Heidelberg has two new yellow South American songbirds that are very rare in zoos: Yellow Oriole (Icterus nigrogularis) and Yellow-headed Siskin (Spinus yarrellii).
The orioles are kept in South America aviary near the elephant house. They came from the Wilhelma. Heidelberg is (according to ZTL) the 4th zoo that keeps them. (The others See Wilhelma, Walsrode and Bird Paradise).
The siskins are (according to ZTL) unique for Heidelberg.