Pond life includes having Koi and gold fish, or even frogs in your pond.
Sooner rather than later, predators will visit and do their best to make a meal of your fish.
Herons, and raccoons are the most prevalent predators, with Kingfisher, Mink, Egret, Hawks, Owls, and snakes following close behind.
Natural deterrents include providing a place for your fish to hide in fall and winter, when natural foliage is at a minimum. Placing a net over the pond, PVC pipe, or terra cotta pots lying on their sides in the water will all help your fish stay healthy. Motion sensor sprinklers are another natural way to keep garden pond predators out of your pond, but will not usually deter "flying fisher-birds". In short, if you decide to keep fish alongside the wildlife that will visit your pond, you will have to take steps to make sure that your fish survive throughout the year.
Always remember that when you build a pond, the wildlife will come because you have created a sanctuary in your backyard.
The Great Blue Heron, part of the Ardeidae family is found in most of North and Central America, The West Indies and Galapagos Islands where there is water. Heron need water in order to feed.
The Great Blue is the largest North American heron, weighing between 4 and 8 pounds. It is white faced with a pair of black plumes situated just above the eyes and running to the back of the head. The bill is a dull yellow, becoming orange during the mating season.
To keep the heron from becoming a part of pond life you can employ the use of decoys, because Heron are territorial and won't feed in another Heron's 'bowl' but Heron are very smart and will figure out eventually that your decoy is fake. You can move the decoy around to keep the bird confused, but sooner or later, it will swoop down and make a meal of your prized fish in site of sharing" the territory. Keep one thought in mind when trying to deter the blue Heron: they are a protected bird; therefore do not set out to harm them.
Raccoons, known as Northern Raccoon, Common Raccoon, Coon or Washer Bear are native to North America but have been seen in the European mainland and Caucasus after escaping from fur farms.
They live together in small groups in forest habitats. Due to their adaptability raccoons are now being found in cities where they are becoming pests.
Raccoons get as large as 35 pounds, with the smallest found in Southern Florida. They have a characteristic black facial marking around the eyes, a blend of gray, brown and black fur and rare ones can be albino.
Being omnivorous, raccoons devour fruit, chickens, small mammals, but also will fish if near water, thus your Koi fish pond will become a convenient dining spot.
If your area is prone to raccoons, don't attract this form of pond life by placing shelves, or ledges that create shallow areas in the pond. The raccoon will fish from these at night because they are nocturnal mammals. In the morning you will have a pond without fish.