All animals do it, even though talking about it is not considered polite. We humans have sanitized rooms (or not) with air fresheners and running water. Remember how, when the pandemic struck, one of the emergencies was a run on toilet paper? Birds, mostly very different from us, have a different approach to the process. Here are five droppings about bird poop.

1. Bird droppings are important for spreading seeds. When a bird eats a berry, it often digests the fleshy part, but the seed passes through its system intact. When the seed comes out, along with the rest of the poop, the fecal material, which has a lot of nitrogen, serves as fertilizer. Because birds fly, this gives some plants the chance to spread their seeds far and wide. In fact, some plants, such as the wild cherry and the bird cherry, depend on birds to scatter potential offspring.

2. Humans also value bird poop as fertilizer. When bird (and bat) poop is used as fertilizer, it gets the fancier term “guano”. It turns out that the best bird poop for fertilizer is produced by seabirds, probably because they eat mostly fish. And one of the best known places for guano is a group of islands off of Peru, the Chincha Islands, which have a LOT of seabirds (the most common birds are Guanay Cormorants, Peruvian Pelicans, and Peruvian Boobies). I have ridden in a boat past these islands, which are whitish with droppings and still very stinky. The guide explained that only a few people were allowed on those islands, working to export the guano. This Audubon piece details how Peru currently harvests 21,000 tons per year from the Chincha Islands.

3. Guano islands can be of national importance. The Chincha Islands (Islas Chinchas) was of such strategic significance that Spain started a war (1865-1866) over these islands as it tried to take them back from their colonies. The United States even passed a law in 1856 allowing (encouraging!) U.S. citizens to take possession of unclaimed islands with guano deposits. The islands could be anywhere in the world, and were considered eligible as long as they were unclaimed and unoccupied (by humans, that is; birds were OK). Why was this so important? Because the guano was good, not just for fertilizer, but for saltpeter. As saltpeter was a critical ingredient in gunpowder, guano was a strategic reserve.

4. Birds poop differently than humans do. First, birds generally have fewer orifices in the nether regions. Human males have two, one for urination/reproduction and a second for poop, while human females have three, one dedicated to urination, a second orifice for poop, and a third for reproduction. Birds, however, usually have just a single orifice for all these functions, called the cloaca (note that some species, such as ostriches, cassowaries and geese, actually have phalluses). In order to reproduce, male and female birds rub their cloaca together to transfer sperm. Second, birds seem to be relaxed about voiding; they can even do it while flying.

5. Some birds clean their nests. Although places such as the Chincha Islands are literally known and protected for their guano, and obviously the birds using these islands don’t mind the great quantities of guano (the Peruvian booby even uses guano in the construction of its nesting sites), many birds are more fastidious. The nestlings produce fecal sacs, and some parents make a point of removing the fecal sacs. Why, exactly? It could be to reduce the smell, which could attract predators. On the other wing, some parents consume their offspring’s droppings, presumably because the droppings still contain some nutrition.

Enough about poop for the day! Thanks for dropping by.

Victoria Grossack is the author of the Crow Nickels, of which two volumes are available: Hunters of the Feather and Scavengers of Mind. They are about Sol, a thinker-linker crow who has a quest to save the Great Flock from climate change. “Try, and again try, till you win or till you die.” Junkyard Abner, Hunters of the Feather