But they do not get within 20 feet of a heron. Check your local Petsmart. Call your local fish and wildlife office and sob over the phone. Sometimes you can get permission to sentence the bird to the great nest in the sky. They are a protected migratory bird.
Herons can wiggle under most nets.
The girls find them lacking in dignity and therefore do not recommend them. Take one large glass pickle jar. Eat all the pickles. Fill the bottom with aquarium gravel to a depth of several inches. Add a couple pretty marbles, agates or glass florist stones.