Walking through the Webs

When I visited the National Zoo as a kid, there was one exhibit that always fascinated me - and terrified me.  Walking through the (now closed) Invertebrate House, the last exhibit was the butterfly walk-through.  What's so terrifying about that, you may ask?  Nothing.  Nothing at all. 

Except that to get to it, you had to walk past the penultimate exhibit - a colony of massive (to a small child) orb weaver spiders, sprawled prominently across their webs.  Spiders always scared me as a kid, which made the Invertebrate House (and especially its goliath bird-eating spiders) a special kind of spooky for me.  Unlike the bird-eater, however, there was no glass between me and the orb weavers.  There was nothing but air.  If I'd reached out, I could have touched one.  Or, as I feared, it could touch me.

Though invertebrates are typically displayed in glass cases, there are some opportunities for visitors to have more... intimate encounters with them.  Butterfly walk-throughs and aquatic touch tanks are the most common, though I've also seen open-air spider exhibits and leaf-eater ant colonies (the ants having glassed in habitats at either end of a building, and being able to traverse an open, exposed path in between as they haul their leaf fragments back and forth). 

Such exhibits offer unique, more intimate encounters with animals.  They also do pose an element of risk.  Not so much to the visitor - it's not like anyone is having playful, hands-on experiences with bullet ants, box jellies, or black widows.  The risk is to the invertebrates, which tend to be small and fragile and could easily be damaged or killed by a careless (or malicious) visitor.  Such exhibits should be under staff supervision to protect the animals when visitors are present.

There is also the risk of escape.  Inverts - especially plant-eating insects - are some of the most tightly-regulated animals in zoos and museums due to their potential threats to agriculture.  Even for "harmless" species, there is the risk of animals getting out.  That's why butterfly walk-throughs have vestibules, usually with mirrors, to allow visitors to check themselves for hitchhiking butterflies before they depart.