Hawks are a race from The Legend of Zelda: Twilight Princess. They can be summoned by using Hawk Grass. Once summoned, they can be commanded to grab items or attack enemies. Like most other animals in Twilight Princess, hawks can talk to other animals, including Wolf Link.
When Link first uses a hawk, while he still lives in Ordon Village, Jaggle encourages Link to climb up onto the cliff with him. Once Link has reached the top of it, he asks Link to play the tune on the Hawk Grass, summoning a Hawk. Link must repeat this action a short time later, calling a Hawk to come and retrieve Uli's cradle, which had been stolen by a Monkey. Later, when Link has returned to Ordon Village in wolf form to take the Ordon Sword and Ordon Shield as Wolf Link, he is spotted by Hanch, who summons a Hawk to attack him. Link sneaks behind Hanch to scare him off, stopping the Hawk from attacking him again. After Link scares away Hanch, Link can howl near Hawk Grass to summon a Hawk, who apologies for attacking him.
Using Hawk Grass as Wolf Link will summon a Hawk which tells him of a nearby Treasure Chest or of a Piece of Heart. If Link has collected everything in the area, the Hawk will tell him there is nothing there.
While enlisting the aid of hawks when Link is a wolf can be done in most areas, a notable exception is Lake Hylia, where the only available Hawk Grass is used to initiate Plumm's Balloon Popping Game. Hawk Grass may also be found in the Sacred Grove, though it serves no urgent purpose; the only possible reason is knocking down a nearby Beehive, which can be accomplished with other equipment at Link's disposal at this point in the game. Hawks are also seen at the foot at Death Mountain, where there are Bulblin archers. Hawk Grass can be used to summon a hawk to defeat them without using any items, and from a safe distance where they cannot harm him.
A Hawk can also be seen flying around near Link's House in Ordon Village. Interestingly, if Link sends it in the direction of a Cucco, it will grab the bird and bring it back to Link which he will automatically grab onto.
The Light Spirit Eldin appears to be some sort of giant hawk.