Grass Carp are easily the most elusive fish I have ever seen. I too had a pond overstocked with them and tried everything to catch them....to no avail. After they had cleaned the entire pond of all vegetation, they got so hungry I finally caught some on worms while bluegill fishing. They will break tackle if you manage to hook one....extremely strong fish. I tried shooting them with a .22 rifle like someone else mentioned. Only confirmed one kill....they have really hard heads. They do seemingly live forever, well over 20 years. Finally had to rotenone the pond and they were the last fish to die. They actually beached themselves to get oxygen and then flopped back into the water. It was an amazing acrobatic display. Be VERY conservative with your stocking rates for these fish.
