A few years ago I was a volunteer at Moody Gardens Aquarium in Galveston, Texas when I learned of the following dirty job: volunteer scuba divers help clean the penguin habitat. This not only includes the cleaning of the penguin poo off of the rocks, but also involves scuba diving in the penguin swim area to clean the build up of poo off of the glass overhangs (through which guests can watch penguins soaring overhead).
I'm sure Mike could also be involved with the messy "penguin painting" that takes place at Moody Gardens. They let the penguins walk through paint, and then the penguines create "paintings", which are sold in the gift shop. The extra mess comes in when the staff has to help the penguins clean off their paint covered feet.