>> you want some water? good boy! >> reporter: panda curator laurie thompson has been beenhing over bei bei since the day he was born, but at four years old he's all grown up and under an agreement with china must now join their panda peeding program. we got a sneak peek as thompson acclimated him to a steel crate like the one that will carry him to china tomorrow aboard a fedex lane with his picture on the side. >> once i have to say good-bye, that's going to be tough. >> reporter: bei bei could be the last panda at the national zoo. his older brother and sister are already in china. his parents will remain in d.c., but the zoo says it's unlikely his mother can have another cub. the zoo director believes this is not the end of an era. we started 47 years ago with giant pandas, and our vision would be to continue working tth the chinese counterparts for another 50 years if we can. >> reporter: there are only about 1,800 pandas left in the wild. a fahope is that bei bei will