This bird was in the same aviary as the Double-Eyed Fig Parrot in the childrens zoo, tool me a while to Id but I think this is the correct species and one I've not seen at any other zoo.
Nice photo - thank you for sharing it. The Chestnut-backed Thrush is a species that's fairly new to U.S. Zoos. I believe that most of our zoo birds are descendants of birds imported from Europe; the European Zoo community has been working with this species for more than 10 years. In the U.S., it can be found in about ten zoos including: San Diego (Zoo and WAP), Denver, Tulsa, Riverbanks, Dallas, Disney, Sedgwick County, and Miami. I need to make a trip to Dallas!