By Faith Peppers
University of
Georgia

Herons can gobble up fish from backyard ponds almost anywhere,
any time.

The problem is at its peak in spring and early summer, when the
herons feed their young, says David Pool, a koi expert with
Tetra Pond, a water-gardening-products company in Blacksburg,
Va.

Each day, Pool says, an adult heron needs about 13 ounces of
food, or about three 6-inch koi or 10 2-inch goldfish. Herons
take twice this amount when feeding their young.

They’re generally shy birds, he says, and visit garden ponds
when everything is quiet, usually early in the morning or in
the evening.

Once the herons have found an easy source of food, such as
colorful fish in a shallow pond, they’ll return until they’ve
taken most of the fish.

To keep feathered fish burglars out of your koi pond, Pool
offers these tips:

Netting. Suspending a net 6 to 12 inches above the pond
surface will prevent the heron from attacking your fish. Make
sure the net is taut and can’t fall into the pond if the heron
tries to land on it and spear the fish through it. This may not
be the best-looking solution. But it’s by far the most
effective.

Perimeter Wire. Herons don’t normally land directly in
the pond, as they will scare the fish. Instead, they land in
the garden and stalk toward the water. Suspend strong fishing
line 12 to 18 inches above the ground around the pond to stop
the heron from reaching its destination. Put the fishing line 6
to 12 inches back from the pond to prevent the heron leaning
over the barrier to catch the fish.

Heron Scarers. A number of commercial scarers work in
different ways. Some use a trip wire and produce a loud noise
and, in some cases, a visual deterrent to scare the heron away.
Some use sound inaudible to human ears. Others detect the heron
with infrared light and scare it away by spraying a high-
pressure jet of water. Remember, these can also be activated by
guests visiting your yard.

Plastic Herons. These are popular. Their success is
based on the principle that herons are territorial and won’t
feed close to another heron. Unfortunately, this isn’t
completely effective anytime, especially in late winter and
early spring when herons search for a mate. Then it may
actually attract herons to your pond.

Pond Design. When designing your pond, it’s possible to
make life tough for herons. Dense growths of tall plants or
shrubs around the pond will limit their access to the water.
Making the pond side steep and the water 8 to 12 inches below
the edge of the pond will also help, because the heron won’t be
able to reach the fish.

If you do lose some fish, don’t resort to harming or killing
the herons. They’re protected species.