Complex sentence: It is one of the few places in the world with white lions (a separate species: the white lions are not albinos), and has had considerable success in their breeding; these are more sought after than tawny lions by other zoos.
Split into simpler sentences: It is one of the few places in the world with white lions. The zoo has had considerable success in the breeding of white lions, which are more sought after than tawny lions by other zoos.