Hello! Welcome to the Forum!
You are in my neck of the woods, I live in Santa Cruz, CA. Hollister is just down the street.
I recently caught 4 Pacific Chorus Frogs from my backyard. I would highly recommend them for your pond. They are native frogs to our area and would enjoy your natural backyard.
Have a look at the Pacific Chorus Frog Care guide on the left navigation bar. I believe you will enjoy these very friendly and musical frogs.