Can Fish Detect Sickness?

[theotheragentm]

Can fish tell when another fish is sick? Can they tell when they have ichs before they are apparent to us with the physical white spot?

 

[jbarr]

One sign of ich other than the white spots is that they run into/rub on decorations.
Also another sign of general sickness is shimmying - You'll see your fish stay in one spot and shake it's head/tail very fast.

 

[Esra]

Those are ways we can tell if they are sick.

Not sure if other fish can detect it though.
I wouldn't think so.
Not much they could do if they did detect it anyway, can't really leave the room or anything.

 

[zenkatydid]

There's no possible we can find out, so this is purely theoretical.

But, I would say yes. In the wild, if an animal gets sick, it will do things to remedy it - eat something, or whatever. I would imagine fish are the same. I doubt they would think 'Oh, crap, I have ich again!" but they would not feel good. Things like flashing or shaking its head are responses to how it's feeling - so it does know that it is not well.

 

[turkey]

I have a fish that rubs himself on decorations and has been for awhile and has never shown signs of ick now i'm worried

 

[Pleco]

I have a fish that rubs himself on decorations and has been for awhile and has never shown signs of ick now i'm worried

It may just be trying to get food that is in the substrate. My bolivians do this at times, then i realized that they were moving the substrate to get at food.

-Pleco

 

[7Enigma]

I believe the answer is yes. Semi-aggressive tropical fish generally establish a pecking order both among species and other tankmates. When a more aggressive fish becomes ill, other fish will take advantage of this and establish dominance. I have seen several instances of increased aggression (nipping fins, aggressive posturing) when previously healthy fish become ill.

 

[coldmachineUK]

I believe the answer is yes. Semi-aggressive tropical fish generally establish a pecking order both among species and other tankmates. When a more aggressive fish becomes ill, other fish will take advantage of this and establish dominance. I have seen several instances of increased aggression (nipping fins, aggressive posturing) when previously healthy fish become ill.

I completely agree. In the more intelligent or social fish it tends to be that sick fish are considered weak and a burden to the group: they will either be killed by their own kind or abandoned. Cichlids are a good example of this: weaker individuals are generally bullied by everyone higher in the pecking order.