what droppings are powdery
Here you can see bat droppings sized by a pen. Bat droppings (guano) are very dangerous to humans. They looks similar to mouse droppings, but when touched they break apart into a powdery substance. This powder then becomes airborne, and once inhaled it can cause a terrible respiratory disease called Histoplasmosis. Histoplasmosis is the most severe danger of bat droppings, but disease is not the only risk.