Recently I discovered a wierd behavior (wierd to me atleast). I'm not an expert to begin with.
I have 4 cardinals (dunno who's male//female)
But they are like bullying eachother, or is that just playing (maybe love? xD)
Fighting with their head.
Sometimes they just smash into the window with their heads constantly near the filter. for the stream of water??
Main question: bullying / windowing xD
anyone seen that ?