# Why is chicken guano white?

**URL:** <https://boards.straightdope.com/t/why-is-chicken-guano-white/40159>\
**Category:** Factual Questions\
**Created:** [November 7, 2000, 6:40pm UTC](https://boards.straightdope.com/t/why-is-chicken-guano-white/40159 "2000-11-07T18:40:03Z")\
**Posts on this page:** 3\
**Page:** 1

<div class="post-metadata">

**Author:** ![LateComer](https://avatars.discourse-cdn.com/v4/letter/l/b5ac83/32.png) [@LateComer](https://boards.straightdope.com/u/LateComer)\
**Post date:** [November 7, 2000, 6:40pm UTC](https://boards.straightdope.com/t/why-is-chicken-guano-white/40159/1 "2000-11-07T18:40:03Z")

</div>

What is the white stuff in chicken excrement? Just wondering.

---

<div class="post-metadata">

**Author:** ![Skwerl](https://avatars.discourse-cdn.com/v4/letter/s/258eb7/32.png) [@Skwerl](https://boards.straightdope.com/u/Skwerl)\
**Post date:** [November 7, 2000, 9:28pm UTC](https://boards.straightdope.com/t/why-is-chicken-guano-white/40159/2 "2000-11-07T21:28:23Z")

</div>

I don’t know about chickens, but I’ve read that the white stuff in bird droppings is actually their urine, and the black/brown lump is the real poo.

---

<div class="post-metadata">

**Author:** ![Colibri](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/colibri/32/1841_2.png) [@Colibri](https://boards.straightdope.com/u/Colibri)\
**Post date:** [November 7, 2000, 10:55pm UTC](https://boards.straightdope.com/t/why-is-chicken-guano-white/40159/3 "2000-11-07T22:55:13Z")

</div>

All birds, like reptiles, excrete uric acid, which is white and relatively insoluble. Mammals excrete urea, which is more soluble and requires a lot of water to flush out. The white in bird droppings is their semisolid “urine.”