Optics Mag is reader-supported. When you buy via links on our site, we may earn an affiliate commission at no cost to you. Read more.

Do Birds Pee? Everything You Want to Know!

Last Updated on

sparrow in a branch

There are a lot of obvious differences between humans and birds. We’re mammals and have all the characteristics that come along with that, so we have hair, give birth to live young, and we produce and feed milk to our young. Birds, on the other hand, are part of the aven family. They have feathers, lay eggs, and they do not have mammary glands so do not produce milk.

Another major difference, although perhaps less obvious, is the way that birds and humans urinate. We all know how humans do it, but bird urine is essentially combined with their poop. It is, in fact, the uric acid which is converted from nitrogen and then combines with solid fecal matter and then excreted when the bird poops. It is this same acid that makes bird poo white.

hummingbird divider

Birds And Bladders

Human kidneys take all the excess nitrogen from our bodies and then store it in the bladder as urea. When we empty our bladders, this is expelled as urine through the urethra.

Although birds, apart from the emu, do not have a bladder or urethra, they still need to expel unwanted nitrogen. Instead, the nitrogen is converted into uric acid. This acid combines with solid matter and is excreted when the bird poops. It’s what gives the poop a white color and it is how birds wee, even if it isn’t what we would consider urination.

It is believed that birds deal with waste nitrogen in this way because it saves weight, which is essential to birds that need to be streamlined to fly.

sea bird flying
Image Credit: Ian Dyball, Shutterstock

Can Birds Pee While Flying?

Because birds combine urine and feces and expel it all at the same time, and we all know that most birds can poop while flying, they can indeed pee while in flight. Pigeons and geese are notable exceptions to this rule. When these birds fly, they tuck their feet under their anus, so if they were to poop and urinate while flying, they would likely do so on their own feet or they would have to move their foot position and risk poor flight performance. They will poop while foraging and while they are sitting on ledges, but thankfully, geese do not poop while in flight either.

What Animals Do Not Pee?

Strictly speaking, mammals are the only animals that create a yellow urine liquid like humans do. As such, no other animal pees in the same way. In most other cases, urine is dealt with in the same way as with birds. It gathers and collects fecal matter before being expelled via a cloaca.

All animals need to get rid of the toxic liquids and other toxins in their bodies, they just have different ways of doing it.

Eastern Bluebird
Image Credit: Steve Byland, Shutterstock

Do Birds Pee?

Birds do not pee in the same way as humans do, primarily because they do not have a bladder or urethra. They do still need to expel waste nitrogen from blood cells, however. They do this by converting nitrogen into uric acid, which combines with solid matter to create a gooey paste, and then expel this as poop. Most birds can excrete while in flight, with the notable exception of pigeons and geese.

Looking for more interesting bird articles? Take a look at:

Featured Image Credit By Pixabay

About the Author Robert Sparks

Robert’s obsession with all things optical started early in life, when his optician father would bring home prototypes for Robert to play with. Nowadays, Robert is dedicated to helping others find the right optics for their needs. His hobbies include astronomy, astrophysics, and model building. Originally from Newark, NJ, he resides in Santa Fe, New Mexico, where the nighttime skies are filled with glittering stars.