Essential Alligator Gar Research Underway in Oklahoma

By Craig Springer, USFWS

Lake Texoma lies over the Texas – Oklahoma state line. This boundary water is enormous. Denison Dam backs up the Red and Washita rivers for miles. The swollen arms of several tributary streams form massive lake coves that shoulder into the main water body. Consequently, there is much open water and ample shoreline for anglers seeking to catch black basses, crappie, sunfish, blue catfish and white bass.

The striped bass fishery is of good repute. And there is something to say for the alligator gar fishery as well:  alligator gar are under-studied.

For anyone with even a perfunctory knowledge of alligator gar, this may seem counter-intuitive—that not a great deal is known about one of the largest freshwater fishes in North America.

Consider this. Alligator gar reach an enormous 13 feet long and fatten to a plump 300 pounds. It’s a long-lived leviathan with some of the eldest individuals swimming this very moment, having hatched when Apollo 10 navigated around the Moon in May of 1969.

An alligator gar leaps alongside ODWC research boat in Lake Texoma. Photo: ODWC

These giant fish have a growing, almost cult-like following of anglers, and for good reason.  Hook one and hang on. An eight-foot-long alligator gar can take you for a ride. You will see a tail dance in a glistening spray of water akin to a silvery tarpon over turquoise flats in nearshore salt water—except alligator gar potentially have more heft. Get a gator gar to the boat, and with a parting flick of its round tail fin, its sinuous form slips into the murk to be caught again.   

Or will it?

That’s a question that Oklahoma Department of Wildlife Conservation (ODWC) research biologist, Richard Snow, seeks to answer.

“Virtually any information we glean from ongoing research is new information,” said Snow from his Norman, Oklahoma, office.  Snow is seven years into research into the alligator gar’s life history and has most recently embarked to learn more on a how the fish fairs after being caught and released.  The answer to this question is central to sport fishery management and has applicability well beyond the bounds of the Oklahoma state line.

The U.S. Fish and Wildlife Service’s Wildlife and Sport Fish Restoration Program funds Snow’s research—the monies derived from excise taxes paid by tackle manufacturersand then apportioned to state wildlife agencies for essential conservation work such as his.

Snow, an Oklahoma native, has had a years-long personal and professional interest in the fish. He has long enjoyed fishing for alligator gar. He earned a graduate degree at Oklahoma State University in natural resource ecology and management where he researched how to age the fish through its ear bones. The bones, called otoliths, lay down rings much like the cross section of a tree.

Snow says he also earned something else in graduate school. “I have a greater respect for the species—they’re a primitive fish, a swimming fossil that survive from long ago,” said Snow. “They are a remarkable fish—heavily armored on the outside like a tank because their insides are sensitive.” 

Now, as an ODWC research biologist, Snow has waded deeper into questions associated with catch-and-release mortality, food preference studies, and growth rates.

Richard Snow (ODWC biologist) and a subject of his ongoing research. The Wildlife and Sport Fish Restoration Program funds gar research via excises taxes paid by fishing tackle manufacturers. Photo: ODWC

Snow set up a hooking study with hefty captive alligator gar held in large ponds at Tishomingo National Fish Hatchery. He catches alligator gar just as anglers do at Lake Texoma and elsewhere, fishing with carp or buffalo fish heads. In the experiments, Snow allows gar to run with bait, played for 30 minutes and brought ashore, examined for noticeable internal injuries such as bleeding or air loss from the vent. The controlled environment allows him to monitor the wellbeing of the fish over a long period to detect effects of hooking that would not otherwise be noted in wild fish. The work is ongoing and results yet to be determined.

Along about May of the year, mature alligator gar move into shallow weedy coves of Lake Texoma and broadcast their eggs that adhere to vegetation. That act is replicated in tanks at the national fish hatchery where he and hatchery staff monitor the young gar.

“Alligator gar have explosive growth in their first year of life,” said Snow. “In the span of only nine days, they go from egg to a larvae with a sucker-disc on its head, and then to a predator. They pack on weight and by the end of the first growing season they’re a foot and half long.”

Alligator gar eat other fish.  In examining stomach contents of adult gar, Snow determined that sport fish species make up very little of the diet. Their common foods include common carp, river carpsucker, buffalo species, gizzard shad and white bass. 

Be not afraid– unless you’re a river carpsucker. Alligator gar feed on rough fish. Photo: Richard Snow ODWC

“These predators typically ambush their prey, but they also actively forage or scavenge their food,” said Snow. “In the heat of the summer when oxygen is low, they gulp air into a highly vascularized swim bladder to ‘breathe.’ Bowfishers and anglers take advantage of these habits to locate alligator gar.”

Snow says the ongoing research will help his agency steer alligator gar fisheries toward sustainability.

Cliff Schleusner, Chief of the Wildlife and Sport Fish Restoration Program, Southwest Region agrees. “These Holocene hold-overs have been understudied and the angler-funded work underway by the Oklahoma Department of Wildlife Conservation adds to a woefully scant body of knowledge,” said Schleusner. “Alligator gar, an apex predator, provide an ecological balance that regulate the populations of other fish species—not to mention an angling experience unequaled.”

–Craig Springer, External Affairs, U.S. Fish and Wildlife Service – Southwest Region

One Comment Add yours

  1. I have an ongoing 50 year admiration for the alligator gar, as a kid we floated the red river in flat bottom boats at night with Coleman lanterns hanging off front gigging fish, every trip was in full anticipation of at least seeing a big gar, most trips resulted in plenty of needle nose encounters and very few gator gar sightings, as a result of my fascination with this prehistoric fish I now would like to see severe conservation measures taken to insure that they’re numbers are kept at sustainable level, the fish shooting folks are really the only way of preserving this species through education to the ones that are responsible for they’re demise, my motto to these folks is if seeing one excites you then help preserve them because at the rate they’re being killed its a matter of time till you won’t see them at all, I live on Red river at savoy texas and would like to have an opportunity to in some way promote the well being of this species, I have an idea that might help educate the bow fishermen who for the most part are new to they’re sport and I don’t think they understand how fragile the existence of this species is. I recently was sharing evenings with a large gar I guessed at 50-60 lbs at our boat ramp every evening for 3 weeks then he or she disappeared after 4 days I found the fish 1/2 mile down from ramp washed up dead on bank shot dead center in back, Im sure its life was given for a picture with a shooter, kinda sad, if speaking to me on this project interests anyone let me know, if not pass my response along to someone it might interest if you have an opportunity, I will say my interest in this project is not self serving, I will prefer to stay out of any lime light that might shine my way, I am a business man and there will be haters out there that will not agree with the conservation goals that should be implemented.

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