The area is mountain lions territory. Do not hike alone and take care of kids, if you have some with you. Having seen the grass I guess it is hard to realize them in time. The park suggests not to run away nor to bend, nor to show your back. Be loud and try to appear larger as you are. Thats why it is an advantage to be more than one person. We asked the person at the parking about the mountain lion. He said, he hasn't seen one yet, but I just want to mention it.
Unfortunately we haven't seen one as well.
Seems that there are people not realizing how proud they can be about having such an animal in their environment. Fortunately other care about it! See the link below (I took the photo from there) and support...
There are snakes in the area, including the rattle snake, which is the only snake with poison here. So take care, as they from time to time cross the paths. We saw two snakes, but none was a rattle snake. The day we have been there, they caught one on the camp site.
I took the picture from
CalPhotos! Let me know if it is a problem!
You will encounter lots of ticks, which are nasty as they try to climb on you. My colleagues found three of them each moving on their body (I was lucky and stayed clean) and we saw many waiting on grass to be picked up. Luckily they are much bigger than in Europe and more easily recognized. Anyway, it takes days until you stop checking all the time.
If you are unlucky, ask a doctor! To remove them I found this on the web:
Removing ticks 1
Removing ticks 2