Hi Everyone,

I have two oscars, one is larger than the other. The smaller tiger oscar is shaking the caudal fin at the larger one. I have had oscars before so I am not inexpierenced. I have had Oscars, and Convicts mostly but I also have had experience with Blood Parrots. I am just wondering what this behavior means to them. Because I am dealing with a larger oscar that has been getting somewhat aggressive to the smaller oscar. I am not sure if the smaller oscar is instigating it. Please any information is great.

Hey there.

It is an interesting behaviour. Some people have observed it right before breeding begins. Some people have noticed it during signs of aggressions. Some people have theorized it is a form of communication between the two cichlids. Some people dunno what is going on.

I have noticed my larger oscar doing it just recently. She seems to do it to say 'Hey look at me.' It has never been coupled by aggression.

I know this doesn't directly answer your question. It seems to show up at different times, and it certainly gets our attention doesn't it?!?!

This is common oscar behaviour, they do it to each other and to other fish. There doesnt seem to be any definitative reason which is why some say its a for of communication

If you have a female/male it could be a mating ritual, however if you have 2 same sex oscars I think it is the smaller oscar 'displaying' a bit in order to establish his own territorial boundary and 'standing up for himself,' i.e. communicating 'I AIN'T no jive turkey, don't mess with me, sucka'

How large is the tank?