Barnacle blenny behavior

[saltyhog]

I have 3 Panamic barnacle blennies in my nano tank (25 gallon IM Lagoon). One of them (the largest) has started an unusual behavior in the last few days. The front 1/2 of his body is now extremely dark, almost black. None of the spots are visible on that half. The front portion of his dorsal fin is now very bright orange. He also is bobbing up out of his barnacle and back down rapidly. Dominance behavior?

@eatbreakfast I know you've kept these guys before, ever seen this?

 

[Jaebster]

Love these blennies.... interested to know too.

 

[lebreef]

I have three as well! I have yet to see the color change you mention. Very personable fish, aren’t they!

 

[saltyhog]

He's being a little shy tonight but I'll try to get a better picture. The color change does come and go. You can see in the picture the normal color of the one nearer and the one with the color change in the background.

 

[VKP01]

I’ve got a couple, one keeps the light color and one keeps the dark like in your picture. My darker one also bobs, I’m not sure if the lighter one does. When I got them they were both dark and one gradually became lighter. My darker one is definitely the dominant one, it would make sense that it’s an a dominance thing.

 

[lebreef]

Interesting! I’ll keep it in mind to notice behavior if color changes. I’ve got 2 using the same rock as a borrow and the third a coral.

 

[eatbreakfast]

Sounds like a nuptial display to me with the color change and bobbing.