Some Kind Of Perch?

[sashkello]

Location: Shelly Beach, Sydney, Australia (saltwater, bay)
Depth: ~2m
Size: ~25cm

Saw this one a few times before, but this time noticed something I haven't paid attention previously. It changes its apparent color using fins/scales. Shot a video, and extracted some photos...

Here's how it looks at the start, kind of a military camouflage:

And then it slowly calms down and color gets almost solid, greenish:

Is it something many fishes do and I simply haven't noticed before? What species is this one? At first I thought it's just a rock cod, but those guys don't seem to ever have such a split tail.

 

[Steve_C]

Don't know about your fish but a number of fish can change their color or patterns depending on what they are doing or feeling. Blue tang for instance have a range of color they can go through. Some can change quickly.

 

[Kharon]

Yep. Especially the filefishes, cowfishes, flounder - they can/do change in a matter of seconds. Sergent major males get very dark when guarding a nest of eggs and turn back once the eggs are hatched.

 

[sashkello]

Wow, that's interesting, I'll keep an eye out for this stuff!

FYI: the interval between these photos is about 15 seconds.

 

[tarponchik]

Also trumpetfish. This is likely the same guy cause I took both shots at the same coral head, one day difference.