Hold Onto Your Stuff...

 I've never been very good with heights, but whenever I visit a zoo that has a skytram (such as at San Diego Zoo or Kansas City Zoo), especially one that passes over animal exhibits, I usually cave in and end up taking it.  In those cases, my biggest worry isn't falling to my death.  Instead, I'm usually more fixated on not dropping anything.  I have major worries about having something slip from my hand or my pocket and fall into an exhibit below.  Not only would I not want to lose my phone, my camera, my wallet, or my keys, but I'd hate for it to fall into an animal's enclosure and potentially have something happen to it that causes the animal to become sick or injured.

Of course, you don't need to be several stories above an exhibit to drop something in.  Nor are all of the foreign objects that find their way into animal enclosures introduced to that environment accidentally.  The zoo histories are full of animals which have sickened or even died from ingesting coins, keys, and other items.  Water-filled exhibits seem to especially attract this sort of thing - something about a body of water compels people to toss things into it.  Hippos, with their wide, gaping mouths, further seem to invite people to toss things into them, and many hippos have chocked on toy balls.

Here with a reminder of the perils of dropping or tossing objects into zoo habitats is Zoo Miami, with a message concerning their Cuban crocodiles Leroy and Princess (spoiler alert, everyone seems to be okay).  Photo credits to Ron Magill.