IDNR biologists offer fish-restocking advice to pond owners
ponds and small lakes experience winter fish kills
Send a link to a friend
[April 03, 2014]
SPRINGFIELD — The Illinois
Department of Natural Resources Division of Fisheries is receiving
reports of fish kills on lakes and ponds around the state. Dead fish
have become apparent as ice cover thaws. IDNR biologists emphasize
that occasional fish kills are natural and occur when light cannot
penetrate ice, slowing the growth of algae and plants that produce
oxygen. It is often difficult to determine the full extent of a
winter fish kill since not all fish killed may be visible. As a
result, many pond owners are seeking additional information on the
cause, and advice on restocking after a winter fish kill.
are more likely to have been affected. Deeper ponds
initially have a greater volume of oxygen and are more
likely to sustain fish. But even some of these ponds are
experiencing winter kills.
have experienced winter fish kills in the past are likely to
have done so again this winter.
In many cases,
the last spawn of bluegill (up to 1 inch long) can survive
the low oxygen levels. Pond owners should assume all bass
have died and restock as soon as possible.
Even if some bass survive, it is
easier to correct an overpopulation of bass than an
overpopulation of bluegill.
IDNR county biologists can provide proper stocking advice for
your specific pond, especially if species are present other than
what is listed below.
General stocking guidelines for
the smallest fish available are as follows:
bass: 50 per acre
300 per acre
catfish: 40-100 per acre (optional)
minnows: about 5 pounds per acre.
bluegill (3 to 5 inches long) can be stocked in the fall if
the pond owner wants to wait to see if bluegill survived.
It is important to follow up in
spring 2015 with another 50 bass per acre, but the larger
size (5 to 7 inches long) should be stocked then.
[to top of second column]
If bass fry are
not observed in summer of 2015, it may be wise to stock another
50 per acre in spring 2016 — again, the larger size.
Redear sunfish may
not do well in northern Illinois, where pumpkinseed sunfish are
the ecological equivalent.
Grass carp should
only be restocked if vegetation was a problem previously.
Crappie or hybrid sunfish should not be restocked without
consulting your county fish biologist for suitability or timing
of the restocking.
Other species should only be stocked
under the direction of your county fisheries biologists. To find
the biologist in your area, visit:
Follow the IDNR on
Facebook and Twitter.