Bactrian camels.The nearest a zoo can come to having a trouble-free animal.The simplest enclosure with the most minimal barrier, even a 50cm ditch, will keep them in place.Simple, plain diet.Nerves of steel.Can go through its lifespan without requiring one veterinary intervention.Easy to keep happy - just having a good view of the comings and goings of other animals, visitors and staff is fine.Basic shelters sufficient at night.Always visible - huge visual impact and "presence" for visitors.Can be a calming presence for nervous animals kept nearby e.g. antelopes.Staff do have to be careful though- they have a savage bite which they can unleash unexpectedly.Other than that , "great value" for a zoo.
