Do fish hold grudges?

RoyC · May 18, 2020

I added a Yellowfin Flasher Wrasse after QT to my display tank. Initially the Blue/Green chromis chased it around for 2 days, then the rolls reversed and the flasher wrasse is now chasing the chromis every time it sees it. It ignores all the other fish in the tank. I thought this was meant to be a peaceful wrasse, so is it holding a grudge for it's treatment when first introduced. Is this even a Yellowfin Flasher Wrasse? Is it a juvenile that will settle down with age, or will I have to remove one or the other of them?

Cell · May 18, 2020

Can't really gauge the hierarchy when fish are first added. Once the new fish is comfortable, then you'll see the true pecking order.

Angel_Anthias lover · May 18, 2020

Thats not a flasher wrasse, it's actually a fairy wrasse, maybe @evolved knows what species it is

evolved · May 18, 2020

RoyC said:
Is this even a Yellowfin Flasher Wrasse? Is it a juvenile that will settle down with age, or will I have to remove one or the other of them?

No, this is Cirrhilabrus filamentosus - the most aggressive species of Cirrhilabrus - not a peaceful species by any means. It won't get better, but rather worse with age, I'm afraid.

RoyC · May 19, 2020

Thanks for the response @evolved, it looks like I was sent the wrong fish ordered off the internet. I will have to try and catch him and re-home him.

Katrina71 · May 19, 2020

Why are the pretty ones always naughty?

ca1ore · May 19, 2020

Don't anthropomorphize your fish LOL. Aggression is mostly a function of hierarchical dominance, which is why intra-species issues are most common, followed by similar body shape, color, etc. But, a dominant fish can pick on just about any other fish given the right circumstances. You may be able to 'reset' the dominance relationship by removing the aggressor for a while - I did this with a purple tang that was attacking a new gem. Grudges have nothing to do with it.

RoyC · May 19, 2020

ca1ore said:
Don't anthropomorphize your fish LOL. Aggression is mostly a function of hierarchical dominance, which is why intra-species issues are most common, followed by similar body shape, color, etc. But, a dominant fish can pick on just about any other fish given the right circumstances. You may be able to 'reset' the dominance relationship by removing the aggressor for a while - I did this with a purple tang that was attacking a new gem. Grudges have nothing to do with it.

Thanks, I might just try this if I can catch him.

SALTYMOPAR · May 19, 2020

I pretty sure this guy always holding a grudge

LordJoshaeus · May 19, 2020

Some animals do seem to hold grudges, but I have no clue if any fish can/do...fish are a lot more intelligent that they are often given credit, though (manta rays and cleaner wrasses, for example, can both recognize themselves in a mirror, strongly implying that they are self aware to some extent and thus more intelligent than many mammals and birds). Also, many fish species have been recording refusing to spawn with another fish of the opposite gender even though conditions are seemingly perfect, evidently because their temperaments were not compatible (this is why many freshwater fish - especially cichlids, which are infamous for this - are purchased in groups and allowed to 'pair off' rather than just being shoehorned with a random member of the opposite gender).