Why do birds pee know

Why is bird droppings white?

White bird droppings are actually less poop than urine. At least a mixture of both. Birds often excrete excrement and urine at the same time and only have one body opening for both. The pile that the birds leave behind is rather dark-grayish at the edge, but white in the middle. The dark is the actual feces, the white in the middle is the urine. If the urine predominates, then everything is white.

And why is the urine white and so solid at the same time?

Birds' urine is relatively solid because they drink very little water. They hardly drink in advance, because that would make them unnecessarily heavy and hinder them when flying.
But why is this bird's urine white and not yellow as it is with us? There are two differences. First: Our urine is made of urea and it is colorless and transparent. Bird urine, on the other hand, consists of uric acid, and it has a white base tone. Second: Human urine contains red blood cells - highly diluted, they give it its yellow color. The red blood cells in our body are regularly changed and they are disposed of in the urine. Birds keep their red blood cells longer and therefore shed them less often. So there are no red blood cells in the urine of birds, so the urine retains the white color of uric acid.

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