Scroll through the gallery to see all of the pop superstar's past hookups and relationships.
Speculation the pair attended the event as a date was put to rest when Dormer, who openly expressed his fluid sexuality on Big Brother, came out as gay for the first time with boyfriend Ash Toweel this week.
The ambassadors walked the khaki carpet in honor of Steve Irwin, and in support of DISCLAIMER: We have made every effort to verify that the images and multimedia content displayed on this page are free to use for reporting purposes.
Hunted for parts and pelts, there are fewer than 4000 wild tigers left.
Therefore, tiger conservation is now more critical than ever to protect these cats from extinction.
Bindi, who lives full-time on the Australia Zoo grounds in Queensland, has 1.3 million followers on the photo-sharing website whilst Elissa, who works as a naturalist and environmental writer, boasts a whopping 190 thousand fans.