I also just got off the phone with them. It is $15, but apparently, only on the weekends. Feeding time is at 12:00pm. They recommend getting there early, as tickets are sold beginning at 11:00a. Thank you!
It's 15$ per person to feed the giraffes. Times very depending on week days/weekends. It's best to check with Guest Services upon arriving in the Zoo front entrance for specific times.
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