Get to know your local predators
You can learn a great deal about local predators by contacting your municipal animal control, or your county or state fish and game departments. If you are lucky to have a pond association in your area, members can be a valuable resource. All can advise you on the types of wildlife to watch for, and recommend safe techniques for protecting you and your property.
Minimize the opportunity for plunder
If you are about to build an additional pond, or expand the one you have, we recommend that you build it as large and deep as possible, and with steep sides. If you plan to have Koi, a depth of three to four feet is recommended. Also, because you can always elevate your plants with rocks, make plant shelves 12" to 16" deep so they won't be used as access points by predators.
Always locate your pond where you can observe it from a window, and have a light ready to illuminate it at the flip of a switch.
Deter the predators that pose the greatest threat
Netting - Covering your pond with netting, particularly at night, when predators are most active, is an excellent way to control most predators. Netting can also be used seasonally, for example, during spring and fall when animals are most active.
Alarms - Animal Away, a small electronic device, detects animals moving into its protected area, then emits a high pitched sound and flashing lights to send them fleeing. For nighttime control, you can install motion sensors to trigger your exterior or pond lighting system.
Fencing - Children are always curious about ponds. To prevent accidental injury and vandalism, we recommend you talk to your neighbors when installing a pond. Ask them to make sure their children do not enter your yard unsupervised. Keep your yard gate locked, and place a small caution sign on it. If you expect frequent visits from predators, you may need electric fencing immediately surrounding your pond. Electric fencing is easy to install and will deter most non-flying predators.
Decoys - Some predators like herons are territorial and will not intrude on an area they perceive as already dominated by one of their kind. Others simply won't risk attack from a natural rival like a snake or owl. These are all available as decoys and work very well. For optimum effect, they need to be moved about frequently so that predators don't catch on.
Repellents - Spray repellents use smell and taste to ward off predators like deer, squirrels, and raccoons. They are very versatile because they can be applied wherever you desire. For best results, they should be renewed at intervals or after rain.
Hiding places - Predators cannot eat your fish if they cannot catch them. Make sure your pond provides plenty of floating vegetation for your fish to hide under, and structure to dive below. Sections of wide diameter black PVC tubing can be placed inconspicuously on the bottom of your pond. These have the added advantage of providing good habitat for your fish. If you encounter an agile predator like an otter, consider a fish refuge, which is a hard mesh cage that allows fish in but keeps predators out.
Don't wait to experience a loss. Predator proof your pond today.