|
STRIPED BASS COEXISTING WELL WITH CRAPPIE ON WEISS LAKE
CENTRE, Ala.__--In the early 1990s, anglers fishing for crappie on Cherokee
County's Weiss Lake noticed a decline in their catches and began to
suspect that striped bass, which had been introduced into southern waterways,
were eating crappie. Research conducted through the Alabama Department
of Conservation and Natural Resources (ADCNR) and Auburn University
has shown that striped bass are not feasting on crappie and may even
be expanding fishing options on Weiss Lake.
"Crappie is the major sport fish in Weiss Lake and a lot of the
county's income relies on crappie," explained Mike Maceina, professor
of fisheries and allied aquacultures at Auburn who has been helping
clarify the controversy. In the early 1990s anglers were catching fewer
crappie and more young striped bass. "There were concerns that
the crappie fishery would crash if the striped bass were eating crappie
or possibly eating enough shad to compete with the crappie," he
added. Shad, which are abundant in Weiss Lake and other Alabama waterways,
are a favorite meal of both stripes and crappie.
For the past eight years Maceina has been examining crappie reproduction
on Weiss Lake. He has found that lower angler catches in the early 1990s
were caused by poor crappie reproduction in the late 1980s due to drought
and lower lake levels. Ample production of young crappie occurred in
1990, 1993, 1994 and 1996 and crappie fishing is now thriving again
at Weiss Lake, as is fishing for largemouth bass and stripes.
Despite these findings, concern has lingered about the impact striped
bass may have on native fish populations.
According to Steve Smith, a district biologist with ADCNR, game and
fish authorities in several southern states began stocking striped bass,
a long-lived saltwater fish that can grow to more than 40 pounds in
size, in the 1970s to offer anglers the opportunity to catch a trophy-sized
fish.
"Alabama last stocked stripes in Weiss Lake in 1986 and only stocked
them five times over a 14-year period (1972-86)," said Smith. "Georgia
began stocking stripes in Allatoona and Carters reservoirs in 1972 and
1991, respectively. They have continued to stock stripe fingerlings
on an annual basis in both lakes, each of which is about 100 miles upstream
from Weiss Lake and part of the Coosa River system.
The stockings involved two different strains of striped bass - an Atlantic
and a Gulf strain. Initially, natural resource officials believed the
fish they were stocking would not reproduce in southern waterways because
striped bass eggs require specific environmental conditions to hatch.
"Striped bass eggs require 36 to 48 hours of free-flowing water
to hatch and they only spawn in March and April," said Maceina.
For many years, officials were correct. Mother Nature, however, changed
the conditions. After those dry years in the late 1980s that caused
water levels in Alabama's lakes and streams to drop, the early 1990s
brought abundant rainfall. "Apparently, in the early 1990s, conditions
were ideal in the upper Coosa River system in Georgia to allow striped
bass eggs to hatch," said Maceina.
Responding to concerns about the proliferation of stripes in Weiss Lake,
ADCNR officials began sampling young-of-the-year stripes in the lake
during 1994. Before sampling began, there was some speculation that
Weiss Lake was receiving escaped fish that had been stocked in Allatoona
and Carters reservoirs during previous years. With the help of Auburn
University and the
Alabama Agricultural Experiment Station, genetic testing was done on
captured stripes to find out which strain was reproducing or if they
had escaped from either of the two reservoirs upriver (Georgia had changed
from stocking Atlantic-strain fish in 1992 to stocking Gulf-strain fish
in 1993 and 1994). DNA tests revealed the stripes were of the Atlantic
strain, confirming that natural reproduction within that strain was
occurring somewhere in the waterway system.
Biologists also examined the stripes' eating habits. Maceina helped
identify the prey items in captured striped bass and found that crappie
are rarely eaten by stripes. So far, some 440 stripes have been sampled
from Weiss Lake, and of the 2,500 total prey items found in the stripes'
stomachs, only six were crappie.
"Those six crappie constitute a tiny fraction of the total prey
items found in the fish we sampled," said Smith. He noted that
94 percent of the prey found in the stomachs of the stripes was shad.
"Striped bass are not eating crappie," stated Maceina, "they
are eating shad."
Smith noted that big fish commonly eat smaller fish (in fact larger
crappie will even eat smaller crappie, but they prefer shad). Though
crappie and stripes both compete for shad, there appears to be plenty
of shad to go around.
While these results are helping calm the waters of controversy around
Weiss Lake, it also has confirmed that the Atlantic-strain stripes are
migrating down the Coosa River system into reservoirs that have been
historically stocked with Gulf-strain fish.
Both Smith and Maceina agreed that the stripes may benefit Alabama's
recreational fishing industry. "I think people should be happy
because it gives anglers another fish to catch," said Maceina.
Sure enough, anglers on Weiss Lake are gearing up with heavier tackle
to land the stripes, perhaps creating additional fishing options for
Weiss Lake and other fisheries in Alabama.
-30-
Katie Smith
1/5/98
|
