cannot tear apart prey themselves, making parental preparation essential. The adult male typically focuses on hunting and delivering the captured prey to the nest or to the female nearby. The female, often the larger of the pair, then takes on the role of feeding the nestlings directly.
She meticulously tears the prey into small, bite-sized pieces, which are then passed to the young birds one by one. The size of these morsels is small to ensure the hatchlings can swallow them without choking. The softest parts of the prey are usually offered first to the youngest chicks, as their digestive systems are still developing.
This dedicated feeding continues for the first two weeks, demanding the female’s full attention and requiring the male to maintain a high hunting rate. As the nestlings grow, the feeding frequency remains high, and the size of the meat pieces offered by the female gradually increases. Eventually, the nestlings develop enough strength and coordination to begin self-feeding from a whole carcass delivered by the parents, marking a significant step toward independence.
The Transition to Independent Hunting
The stage when the young hawk leaves the nest is known as fledging, which for a Red-tailed Hawk typically occurs between 42 and 46 days after hatching. Even after taking their first flight, these fledglings are not yet nutritionally independent and remain reliant on the adults for food for an extended period. They often stay associated with the parents, sometimes for as long as ten weeks post-fledging, waiting for food deliveries.
The parents gradually change their delivery method to encourage self-sufficiency in the fledglings. Instead of bringing torn pieces directly, the adults may drop whole or partially prepared prey near the young bird, forcing it to handle and consume the meal itself. This shift introduces the young hawk to consuming whole prey, including the fur, feathers, and bone, which leads to the formation of regurgitated pellets.
The transition to hunting is a slow, learned process that begins with simple flights and mock attacks on objects in the environment. The young bird’s ability to consistently capture vertebrate prey may not develop until around seven weeks after fledging, meaning the parents must continue to supplement the diet during this critical learning curve. The eventual goal is for the juvenile to successfully hunt its own food, marking the end of the parental care period.