this actually happened to me as well about a week ago, also a buck, coming down fern dell. i ride almost every day in the park, and i always have an eye out for coyotes. i see 1-3 every time i ride up there, i think because it's usually around dusk. i've come close a few times to hitting one, but any more i try to take my turns a bit wider where i've seen them in the past. that would be a death blow for the coyote for sure, and tha wouldn't be too cool.
Once when I was riding home down Westridge fireroad, a coyote jumped onto the fireroad and ran beside me for about half a mile before going off into the brush. I never felt threatened as he seemed to be playing along with me. I've heard from riders the same thing has happened to them on Westridge fireroad.
It was the end of a pretty strange commute because on the ride into work I saw a couple on horses riding with their two dogs and their goat and on the way home I saw a deer and the coyote. Not the normal LA commute.
-ss