“Texas: On the Coast - The Redfish are Back”



Fly Rod & Reel
By Phil H. Shook

The specks and reds are back in numbers not seen in decades in shallow estuaries and channels and Gulf passes along the 370-mile Texas coast. An ambitious marine hatchery program-designed to supplement and enhance existing game fish stocks-is getting the credit for the resurgence, along with a ban on commercial netting, tighter size and bag limits and a string of mild winters.

A fishery that was struggling two decades ago and devastated by a killer freeze in 1989 has rebounded in quality and quanity. According to the Texas Parks and Wildlife Department, last year recreational anglers in the state took an estimated 230,000 red drum within the 20- to 28-inch legal size limit-77,000 more than in 1992. And Parks and Wildlife biologists say the average weight of redfish retained by Texas anglers has increased from about two pounds in 1977 to an incredible five pounds in 1992. Success rates for spotted seatrout-better known in Texas as "specks" or "speckled trout" are also climbing, and the average creeled fish has doubled in size since 1974, to 1.9 pounds.

Since Texas Parks and Wildlife, the Gulf Coast Conservation Association and Central Power and Light Co., teamed up in 1981 to build a hatchery in Corpus Christi, about 200 million redfish fry and fingerlings have been released in Texas bays. In 1993 the hatchery program produced 33.6 million red drum and 1.9 million spotted seatrout fingerlings that were released in the major Texas bay systems.

All of the fish are produced through natural spawning, using a photo-period/temperature maturation cycle of 150 days. "We don't do anything weird like use hormones or cut off the eyes like they do with shrimp," says Robert Vega, program leader for TPWD's marine fish hatcheries. By carefully regulating light and temperature, biologists are able to simulate a year of seasons in five-months. This creates two spawning sessions a year in tanks that hold two or three pairs of brood fish. Near the end of each cycle, the biologists simulate a spring cold front to induce egg-laying.

A number of safeguards protect the integrity of wild fish populations. To maintain a natural genetic balance, Vega says hatchery officials replace 25 percent of the 140 or so brood redfish they keep at the Corpus Christi hatchery every year. Vega says fish are constantly being collected and released up and down the Texas coast.

While research indicates that all the red drum in the Gulf of Mexico are part of one population, there is evidence of subgroups among spotted seatrout populations in different bay systems. Because of this, Vega says, the department takes care to return seatrout brood fish and all the eggs, fry and fingerlings produced from those breeders to their native bay systems.

While the seatrout program continues to grow, the high catch rates for redfish and their frequent appearances tailing on the flats or moving across the bays in large schools, have made the chunky fish with the black ocellus a favorite target fo the coastal angler.

"Texas now has the premier red drum fishery in the country," says Larry McEachron, science director of coastal fisheries for TPWD. McEachron says the goal of the hatchery program is enhancement, rather than replacement. He notes that most red drum mortality occurs during the annual migrations from the Gulf of Mexico into the bays through the major passes.

The stockings in the bays are intended to reduce the effects of that mortality and stabilize the highs and lows in recruitment. "In the good years, we will increase the numbers by some level," Mceachron says. "In the bad years, years in which we have had low recruitment, we have actually put in fish that would not be there."

With the understanding that environmental factors can significantly alter the situation at any time, the goal now is to maintain the fishery at or slightly below the current level, according to McEachron. "We hope we can stabilize it so we can have good fishing routinely without the highs and lows," McEachron says. "That's what we are really shooting for."

With more than a decade of experience with red drum, there is enough data to do a virtual population analysis, says Bob Colura, TWPD fisheries biologist at the Perry R. Bass Marine Fisheries Research Station near Palacios. "Now we can go in and say 'This is the population,' and start projecting what the population will be next year. We can make a regulation change and be able to say 'This is what it would do to the fishery'."

TPWD also has a number of studies under way to measure the success of the stocking program. Evidence from bag-seine sampling on the upper Laguna Madre indicates that 20 percent of the fish in the bay system are hatchery-reared. The sampling tracks out-of-phase stockings-those fish released during spring and early summer, when young are generally not present.

McEachron says TPWD chose the upper Laguna Madre, a shallow estuary starting just below Corpus Christi, for the project because it is the only bay system on the coast that doesn't have direct access to a pass.

"My assumptions are that if these fish we are catching out of phase in the Upper Laguna-have the same mortality through time, then ultimately 20 percent of the fish in the sport creel would be stocked fish."

Another project, designed to back up the findings of the out-of-phase sampling and to provide more data on the survival rates of hatchery-raised fish, will involve the stocking of genetically-marked fingerlings. TPWD biologists have spawned a group of red drum that has what they describe as a rare allele, or gene, that appears in only seven percent of the red drum population.

East Matagorda Bay, a small bay system below Galveston, will be the field laboratory for the project. Twenty-five percent of the stocked fingerlings will have the gene. The biologists will then take samples from East Matagorda to see if the ratio goes up significantly. If it does, it would provide additional evidence that the stockings are having an impact on the redfish population.

"We hope that these stockers will increase the ratio in the catch of the sports fisherman," McEachron says. He says positive data from the out-of-phase stocking and genetically tagged fish would nail down evidence on survival rates. "We could say-the sportsmen are catching them at this level, it is working and we are getting the fish back."

TPWD biologists are aware of the controversy surroundng selective breeding programs, and McEachron says tight controls are in place. The chose East Matagorda Bay for the one-time-only experiment because it is a very small system. Whatever the number of selectively spawned fish that do escape into the Gulf spawning populationwould be diluted out, with a negligible impact on the overall redfish population, McEachron says. "We are not looking at a long-term stocking for that fish. If we see a problem, we shut it down and it does not affect the entire coast." According to McEachron, the department will stock the selectively bred fish only as long as it takes for them to turn up in creel surveys.

Another experiment designed to determine how well the stocked fish are integrated with the wild population involved marking a million fingerlings with oxytetracycline-a chemical that stains the ear stone. The fish were released in the Upper Laguna Madre, where they will be tracked over the next several years.

And, in a separate project, biologists are using what is called the Optical Pattern Recognition System (OPRS) to examine scales to distinguish hatchery-reared fingerlings from wild fish. Vega says the test is based on the theory that, because of an abundant and constant food source, fingerlings in hatchery rearing ponds lay down more consistent and identifiable rings on their scales than do wild fish.

While biologists work on ways to precisely measure the impact of the stocked fingerlings in Texas bays, the state continues to expand its marine hatchery program. A new hatchery in Lake Jackson, on a site donated by Dow Chemical, is scheduled for completion this summer. The $11 million facility will have an annual production capacity of 20 million fingerlings.

In Texas, where a conservation ethic has grown with the membership in organizations like the Gulf Coast Conservation Association, anglers are not taking the redfish bonanza for granted. "Don't mess with success" was the outcry from many anglers and flats guides last year, when TPWD floated a proposal to increase the daily bag limit for redfish from three to four. The proposal was dropped, and the old bag limit remains. And so do the redfish.

April 1994