Harris Hawk (Parabuteo unicinctus)

The Harris Hawk is native to the central part of the Americas, southern North America down throughout much of South America. There is some evidence that they are spreading their range further into North America. Like many other raptors, the population of Harris Hawks is currently on the decline. There are two subspecies of Harris Hawk, Parabuteo unicinctus harrisi is found mainly in the North American down through to northern South America & generally referred to as Harris Hawk & Parabuteo unicinctus unicinctus found mainly in South America & is generally referred to as Bay-Winged Hawk.

The Latin name Parabuteo unicinctus means similar to a buzzard (Parabuteo) with single stripe (referring to tail). The ornithologist, Audobon, gave the bird the name Harris Hawk, after his friend Colonel Harris.

In the wild, Harris Hawks prey on small rodents, such as rats & mice, lizards, small birds (often taken in flight) & small mammals, such as young rabbits. If prey is scarce, they have been known to feed on carrion.

In the wild Harris Hawks will live up to 12 years, in captivity they can live for twice that long.

Very often, a female Harris Hawk will mate with two males & the nest may be made in cooperation of several other birds. Nests are made in the tops of trees or on the top of a tall yucca or cactus. Up to 5 eggs are laid & incubation is done by the female (33-36 days). Feeding of the young is done by the female & both of the males she mated with. The young are fully fledged in 7-8 weeks from hatching, though the young may stay with the parents for up to 1 year. Sometimes two clutches of eggs are laid in a season, between early March to late June.

At least one study has shown that the polyandry (mating with more than one male) exhibited by the female Harris Hawks is not due to an imbalance in the ration of males to females, the ratio is roughly 50:50. Whilst it is not certain why the polyandy exists, one theory suggests that the amount of available food available may be an issue. Some studies have shown that in areas of large amounts of food, the males (who usually provide most of the food during the early part of the breeding season) are more likely to mate with more than one female (polygamy) as they are able to provide food for both. In areas of low amounts of food, polyandry is more likely, as the chances of survival for the young is improved with two or more males providing the food. As Harris Hawks naturally hunt cooperatively & are usually more successful hunting in this manner, this has been suggested as a major reason for the female Harris Hawks taking two mates.

Harris Hawks are one of the few broadwinged hawks that will readily hunt in a team (sometimes called a cast), when they are socialised with each other. When hunting as a team, they will take turns in flushing the quarry while the others wait & attack when flushed. This enables the hunting to carry on for longer than usual, often with the prey tiring before the birds.If the prey hides in bushes, then some of the group will attempt to go in after the prey, while the rest wait on the other side for the prey to rush out. In the wild, this cooperative hunting is most often done during the winter months when prey is scarce, the prey will be equally shared at the end of the hunt, often with the juveniles being given the first share, while the adults wait.

Since being introduced into falconry in this country around 35 years ago, Harris Hawks have become one of the most popular falconry birds here. Due to its size, intelligence & temperament an ideal beginner's bird (some think it is not suitable as a beginners bird, because it is too easy to train, & so the beginner actually learns very little). Although generally amiable, can be temperamental, females being particularly prone to aggression in adulthood and young birds can have very anti-social manners. Early imprinting on humans, & occasionally when kept singly, partial imprinting on the owner, associating people with food, can produce birds that scream for food when the owner is in sight. Juveniles tend to grow out of this after the first moult, but it is not guaranteed.

In the wild, Harris Hawks have been seen to indulge in "stacking" - sitting on each others backs, often up to three high, either on the ground or on the top of a cactus. It is not certain why they do this, though it has been suggested as either due to lack of roosting space or as a method of still hunting, giving slightly more height & so further distance seen, in desert areas which do not have the benefit of trees or poles to sit on. (Both dubious explanations, if you ask me)

IUCN Red List Status :

Least Concern (LC)

AOU Data :

Species Number : 335.0
Alpha Code : HRSH
Common Name : Harris's Hawk
Longevity Record : 14yrs 11months

Also Called :

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