。
You won't find wild tigers in Africa.
Literal
Wild [gen-の] tiger [topic-は] Africa [in-では] cannot-be-seen-[passive/potential-見られる]-[polite-negative-ません].
見られる is ambiguous — it can be the passive of 見る ('be seen') or the potential ('can see'). In this context, '(in Africa) wild tigers cannot be seen/found' could be either reading. The particle stack では highlights Africa as the discussed location. Interestingly, the sentence is factually accurate: tigers are Asian, not African.