I had a pet bird called a Whinky-Whankey bird from South Africa, very unusual as it's foreskin was attached to it's eyelids...so every time it winked...it wanked.
I once watched a documentary about young whales as they began to enter adolecence, before pairing up with a mate. Each year, around the mating season, when they were naturally getting horny, they would make for a particular beach which was lined with smooth pebbles & would masturbate by rubbing their erect penises against the pebbles. (Incidentally, as a point of interest, the proper name for a whale's penis is a Dork).