July 09, 2009 12:00 am
—
By JIM AUSTIN
Cooperstown Crier
The ten-year-old Otsego
Lake walleye stocking program
is being called a continuing
success.
The program to re-establish
walleye in Otsego Lake
began in 2000. Since that
time, between 40,000 to
80,000 walleye have been
stocked each year, including
several thousand advanced
fingerlings in the
fall.
The walleye is a game
fish historically popular in
Otsego Lake.
But by the 1970s it had
disappeared due to the accidental
introduction of the
cisco, a fish which preys
heavily on walleye fry, in
the 1950s. In 1988, the alewife,
a non-native forage
fish, was illegally introduced
to the lake.
``Since the alewife is
highly effective at consuming
the microscopic aquatic
animals we call zooplankton,
they decimated the
larger plankton, which allowed
algae to go unchecked.
This situation led
to reduced water clarity
and, more significantly,
lower oxygen levels in deeper
waters,’’ said BFS director
Dr. Willard Harman.
The abundant and underutilized
alewife forage
base would provide the opportunity
for the introduction
of another predator
species like the walleye.
According to the plan,
walleye fry would be supplied
by the DEC from eggs
and milt collected from wild
fish in Oneida Lake. The
fry would then be given to
commercial growers to raise
them to two-inches in
length in ponds.
The fingerlings were
first released in Otsego
Lake in early July 2000 to
coincide with the spawning
of alewives.
The newly-hatched alewife
fry would provide excellent
food of the right size
for the walleye fingerlings,
Harman explained.
The walleye, it was believed,
would grow rapidly
on the plentiful alewife forage
and will help to increase
the quality and diversity
of fishing
opportunities.
After three years of the
stocking program, positive
results were being found
when gill netting was carried
out in 2002.
``We were astounded at
the numbers and size of the
walleye,’’ said Matt Albright,
Assistant to the Director
of the Biological
Field Station.
According to Albright,
not only were the walleye
unexpectedly long (16 to 19
inches), they were also fat,
and their stomachs were
full of alewife.
At the time, Harman
said that it is theoretically
possible for the introduction
of walleye to affect the
clarity of the lake by reducing
the population of the
alewives which eat the zooplankton
which feed on algae
whose numbers reduce
the clarity of the water.
``It’s possible, but nobody
involved thinks it will happen,’’
Harman said. ``The
DEC biologists think its an
extremely remote possibility.’’
It now appears the walleye
may have contributed
to near record clarity in the
lake’s water.
Albright said Tuesday
that recent measurements
show water clarity in the
lake reaching 10 meters, or
approximately 30 feet.
``I’ve never seen clarity
that high,’’ Albright said.
``It’s usually two to twoand-
a-half meters this time
of year.’’
He said the record stands
at 11 meters ``going back a
long way.’’
Albright said that the
clarity is also a result of the
growing zebra mussel population
in the lake and
that’s it’s difficult to determine
whether the walleye
or the zebra mussels played
the larger role.
Albright also noted that
large zooplankton numbers
are almost back to what
they were when the alewife
was introduced.
``The abundance of larger
zooplankton has increased
substantially, and
their mean size is larger,’’
Harman said.
The walleye have not established
a breeding population
in the lake, but Albright
said that was not
expected because the walleye
fry are subject to predation
also.
The stocking continued
this summer with another
40,000 fingerlings. The fingerlings
are released in water
about 15 feet deep over
weed beds where they can
hide to escape predators.
For 2009, the Otsego
County Conservation Association
dedicated $6,000 in
support of the walleye
stocking.
``Walleye stocking has
proven to be an effective
means of controlling the
alewife, an invasive aquatic
species which threatens the
ecological balance of Otsego
Lake,’’ said OCCA executive
director Erik Miller.
According to Miller, support
of the walleye stocking
program is consistent with
goals defined in the Plan
for the management of the
Otsego Lake Watershed,
approved by the towns of
Middlefield, Otsego, and
Springfield, and the Village
of Cooperstown in 1998.
OCCA also contributed
$2,000 to the initial stocking
effort.
Funding has also been
provided by the Gronewaldt
Foundation and the New
York State Department of
Environmental Conservation.
Little historic information
exists on the walleye in
Otsego Lake and it is not
known if they are a native
species. Records show that
walleyes were stocked in
the lake in 1913 with the
heaviest stocking occurring
between 1922 and 1934
when 4.15 million fry were
placed in the lake.
Cripple Creek historically
supported a major
spawning run of walleye
and in 1969 it took only a
few hours to capture and
tag 100 fish.
Reports from anglers in
the 1970s suggested a reduction
in the size of the
walleye spawning run in
the creek. In the late 1970s
fishermen were complaining
about declining catches
of walleye in the lake and
in 1990 netting of the creek
from March 31 to April 28
captured no walleye.
The decline of the walleye
in Otsego Lake is
blamed on the inadvertent
introduction of cisco by the
DEC when they were stocking
whitefish.
``The cisco simply gorged
themselves on walleye fry,’’
said Harman. ``Over time,
they whittled away at the
walleye population.’’
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