Do Fish Pee?

[burgerchow]

ok. slow day at work. Just started thinking about fishes. We all know they poop, but do you think they pee? I'm thinking they use a type of osmosis to expel excess liquids out through their skin, but what do I know?

[Mandosh]

Short answer is yes.

[Snaz]

They sure do.
http://www.infovisual.info/02/033_en.html

[MarkoD]

but what do they drink?

[Mandosh]

Saltwater species drink sea water to make up for the water they lose to the environment via osmosis.

Freshwater species gain large amounts of water through osmosis.

[burgerchow]

OK, I've caught tons of fish, and when gutting them, never have seen a pee bladder. Where does the pee come out? Same place as the poop I guess?

[Reef_Geek]

osmoregulation (fluids/salts/dissolved gases) primarily exchanged at gills and secondarily through GI system

[Mandosh]

OK, I've caught tons of fish, and when gutting them, never have seen a pee bladder. Where does the pee come out? Same place as the poop I guess?

You'd never see the urinary bladder cleaning a fish, but they do have one. In the vent of the fish there are two openings; one for the "poop" that is connected to the digestive tract (anus), and the second (urogenital aperture),where the "pee" comes out, is connected to the urinary and reproductive systems.