rama the elephant , who completed paintings with his trunk , died monday , oregon zoo officials announced on facebook .
zoo officials said rama 's leg was hurt in 1990 , when older female elephants shoved him out of the herd and he went into a moat .
they said rama was euthanized after health problems from the leg injury .
elephant group free the oregon zoo elephants has claimed zoo officials should not have placed rama with the females at a young age .