In your opinion, what is the symbolic significance of the hawk?
I'm not sure I understand your question. To which part of the poem are you referring when you say "the hawk"? I can only assume it is a typo and you are referring to the eagle in the title. If not, retype your question with more clarification.
Here is the text of the poem:
He clasps the crag with crooked hands;
Close to the sun in lonely lands,
Ringed with the azure world, he stands.
The wrinkled sea beneath him crawls;
He watches from his mountain walls,
And like a thunderbolt he falls.
Consider the description of the eagle - crooked hands. This suggests he is old. The idea of old is repeated in the description of the "wrinkled" sea. The eagle could represent an elderly person, who is still grasping the world like the Eagle grasps the mountain. His ability to fly is the possibilty of the spirit soaring above the world. The spirit can only soar, however, when the eagle lets go. When we "let go" of the world, our spirit will fly into the heavens. Tennyson's poem is spiritual in nature.