They are many ways to reduce the chances of your fish being eaten by Herons, are a just a few.
- Cover your pond with a fine mesh netting, while this may detract from the ponds natural beauty it probably is the most likely method to work.
- Purchase a plastic Heron. Herons are solitary birds and rarely fish close to each other, therefore a realistic Heron standing beside your pond should stop others visiting.
- Lay some lengths of drain pipe in your pond. While this will not stop predators catching your fish, it does give the fish somewhere to seek shelter.