You might think that Jeffers was describing the same hawk if he hadn't added that essential S and broken the poem into two (unequal) parts. Each part focuses on a different occasion, but they're both very related.
Here's the thing. It's hard to know what a poet's intention is just by reading a poem. Maybe Jeffers wrote two poems about hurt hawks at different times and one day was looking through his files and said, "hey, these two poems would work great together." If that's the case, then the two parts can help you realize this sort of thing isn't a one off. Here's a guy who makes a practice of studying the animals around him. They make him think.
The lines are unrhymed and mostly in free verse, and are of varying lengths. It makes sense that the content of these lines is about sky and limits, both of these creatures' mobility and, finally, their lives. The lines alternate, long and short, making you think of duration and abrupt ends.
Taking a (wide) page from Walt Whitman's book, Jeffers is famous for the long line that sometimes has to wrap around to fit. Such long lines are offset by shorter bits, which break up the look of the poem, but also call attention to some of its key ideas:
No more to use the sky forever but live with famine
And pain a few days: cat nor coyote
Will shorten the week of waiting for death, there is game without talons. (3-5)
You know how time seems to fly when you're having fun, and drag when you're at the dentist? It's all based upon perspective. What may be a short time for a cat or coyote might seem like eternity to a hurt hawk.
Jeffers' earlier verse was in strict meter and rhyme, but he felt that was conventional and later was totally embarrassed by his earlier work, to the point where he wanted to drown the early poems. But you still can hear iambic echoes here and there in this poem:
I'd sooner, except the penalties, kill a man than a hawk; (Line 18)
The classic meter of this line makes it oh so quotable. There's something about the old classic forms that makes whatever you say all the more elegant. It's like the saying that the phone book read in French sounds romantic. Almost anything given meter will seem, well, more poetic. It adds authority to any declaration, and this line definitely stands out among the rest
The combination of free verse and more controlled meter could remind readers of the range and limits of the hawk's own freedom. In any case, the variety certainly keeps things lively.