Harris's Hawk

## Description

The Harris's hawk (Parabuteo unicinctus ), formerly known as the bay-winged hawk, dusky hawk, and sometimes a wolf hawk, and known in Latin America as peuco, is a medium-large bird of prey that breeds from the southwestern United States south to Chile, central Argentina, and Brazil. Birds are sometimes reported at large in Western Europe, especially Britain, but it is a popular species in falconry and these records almost invariably all refer to escapes from captivity.

The name is derived from the Greek para, meaning beside, near or like, and the Latin buteo, referring to a kind of buzzard; uni meaning once; and cinctus meaning girdled, referring to the white band at the tip of the tail. John James Audubon gave this bird its English name in honor of his ornithological companion, financial supporter, and friend Edward Harris.

The Harris's hawk is notable for its behavior of hunting cooperatively in packs consisting of tolerant groups, while other raptors often hunt alone. Harris hawks' social nature has been attributed to their intelligence, which makes them easy to train and have made them a popular bird for use in falconry.

## Distribution

Harris's hawks breed from the southwestern United States south to Chile, central Argentina, and Brazil. These birds are permanent residents and do not migrate. They live in sparse woodland, semi-desert, savannah, shrubland, and in some parts of their range in marshes (with some trees), including mangrove swamps.

## Behavior

Harris's hawks are social birds and live in groups. These groups have a dominance hierarchy, wherein the mature female is the dominant bird, followed by the adult male and then the young of previous years. Not only do birds cooperate in hunting, but they also assist in the nesting process. Harris's hawks hunt by day in cooperative groups of 2 to 6. This is believed to be an adaptation to the lack of prey in the desert climate in which they live. These birds use several hunting techniques; in one technique a small group flies ahead and scouts, then another group member flies ahead and scouts and this continues until the prey is bagged and shared. In another hunting technique, all the group members spread around the prey and one bird flushes it out. When Harris's hawks need to communicate with each other, they use very low, harsh sounds. When birds are alarmed, they make a prolonged and harsh “irrr”.

## Diet

Harris's hawks are carnivores and their diet consists of small creatures including birds, lizards, mammals, and large insects.

## Reproduction

Harris's hawks form long-lasting monogamous pairs. It is suggested that females may also exhibit a polyandrous mating system (one female mates with several males); however, this is still debating, as it may be confused with "backstanding" (one bird standing on another's back). Harris' hawks breed throughout the year and may produce 2-3 clutches per year. These birds construct their nests in trees at 5 m of height and line them with soft materials, mosses, grasses, and roots. The female lays 2 to 4 eggs and does most of the incubation. The eggs hatch in 31 to 36 days. The chicks are altricial; they hatch helpless and with closed eyes. They begin to explore outside the nest at 38 days, and fledge, or start to fly, at 45 to 50 days. The young may stay with their parents for up to three years, helping to raise later broods.

## Population

### Population threats

The wild Harris's hawk population is declining due to habitat loss; however, under some circumstances, they have been known to move into developed areas. These birds also suffer from human disturbances and electrocution, because they tend to perch on electrical transformers, and are often electrocuted.

### Population number

According to the What Bird resource, the total Harris’s hawk population size is around 390,000 individuals. According to the All About Birds resource, the total breeding population size of the species is 920,000 breeding birds. Overall, currently, Harris’s hawks are classified as Least Concern (LC) on the IUCN Red List, but their numbers today are decreasing.

### Ecological niche

Harris' hawks are important predators in the ecosystem they live in. Due to their diet habits, these birds control populations of many small mammals, lizards, and birds.

## Fun Facts

John James Audubon gave Harris's hawk its English name in honor of his ornithological companion, financial supporter, and friend Edward Harris.

Since about 1980, Harris's hawks have been increasingly used in falconry and are now the most popular hawks in the West (outside of Asia) for that purpose, as they are one of the easiest to train and the most social. Trained Harris's hawks have been used to remove an unwanted pigeon population from London's Trafalgar Square and from the tennis courts at Wimbledon.

Harris's hawks are the only birds of prey that hunt in groups. Such a unique behavior has earned them the nickname "Wolves of the Sky."

Harris's hawks exhibit an unusual behavior called "stacking" or "backstanding" when one hawk will perch on a cactus, and 2-3 other hawks will stand on his back. In the habitat Harris's hawks live in there is a lack of tall trees and this behavior helps them to spot prey and predators.

Long legs of Harris’s hawks are covered in tough skin and due to this, they are able to perch on cacti!

Harris's hawks sometimes cache their prey in trees so it could be eaten later.