04 of Trilemma Adventures, a collection of 1-2 page adventures by Michael Prescott.
From the situation summary:
"In an underground cavern vast beyond measuring stands the Midden, a fossilized dung heap produced by a nest of dragons far above on the roof of the cavern. The nest now abandoned, the midden remains, picked over by scavengers of every stripe.
The outer cavern is completely dark, except for the odd glint of fire from beetles on the slopes."