Actually, they need oxygen. Fish die in ice-covered ponds
that do not have water flowing into them when they deplete the available oxygen. Plants under water can make oxygen when
sunlight shines through clear ice but deep snow makes it dark. A few years ago
we lost our large fish when we neglected to aerate our pond soon enough.
After the ice thawed, we gathered them up and planted them in the garden but
would have preferred to have them alive.
Many ponds in our neighborhood have this problem and support
only small fish, reptiles and amphibians. A few fish in a deep pond or any number of fish in a
pond with a babbling stream running into it can live under ice
until it melts. We feed the fish in our acre and a half pond so there are quite
a few larger ones that seem to need more oxygen than minnows and young ones. We
use a small air compressor that creates a stream of tiny bubbles (through air
stones) that pump warmer water from ten feet down up to melt a large hole in
the ice, see photo below.
Some winters here in upstate New York have had well spaced
thaws that periodically aerated the water so that we didn’t have to bubble the
pond but the last few winters have been quite cold for long periods that
required attention to keep our animals under the ice healthy.
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| Compressor and Air Stones Creating Open Water in 5 Inches of Ice Covering a Pond |
