"Hawk Roosting" is filled with animal imagery. The very first stanza of Ted Hughes's poem provides us with a vivid depiction of the hawk in the title. We see the hawk "sit in the top of the wood." We also see its "hooked head and hooked feet".
In the next stanza, Hughes declares, "The convenience of the high trees!" This expands the image of the hawk, letting us know where it is in nature. We have a hawk sitting on top of a tree as if it was its throne. We might even say that the animal imagery mixes with themes of domination and power. When Hughes says "the earth's face upward for my inspection," it's almost as if the earth belongs to the hawk.
In the third and fourth stanza, we have more animal imagery to work with. We see the feathers of the hawk and are told about its lethal nature. "My manners are tearing off heads," writes Hughes.
We can also talk about the animal imagery by talking about how Hughes explicitly eludes human-centric tropes from his portrait of the hawk. "There is no sophistry in my body," writes Hughes. Later, he adds, "No arguments assert my right."
You might want to think about why Hughes introduces these ideas and how their irrelevance to the hawk reinforce the hawk's animality.