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Lake Info
Normal Lake Level is 322.00 feet
above Mean Sea Level.
Current level for Cedar Creek Lake is:
321.60
Water Temperature:
81 degrees - top
77 degrees - bottom
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Florida strain stocking means
bigger Texas bass
Special to The Monitor
ATHENS–If shooting fish in a barrel is easy, showing why Texas bass are
bigger than ever is even easier.
Bigger bass are found in Texas today than 40 years ago because of three
words: Florida . Largemouth. Bass.
Texas Parks and Wildlife Department (TPWD) inland fisheries geneticist
Dijar Lutz-Carrillo has been using the latest technology to analyze DNA
from 147 bass weighing 13 pounds or more that have been entered into
TPWD’s ShareLunker program since 1995. (Samples were not available from
all the entries during that period.)
The largemouth bass native to Texas are commonly called northern
largemouth bass (Micropterus salmoides salmoides), and the Texas record
for this subspecies was caught in 1945. It weighed 13.5 pounds.
Florida largemouth bass (Micropterus salmoides floridanus) were
introduced into Texas public waters in the early 1970s by TPWD. This
species is known to attain weights greater than 20 pounds.
Soon the Texas record began to go up, and up and up. The current Texas
state largemouth bass record stands at 18.18 pounds and came from Lake
Fork in 1992.
Lutz-Carrillo found that of the 147 fish mentioned above, 76, or 52
percent, were pure Florida largemouth bass. Another 58, or 39 percent,
were crosses between Florida and northern bass, in which the Florida
influence was stronger. That’s 91 percent in which the Florida bass
genes dominated.
That’s no surprise, but is scientific confirmation of what TPWD inland
fisheries biologists have been saying for years: TPWD’s fish stocking
program works.
But there were some surprises in the data, too. Fish from Lake Fork,
which has been stocked only with Florida bass (no northern bass) since
its construction, produced 47 of the fish Lutz-Carrillo analyzed. Yet
only 30 percent of those fish were pure Florida. Another 53 percent had
more Florida than northern genes.
Four of the fish actually had more northern than Florida genes. Where
did the northern bass genes come from? Most likely there were northern
bass present in streams feeding the lake, and nature took its course.
One thing does come through loud and clear from the figures: Not one
single fish of the 147 was a pure northern largemouth, the native
species. The impact of stocking Florida bass on the genetic make-up of
the population couldn’t be more evident.
Even bigger bass may be in Texas anglers’ future. TPWD’s ShareLunker
program uses 13-pound or bigger bass donated by anglers in a selective
breeding program, stocking the resulting fingerlings into public waters.
Most are stocked as 1.5-inch fingerlings (some 78,000 in 2008), but a
portion are designated as Operation World Record (OWR) fish and are
reared to six inches before being stocked (more than 59,000 in 2008).
The growth of the OWR fish is being monitored and compared to growth
rates of wild fish by TPWD biologists.
Now in its fourth year, the program collected fish from Lake Raven, a
small lake in Huntsville State Park, which may give a hint of what may
lie ahead.
While the average four-year-old wild fish from Lake Raven weighed 2.23
pounds, the average OWR fish weighed 2.88 pounds. One of those OWR fish
was 23 inches long and weighed a whopping 7.23 pounds!
Allen Forshage, now director of the Texas Freshwater Fisheries Center in
Athens, where the ShareLunker and OWR programs are headquartered, was
one of the biologists who worked with the Florida bass introductions.
“The introduction of Florida largemouth bass and the implementation of
regulations that protect larger fish have had a profound impact on Texas
bass fishing,” Forshage said.
“The ShareLunker program has documented the catch of large fish, and has
provided the resources, such as funding for the DNA research and the
brood fish, to make fishing even better.”
Using the same DNA fingerprinting techniques portrayed in television
shows about forensics laboratories, Lutz-Carrillo can identify stocked
progeny of ShareLunkers. He can tell which fish were their parents, too.
While it sounds like magic, what’s really involved is many hours of
tedious laboratory work.
“Since January, 2004, tissue samples have been collected from every fish
entered into the ShareLunker program,” Lutz-Carrillo explained. “Prior
to that archival of the tissue was sporadic. The samples, preserved in
cryovials filled with ethanol, have been archived in a superfreezer at
minus 80 degrees C.
“Over the years, the methods for evaluating the taxonomic status of
lunkers has changed considerably,” Lutz-Carrillo added. “The ShareLunker
program was established in 1986, and until October, 2005, all the
entries were evaluated using one to three diagnostic genetic markers or
not at all.”
Later DNA testing was based on nucleic acids rather than amino acids.
“These new methods allow less invasive sampling techniques, easier
preservation methods and the analysis of a greater number of markers,
which gives more accurate results,” Lutz-Carrillo noted.
“In 2005, we optimized reactions to amplify six microsatellite loci in
largemouth bass,” he said. “Two of these were diagnostic for taxonomy.
Soon after, the National Institute of Health’s National Center for
Biotechnology posted 1,391 bases from the largemouth bass genome on
GenBank.
“In the middle of this sequence, the motif CA (for the bases cytosine
and adenine) was repeated 18 times in a tandem array – a classic
microsatellite,” Lutz-Carrillo said. “We quickly designed primers and
optimized methods for amplifying this repetitive sequence in our lab.”
Lutz-Carrillo now uses six diagnostic markers to classify every entry
into the ShareLunker program and eight polymorphic (highly variable)
markers to resolve parentage.
Some ShareLunkers are pure Florida and some are hybrids between Florida
and northern largemouth. Some hybrids’ genes are dominated by Florida
largemouth influence and some by northern.
Significantly, not one single ShareLunker analyzed to date has been a
pure northern largemouth. Lutz-Carrillo’s work confirms that the
introduction of Florida largemouth bass did indeed change the world of
Texas bass fishing.
According to an analysis of stocking history and bass size from 89 Texas
reservoirs conducted by TPWD Inland Fisheries biologist John Tibbs of
Waco, not all lakes are equal when it comes to taking advantage of
Florida bass genetics.
“In general, nutrient-poor reservoirs in South Texas had significantly
higher rates of Florida gene influence than nutrient-rich North Texas
reservoirs,” Tibbs said. “The size of bass that anglers caught seemed to
be influenced more by local reservoir conditions than by Florida genetic
influence.
“Anglers generally caught larger fish in large, shallow, young
reservoirs with a high incidence of Florida genetic influence,” Tibbs
noted. “Largemouth bass growth rates increased from west to east and as
elevation decreased.”
It seems clear that the most successful stocking policy will result from
putting Florida bass into reservoirs that offer the best conditions for
bass to express their genetic potential.
The downside is that not every lake will probably be a trophy bass lake.
The upside is that TPWD can make the most of anglers’ dollars by putting
them to work where they will do the most good.
 Sliding
in safely to second
Monitor Photo/Kerry Yancey
Mabank Sandlot Sluggers catcher Clay Conway (99) slides safely into
second base for a steal, as the cutoff throw gets away from Malakoff
Brewers second baseman Clayton Mattingly (13) during their Senior Midget
(10 and under) baseball contest at Mabank's George Watts Park May 21.
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