These butterflies are very hard to find in Orange County. This series was photographed in early May 2013 inside the butterfly house at Environmental Nature Center, Newport Beach, California. Butterflies in the wild would normally be aloft this time of the year.

For loads of info about flights, host plants, habitat, etc., please see:
http://nathistoc.bio.uci.edu/lepidopt/pieridae/dogfacm.htm

I am a bit hesitant to post photos of captive insects, but feel this species is thinly represented at Bug Guide. On the other hand, if more such images are welcome, I have plenty of these, plus another series with the same two players.