I found quite nice website about how North American zoos help elephant conservation:
International Elephant Foundation - Asian and African Elephant Conservation
International Elephant Foundation - Asian and African Elephant Conservation
Current In Situ Projects, African elephants:
Kalama Community Wildlife Conservancy: Community Conservation of Elephants in Northern Kenya
Support to the Enforcement of Poaching Control and Bush Meat Trade
Children and Elephants of Boromo Region, Burkina Faso
Lake George Marine Ranger Station: the Waterways Project, Uganda
Movement, Population Distribution and Social Dynamics of African Elephants Waterways, Uganda
Asian elephants:
Community-based Elephant Conservation in Cambodia
Mahouts and Their Elephants Working as Conservation Response Units in Sumatra
Sumatran elephant’s dietary ecology, movement and habitat use: Using ecological approach to save endangered Asian Elephant and their habitat in Sumatra, Indonesia.
Conserving Asian Elephants and Human-elephant Conflict Mitigation in Kaeng Krachen National Park, Thailand
Saving Elephants by Helping People, Sri Lanka
Support for GAJAH the publication of the IUCN/SSC Asian Elephant Specialist Group (AsESG)