Do cicadas pee?

More than a few people have asked Cicada Mania: “do cicadas pee”? Absolutely, cicadas do pee. There are a couple of reasons why:

• They pee to eliminate excess fluids taken in while drinking xylem (1).
• They pee to eliminate non-essential amino acids (2).
• Underground, they could use excess fluid to help moisten and remold their tunnels & cells (2).
• They might, in some cases, even use it to keep ants from attacking… (3)

You may have been under a cicada-filled tree on a sunny day and felt a sprinkle or two. Don’t worry, it is just watery tree sap (xylem) passed through a cicada.

A detailed explanation of the experience courtesy of Les Daniels:

I’ve experienced this several times where I was on the receiving end of this artificial rain. When many cicadas congregate on warm days, they feed on the tree fluids and often urinate ‘piss’ while doing so. This bug urine is called ‘honeydew.’ The little buggers have pelted me several times while I was observing a little ‘too’ close. It isn’t uncommon. Lastly, the ‘honeydew’ does not stain or stink. In fact, it feels like raindrops.

Some cicadas seem to pee more than others, for instance, the Chremistica umbrosa of South-East Asia. If you walk under an umbrosa, you will need an umbrella! (The Latin root of both words, umbr means shade). Here is a video of Chremistica umbrosa:

Sources:

¹ Records Of The Cicada, Chremistica Umbrosa (Distant, 1904) In Singapore, With Accounts Of Its Mass Emergence (Homoptera: Cicadidae: Cicadinae), Tzi Ming Leong, Aminurashid and Benjamin P. Y-H. Lee, NATURE IN SINGAPORE 2011 4: 163—175, 15 June 2011

² The Ecology, Behavior, And Evolution Of Periodical Cicadas, Kathy S. Williams and Chris Simon, Annu.Rev. Entomol. 1995. 40:269-95

³ The documentary The Queen of Trees by Deeble & Stone features a segment about Fig Cicadas, that expel pee, sweet with the phloem sap of the fig tree, which is enjoyed by ants and monkeys, which has the side benefit of keeping those predators and nuisances away.