Have recently noticed in thje late afternoon, sneeking up on the 6000
gallon pond, that the Koi fish gather at the surface in a tight huddle
next to each other. These 25 fish range from 2 to about 10 years old.
It is almost a mystical sight. Of course when you walk up to the pond
and they see you, they scatter and go about their routines. Are they
communicating?

Any replies would be welcome.