Just Browsing

I'm not a great joke teller.  I try, but then I usually get embarrassed midway through at the cheesiness of the joke and rush my way through.  Also, I sometimes try for something too esoteric and it misses the mark with my crowd.  Take this one, for instance...

A giraffe walks into a bookstore.  It spends several minutes poking its face into the topmost shelves before a clerk finally walks up and asks, "Need help finding anything?"  "No, thanks," the giraffe replies.  "I'm just browsing."

It's a zookeeper pun - "browsing" is the act of foraging for leaves, as opposed to "grazing," the act of eating grass.  Giraffes and okapis are browsers.  Moose are browsers.  Sumatran rhinoceroses are browsers.  Zebras and wildebeest and bison are grazers.

In the wild, browsing mammals spend a whole lot of time, well, browsing, so it's not surprising that in a zoo setting, we would want to replicate that behavior.  The problem is that herbivores have huge appetites, and even in a relatively large enclosure, it won't take too long for most plant-eaters to gobble up every scrap of edible greens.  The task then falls to us, the keepers, to find fresh foliage and harvest it for the animals.  These leafy treats are called "browse" by the animal care staff.

For some keepers, the hunt for browse is one of the most time-consuming chores of the week, with eyes always peeled for freshly downed branches, especially after a storm or when tree trimming is being done (the larger branches are also sought after eagerly by bird and primate keepers, who wish to use them for perching). 

Few keepers feel the demand as intensely as those who care for giant pandas - bamboo is just another flavor of browse, though in this case it happens to be the only flavor that the animals in question prefer.  The US zoos that maintain giant pandas have staff members - either keepers, nutritionists, or horticulturalists - who basically just spend their days harvesting bamboo.  Sure, you could give the pandas a pan full of biscuits with some cut produce, the same as you would an Andean bear or an American black bear, and it would probably be fine, nutritionally.  A goal of the zoo, however, is to replicate natural behavior as much as possible, and for pandas a big part of that consists of sitting on your butt and eating all of the bamboo within arm's reach, methodically plodding your way through it.  Well, not "all of the bamboo" - pandas are obnoxiously selective, and a lot of that tediously collected bamboo ends up being shunned and tossed.

Elephants are another high-maintenance browser, though they tend to be less selective.  For them, it's more a question of bulk - we're talking whole trees here, not a few leafy cuttings.  Eating these trees is great physical and mental exercise - the lifting of the trunks, the manipulation of the objects, the discernment between what you do and don't want to eat, and in what order.  It can keep the animals entertained and occupied for hours, which is the point... well, that and the nutritional benefit.

In the keeper offices of almost any zoo, you'll find a list of approved browse posted somewhere, meant to help keepers determine what is and what isn't safe for their charges to eat.  This requires at least some knowledge of tree identification, which a lot of keepers tend not to have the patience for.  As a result, many will feed out a handful of species which they know and can identify readily in their area, such as mulberry and willow.

It's a pity that browse is such a pain to find and collect in sustainable quantities, because the benefits for the animals are great.  For some species it's a great occasional treat.  For others, like our beavers, I wish I could give it twice daily.  Browse promotes good nutrition, natural behavior, makes for interesting visitor experiences, and takes up a lot more of the animals' time than grain and hay does.  If my zoo had the space - and assuming I could be restrained from building more exhibits in it - I would love to create a browse orchard, full of trees that I could harvest to feed my hungry critters.

As that is not happening any time in the near future, I'll just keep my eyes peeled as I drive to and from work, especially after a storm.  You never know what leafy green surprises are waiting just around the corner.