One day I was out there working on the tanks, answering stupid questions (like "Is that fish gonna bite you?" or "Is that fish dead?"). Then an young-adult Special Ed group came through and after they passed, the stench was born...
They had stopped in the other area of the aquarium and reptile complex and one of the poor goofy bastards was obviously not trained as well as most dogs. He crapped in his pants and shook the crap out the leg to land next to his foot. He told no one and was in the middle of the pack. The herd of droolers then stampeded into the Tropical Rainforest Habitat and brought pieces of the inappropriate turd with them as none of them seemed to avoid it, but rather all seemed to make a point of doing some shoe painting instead.
This would have been bad enough, but the story continues... not only was there corned sausage trampled into the carpet, but the floor of the Tropical Rainforest Habitat is heated from below the tiles. The crap on the shoes transferred to the tiles where it was gently ripened to a stench-multiplying 120 degrees. Couple this with nearly 100% humidity, and the ingredients for disaster are mixed together.
The crowd managed to find their way out of the building in as orderly a fashion as can be expected from 40 crap-laden morons in a zoo on a quick and rare escape from their cages or pens or whatever. But their memory lives on, as you can still get a whiff of the funk they left behind. Steam cleaning and shampooing the carpet had limited effect so it was replaced, but the tiles were cleaned and scrubbed even now they still retain a reminder of that fateful day when that sweet retard gave one lucky turd its freedom.