Her attention and focus had drifted too far, and when she saw movement it was too subtle and nearly out of her range. Her head twitched towards it though, that gaze that had helped birds find fish and wriggling worms sweeping over the trees in front of her with a critical eye. This big mouse, or whatever it happened to be, was smart.
There was no movement for a moment and her eyes turned to the branches around her that could be impeding her hunt. The question was, was it better to go higher or lower this time? It was being quiet, and probably hadn't left the tree yet because she would have heard the branch bounce again.
Was he going up then? A bad plan, because the branches she had to fight to get to him the easier it would be on her. Lower to the ground would be better now that she wasn't a coyote, perhaps it had a burrow somehow it was planning on hiding in. That wouldn't do her any good.
Briar hopped down on a branch below in the tree she was in, glancing around to try and find him. At this point she was preparing to shift back to a human and launch herself at him no matter how high up he was, though that could have very different results, something she was far too familiar from trying to chase cats down alleyways as a kid.