How do Crabs Wee?

Crabs don’t wee like us, so there’s no point asking them to lift the toilet seat up.

Crabs get rid of their waste in a few different ways. Firstly, nitrogen rich waste is diffused across their gills and leaves the body that way.

Crabs also have a very specialised excretory organ called ‘green glands’. These are a little bit like our human kidneys in the way that they get rid of urine, which is high in ammonia.

Strangely though, you find these excretory organs on a crab’s head, near the antennae. At the bottom of these organs is a bladder which releases the fluid through an opening duct in the base of the antenna.

Imagine weeing out of your head?

No, seriously, imagine it.