Diet of Hawks

Hawks hunt by sight.

Hawks are members of the Accipitridae family, and include both Buteo and Accipiter subfamilies. The hawk is considered the most intelligent bird, based on its innovative feeding habits, According to AvianWeb. These diurnal birds are strictly carnivorous, but different types prefer different prey animals. Location and season also affect the hawk diet.

Prey

Accipiter hawks, or true hawks, tend to prefer birds, such as robins, warblers and sparrows. North American hawks in the Buteo subfamily prefer small mammals, including rats, mice, voles, gophers, rabbits and ground squirrels. Some hawks also consume snakes and insects.

Hunting

Hawks hunt primarily by sight, and have vision equivalent to 20/2--at 20 feet, they can see as well as a human can at a distance of 2 feet. They hunt on their own, capturing and killing prey animals with their talons. Harris' hawks also sometimes hunt cooperatively. Once the hawk captures its prey, it usually spreads its wings over the meal to prevent other birds from stealing it.

Energy

Despite the size difference, smaller hawks actually eat proportionally more than larger birds. Their larger surface area to volume ratio causes them to lose more heat and need more food to compensate. Breeding hawks are also likely to eat more, in preparation for egg-laying. Hawks also increase food consumption during cold weather to compensate for additional heat loss.

Human Influence

Human alteration of hawk habitats affects the availability of food species and the population of hawks. However, not all human influence is completely detrimental. The numbers of Rufous-tailed hawks in Chile have grown as logging fragments the native forest. In New Mexico, hawks in areas with more human influence had easier access to prey. Human alteration of the environment can also kill prey species and limit the availability of nest sites.

Poisoning

As predators, hawks are vulnerable to poisoning from the birds and small animals they eat. Some poisons, such as mercury, can persist in the animal for long periods of time. They eventually build up in the hawk, too. Others, like rat poison, will kill the prey animal in a short period of time, but can still sicken a hawk that eats poisoned prey. Homeowners who poison vermin or dispose of hazardous materials incorrectly may inadvertently affect the local hawk population.

References

• Avian Web: Hawks
• Sea World: Birds of Prey
• Boise State University: Diet and Behavior of Ferruginous Haws Nesting in Two Grasslands in New Mexico with Differing Anthropogenic Alteration
• The Journal of Wildlife Management: Effects of Dietary Methyl Mercury on Red-Tailed Hawks
• Ornitologia Neotropical: The Diet of the Rufous-Tailed Hawk (Buteo Ventralis) During the Breeding Season in Southern Chile