It's a trail so yes, stand up and walk is the thing. Southern California is home to hundreds of bird species. I recommend a Google image search for the best details.
Yes, there is space. Birds? I saw crows often, not special birds.
Yes. The trail is well maintained and is quite wide for most of the journey to the peak. There are waterfowl like coots around the lake, but there are plenty of other species in the surrounding area.
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