Tagging Ling

Cobia (ling) just keep getting more scarce, with popular tournaments recently cancelled along the Florida Panhandle, where these fish used to school along the beach and were caught by the hundreds from surf piers. One Galveston charterboat related that 15 or 20 years ago, he was logging 200 or more ling per year. In recent years, it’s been 15 or 20 fish. That’s a decline of 90 percent.

Texas is more of a frontier with more offshore habitat and choppy seas even during early summer’s fishing season. However, offshore fishing effort has declined here too, along with the oil rigs and shrimpboats that once attracted these fish. Maybe less fishing pressure will aid in recovery of the Western Gulf’s population of ling.

“There is a saying that Florida has all of the fishing pressure and none of the fish, and we have all of the fish and none of the effort,” says Matt Streich, assistant director and senior research scientist at the Sportfish Center, run by the Harte Research Institute for Gulf of Mexico Studies at Texas A&M’s campus in Corpus Christi.

Several cobia studies are now being conducted by Streich and colleagues. In addition to more expensive satellite tracking tags, they’re also using the reliable shoulder dart tags like we used in the late 1980s, that program also run out of Corpus Christi by Steve Qualia. Back then ling were more common, and his volunteers tagged 2,500 Texas ling. Today, because of scarcity, getting tags in these fish is more of a challenge.

(I tagged 105 ling for Qualia from my boat in 1987 alone. Later in 2002 in my Cobia Bible book, we listed 36 recaptures of Texas fish and a bunch from the Gulf Coast Research Lab in Mississippi.)

As Streich explains: “We tagged 25 cobia with satellite tags, tracking their movements. Mostly we’re seeing over-wintering offshore, they didn’t migrate to Mexico [and warmer climate]. I know some shoulder dart fish were recaptured down in Mexico years ago, but our recent fish didn’t have that long distance movement south. We programmed our tags to pop off from December-February, thinking they would be further south, but they mostly came up between Port Mansfield and the border. Out in 150-200 feet of water. That was pretty surprising.”

“Once the tag pops off, it floats and is recovered. It’s recorded the track of where that fish traveled. Of those tags, only one fish was just south of the border. Our sample was small. I know you guys tagged a lot of those fish in the 1980s with Steve Qualia, but it looks like only four were recaptured in Mexico. Texas cobia can go to Mexico, but seldom do,” said Streich.

What if one of these tagged ling is caught?

“We would like anglers to release the fish, so the tag can let us know where they've moved,” says Streich. “We would also like them to report the recapture to us on our website (http://www.sportfishcenter.org/) or call us at (361) 825-2525. We would need a tag number from either the satellite tag or the dart tag they will also have, date of recapture, and location (coordinates preferred). Length is also nice, but not required.”

The satellite tags are big, which is why no ling under 33 inches were utilized. They are painted black, presumably so as not to attract hits from other fish.

On the upper Texas coast, I never saw ling offshore during winter when fishing aboard the partyboats. Of course we were fishing in only 70-90 feet of water. The latest ling I ever caught during the year was a 40-pounder caught on opening day of duck season. After that, they vanished until April. Maybe they were migrating down the coast and stayed deep.

“Maybe” is pretty thin soup, however. Streich’s research will provide a more accurate picture. The satellite pop-up tags are recovered and downloaded, tracking everywhere that fish moved during a few months of travel. “The deepest we record our cobia was at a depth of about 300 feet,” Streich says. “I’ve seen one account of a ling swimming [beyond the continental shelf] in 4,000 foot depths, presumably on the surface.”

(I haven’t heard any tales from longliners who target bottom grouper out in 400-800 foot depths, but the water that deep is very cold and ling would probably avoid it.)

“Another thing we did was tag 25 ling with acoustic transmitters,” he said. “We have receivers near the inlets, in case they approach the jetties. Our colleagues at Texas A&M in Galveston have a bunch of receivers there, and offshore to the Flower Gardens. They didn’t detect any of our Aransas ling up there in two years. So, it’s almost like we have smaller groups of these fish, more residential. I’m curious if there is a resident group of these fish, and then a migratory group---different strategies in a population. Like with flounder; there was a study that showed 30 percent never migrated offshore during autumn. Ling may be the same, they just go offshore and stay deep during winter [and then return inshore next year.]

Streich’s next project involves tagging 50 more cobia with satellite tags that will, among other things, focus on whether the fish lives or dies. They carry a light sensor that can tell if the fish is inside a shark. [Very dark in there.] It hasn’t really been estimated but the stock assessment goes by a five percent mortality rate for these fish that are released after being caught. Which seems low, because people sometimes gaff and release fish when they measure too small. [Or they don’t use a landing net. Or the fish beats itself up while on deck]. That five percent estimate is based on what the fish looks like when released, not what actually happens to them. These tags should let us know,” says Streich.

As with many things in nature, the cobia population is more complicated than earlier thought. In the Carolinas, they even have an inshore stock that spawns in the bays, versus an offshore stock. With different genetics. Mississippi’s tagged fish wander the Eastern Gulf from Louisiana to the Florida Keys. Texas and West Louisiana obviously share fish at Sabine Pass that perhaps migrate further down the Texas coast. South Texas ling from Aransas to South Padre might be a separate stock that mostly refrains from visiting Mexico. Much work lies ahead, before details of the ling population can be ironed out.

Streich and his crew will be tagging ling this summer, and they’re looking for volunteers with boats to help, using the easy shoulder darts when they catch these fish. “We’ll send them four or five shoulder dart tags and the information card to fill out for each fish, says Streich. “We'll contact them and send a tagging kit. If they use them up, we’ll send more.”

Here’s a link where volunteers can apply at: https://bit.ly/43CIEPk.