fishies

I am participating in an Art2Mail postcard swap. The deadline is March 15 and I am on time. These are the postcards that I am sending out. All fish. There's something about fish that appeals to me; I think it's their silence. They glide and flitter and dive and meander and, from our point of view, they do it quietly. Yes, often they are frantic, but that's when something disturbs them, like our human presence. But when there are no predators, then there is nothing to do but eat and enjoy the day.

I wonder: what kinds of sounds do fish make?