I have been helping my brother expand his fishpond. The fish have been targeted recently by a beautiful but deadly great blue heron. So we decided to expand the pond and incorporate lots of underwater ledges and hiding places to give the fish a fighting chance.
Jim's estimate of fish population before this pond excavation began was about 40 - 50 fish.
When we got down to transferring them into the wading pools in order to reline the expanded pond, we found no more than 10, with only two larger than 5" long!
That heron is a superbly engineered fishing entity!
So, days later, and many hours of back-breaking work, and all that remains is cosmetic - for next week.