A garden pond is an attractive feature in the landscape, but including some fish in the water makes it even more so. While aquatic plants are most unlikely to be attacked by predators the same cannot be said for your fish. Herons are expert fishermen as are several other critters and there is nothing more heartbreaking than to find that you fish have disappeared over night. Fortunately there are steps you can take to protect your fish as Bonnie Grant explains in her article which I found on Dave’s Garden website.

Water features in the landscape offer a serene vista and soothing sound and motion. Installing fish into the pond further accents this lively feature. But what if you live in an area frequented by herons, racoons and other nighttime fish lovers? You don’t necessarily have to accept fish losses every season. There are many things to try to minimize loss and protect your fish.
Fish in the home pond or water feature liven up the environment and are peaceful denizens of the water to feed and admire. Unfortunately, most pond fish are defenseless and prey to numerous crafty predators. Racoons and herons are the most common bandits. These animals are on the look out for easy game at any time of the day or night. Pond fish can be quite expensive and many of us get very attached to our fish so losses can be both a hit on the wallet and on the heart. Luckily most humans are smarter than these pests and can find a way to stop their thieving ways.
Pond construction and fish installation considerations should be at the forefront of ones mine during construction. Herons do not fish in deep water. Construct a pond that is at least 24 to inches deep. At construction it is a good idea to provide caves and hiding spots. You can do this with large rocks and overhanging edges. You can also simply tip over a bucket at the bottom of the pond and line it with rocks to keep it down. Camouflage the bucket with more rocks and some lower plantings. Some pond builders also install some sort of cover at the center. Install an aerator. This will not only add oxygen to the water creating a healthy environment for plants and fish but helps to obscure the water surface and the fish below.

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