TPWD News Release — April 18, 2013
ATHENS—On December 4, 2004, Jerry Campos was fishing for largemouth bass on Falcon International Reservoir when he caught a 14.28-pound fish that became ShareLunker 370.
On April 13, 2013, Allen Lane Kruse of Nacogdoches caught a 12.54-pound bass from Lake Naconiche that has been submitted as a water-body and catch-and-release record for the new impoundment near Nacogdoches.
The connection? DNA testing revealed that ShareLunker 370, which spawned at the Texas Freshwater Fisheries Center (TFFC) in Athens, is the mother of the Lake Naconiche fish. If Campos had not entered his fish into the ShareLunker program, Kruse would not have had the opportunity to catch his fish, because it would not have existed.
“This is the perfect example of why the ShareLunker program was established,” said Allen Forshage, director of TFFC. “It’s called ShareLunker because the program gives anglers the opportunity to share their catch with others. Fingerlings from ShareLunkers that spawned have been stocked into more than 60 reservoirs across Texas.”
The father of the Lake Naconiche fish has deep roots in the ShareLunker program as well. Genetic data showed its mother is ShareLunker 305 (caught by Nathan Strickland from Lake Fork in 2000), and pedigree data showed its grandmother is ShareLunker 184 (caught by Richard Crow from Lake Fork in 1994), and its great-grandmother is ShareLunker 9 (caught by Troy Johnson from Gibbons Creek in 1988).
ShareLunker 370 produced 12,699 fingerlings, some of which were held at TFFC as possible future broodfish. The Kruse fish was one of 173 adult ShareLunker offspring that were released into Lake Naconiche in 2009 along with 95,389 ShareLunker fingerlings. The adult fish are now eight years old and are on the threshold of being old enough to attain the 13-pound size necessary to be entered into the Toyota ShareLunker program.
While the paternal lineage leading to the Kruse fish was composed solely of non-introgressed Florida largemouth bass, the maternal lineage was introgressed with northern largemouth bass alleles. Typically, ShareLunkers that are pure Florida largemouth bass are preferentially spawned in the ShareLunker program given their greater likelihood of reaching large sizes (more than 15 times as likely as a hybrid to reach 13 pounds); however, exceptions are made and this was the offspring of one of those exceptions.
“The reason the offspring of a non-introgressed ShareLunker are more likely to reach 13 pounds is because of the way genetic variation underlying quantitative phenotypes like size is transmitted to the offspring. The genetic components of size can be broken down into additive, epistatic and dominance effects. Hybrids are more likely to have unique epistatic and dominance configurations that contribute to their large size, but only the additive component is passed on to the offspring,” said Dijar Lutz-Carrillo, the TPWD geneticist who performed the DNA analysis. “You can see the results of this in our reservoirs. For instance, in Lake Fork less than 1 percent of the general population is made up of Florida largemouth bass, but that 1 percent of the population contributes 30 to 40 percent of the ShareLunkers that are caught there. The remaining 99 percent of the population (the hybrids) produce the rest.”
“Given that a certain portion of the population is much more likely to reach ShareLunker status, it makes sense to focus limited resources on those fish. Plus, wild populations will (and do) produce plenty of hybrids without our help,” noted Forshage.
“Fisheries are stochastic (random) systems; you can’t always predict the outcomes based on the inputs,” said Lutz-Carrillo. “But we use the best science available to make management decisions, and we are starting to see returns on those investments. We’ve greatly expanded our genetics database and increased the power of our molecular marker panels over the last few years, so I expect we will see more of this in the future.”
The catch is an indicator of something else as well: Lake Naconiche is poised to produce big bass for years to come.
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