Horticulturalist

It's been said that the animals are the stars of the zoo, but plants set the stage.  Before most visitors see a single animal upon entering the gates, their first impressions are already being formed by the landscape that they walk through.  In some cases it's formal gardens of flower beds.  In others it's manicured lawns.  In other's still it's wildness, either native habitat or a landscape that is meant to be evocative of the habitats from which the zoo's animals come.

And that's not even counting the plants and landscaping within the individual animal enclosures.

Responsibility for the zoo grounds falls to the horticulture team.  They are responsible for the upkeep on the plants on zoo grounds, often both in and out of the exhibits (though at some zoos keepers assume responsibility for the plants within animal habitats).  Many non-animal facilities have horticulturalists on staff, from business parks to universities to private estates to, of course, botanical gardens.  The duties and challenges of the zoo horticulturalist go beyond making the grounds aesthetically pleasing, however.  They are also responsible for maintaining plants that help provide comfortable living conditions for the animals.  That means choosing and cultivating plants that are  attractive and appealing for the animals.

Zoo animals come from all over the world, and, not surprisingly, so do the plants that the cohabit with.  Not all of those plants can thrive in the climates that we keep animals in, and while you can move a giraffe inside for the winter, it's not as easy to that with an Acacia tree.  So horticulturalists must work with plants that may not be natural to the animal, but will grow and thrive under the local climatic conditions.  They'll have to be plants that can take some abuse and attention from the animals - browsing, climbing, scratching, etc.  And besides keeping the plants safe from animals, they have to keep animals safe from plants (for a great fictional example, the original Jurassic Park features InGen's Stegosaurus repeatedly get sick from browsing on toxic plants). 

Many zoos tack on "and Gardens," or "and Botanical Gardens" to their name, and while I feel that some of them due it a little lazily, there are others which really are true botanical gardens with an equal emphasis on their plant collections, both in terms of size and scale of collection and the nature of the work they carry out.  At some zoos, the plants featured might even be more endangered than many of the animals.  The breadth of plant species on display (or cultivated for food on grounds) requires a tremendous degree of knowledge.  Like the zookeeper, however, much of the horticulturalists time and energy is usually taken up by the botanical equivalents of shoveling poop and chopping diets - mulching, raking, pruning, weeding, and watering.