• Question: Do fish get thirsty?

    Asked by 962curm44 to Daniel, Fiona, Hazel, Jacque, K, Matthew on 14 Mar 2018.
    • Photo: K Sasitharan

      K Sasitharan answered on 14 Mar 2018:

      No, fishes do not get thirsty.

      Since fishes live in water, and their gills are in constant contact with the water, there is some kind of osmosis type movement that helps maintain salt and water balance in their body.

      However, this is a reflex and happens constantly without any thirst arousal. Thirst is the desire or drive to drink water. We who live on land do face a constant threat of dehydration and feel thirsty. Since fishes are surrounded water the whole time and there is constant water exchange happening through the gills irrespective of whether the fish desires or not. So, No, fishes do not feel thirsty.

    • Photo: Jacque Cilliers

      Jacque Cilliers answered on 14 Mar 2018:

      It is very hard to know what fish feel. Do they feel pain when they are killed? For a long time scientists thought the answer was no.. but recent research has shown that actually they do. So back to the question – do fish get thirsty? Well… Fish living in salt water do drink, which suggests that they are being told to drink by a feeling which is possibly thirst. Fresh water fish do not drink, water can pass into their bodies from the water that surrounds them. These fish don’t get the urge to drink… therefore they probably don’t get thirsty.
      Great question by they way!!

    • Photo: Hazel Gibson

      Hazel Gibson answered on 14 Mar 2018:

      Haha great question! The interesting answer is that saltwater fish do drink water through their mouths, whilst freshwater fish don’t (they don’t have to as water is absorbed through their gills instead), but the big question is do they feel thirsty?! Do fish have a conscious moment of going: ‘hey, I could really do with a drink right about now!’? Answer… I have no idea!!

Comments

  • Photo: chubbs

    chubbs commented on :

    what happens if the grills are damaged

    • Photo: Hazel

      Hazel commented on :

      Good question! I suppose it would be similar to what would happen if our lungs are damaged – in that gills are essential for both kinds of fish to get oxygen. So I suppose it would depend on the amount of damage to the gills. With a small amount of damage the fish would probably be able to survive, but it would be at a disadvantage because of the injury. If the gills were too damaged the fish would probably die, but I expect from oxygen deprivation before dehydration…

    • Photo: Jacque

      Jacque commented on :

      I’m afraid that if your fish has damaged gills, its probably not going to last long. The gills are a fishes lungs. If your lungs were damaged (severely) than you probably wouldn’t survive. If the gills are only slightly damaged, then it could survive, but may be eaten due to its weakness. I’d imagine that a fish with damaged gills wouldn’t be able to get all the oxygen it needs to run away from predators