it is illegal to shoot a blue.They where once on the endangered list .
Check your stats on the blue heron. The Great Blue Heron is not listed under the Federal Endangered Species Act of 1973. This species is protected in the U.S., Canada, and Mexico by the Federal Migratory Bird Treaty Act (MBTA) of 1918
Key word is "was".I know they are not now.
"The great blue heron is the most widely distributed heron in North America. It is so plentiful that it is listed as a species of least concern by the International Union of Conservation and Nature."If a a predator is eating your livestock or agriculture, and there is no viable way to stop it after repeated attempts, deadly force can be used.....they get shot.