Once a nuisance, alligator gar increasingly protected
Updated 10:56 pm, Wednesday, March 19, 2014
When the Trinity River, swollen from heavy spring rains, oozed over its banks along its lower reaches and spread over the adjacent landscape, as it almost annually did back when I was a teenager, we'd wait maybe a week, load the bed of the pickup with No. 2 washtubs and 20-foot "minnow" seines and head to the flooded river.
We'd wade the shallows where the swelled Trinity had inundated acres of grasses and shrubs, make drags with the seine and reap a red, tail-snapping harvest of crawfish. We easily filled three or four of the 15-gallon galvanized tubs with huge "swamp reds."
The crawfish were there because shallow, flooded terrestrial vegetation - the kind of habitat created by spring floods - kicks crawfish reproduction and growth into high gear. The crawfish population booms as the crustaceans take advantage of access to abundant cover and forage found in the flooded areas.
The flooded shallows also drew another aquatic creature that depended on these seasonal floods for its continued existence. We'd encounter them now and again on our crawfish sorties, often hearing them before we saw them.
Alligator gar - big ones, 5-footers and longer - would come out of the river and gather in the grassy, weedy shallows. Sometimes there would be dozens of them, jammed almost side to side in water a foot or two deep, their olive-color armored backs out of the water and that wide, spotted tail waving like a flag.
These collections of big gar would, on some cue known only to them, begin a frantic writhing and twisting, some fish slithering over the backs of others while others bumped and slammed nearby fish. Water flew and splashed, and the whole affair made a considerable racket.
The fish were spawning.
Flooding is critical
Alligator gar, by far the largest freshwater fish in Texas, require spring or early-summer floods to successfully reproduce.
It takes more than a decade for a female alligator gar to reach sexual maturity, and about half that for males. When water temperature climbs into the 60s, these adult fish develop eggs and milt in anticipation of spawning. But it takes a flood to trigger that effort.
Alligator gar spawn in 68-to-82-degree water covering flooded terrestrial vegetation. They wait in rivers and streams and bayous for rivers to rise and spread over the floodplain, then move into the shallows where collections of male fish gather around gravid females and, in the flurry described above, the female releases eggs that the males fertilize.
The resulting fertilized eggs are sticky and attach to the flooded terrestrial plants. The eggs hatch in two or three days, and the larvae, which have a sucker-like appendage, remain attached to the vegetation for 10 days or so until they are large enough to swim away.
If the river doesn't flood sometime between, roughly, March and early June, alligator gar won't even attempt to spawn. And if water level falls and exposes the eggs or the larval gar, the spawning effort fails.
Because alligator gar are such long-lived creatures - they can easily live 50 years or so, and fish more than 90 years old have been documented - they don't have to successfully spawn every year to maintain their population. But they do have to be somewhat successful every couple of years.
And on the Trinity and other Texas rivers that represent some of the final strongholds of what has been a shrinking national population of alligator gar, successful spawns, like spring floods, haven't exactly been regular occurrences.
On the lower Trinity, the fairly-regular crawfish "runs" ended not long after Lake Livingston was constructed. The Livingston Dam helped manage flooding downstream, blunting duration and extent. This was good for people living in flood-prone areas along the river. It was not so good for crawfish or alligator gar.
And maintaining healthy alligator gar populations has become a concern in Texas.
Over the past couple of decades, opinions and attitudes toward alligator gar have shifted. Once almost universally loathed as destructive predators that damaged populations of "good" fish such as largemouth bass and crappie and mercilessly persecuted and killed at any opportunity, alligator gar now are seen by many as a crucial part of freshwater ecosystems and a valuable recreational resource.
Research has consistently disproved the long-held belief that alligator gar prey heavily on game fish. Studies on several Texas lakes, including Sam Rayburn, Choke Canyon and Falcon, indicate largemouth bass and other "sport fish" make up, at most, 20 percent of gar diets and 10 percent or less in most waters. The gar feed on the most abundant and easily caught species - shad, buffalo, carp, mullet.
Considerable fervent and vocal anti-gar sentiment remains, especially on lakes where bass fisheries are struggling and among those who believe fewer gar mean more "good" fish. But, increasingly, anglers and bowfishers see Texas' alligator gar as something to be managed and maintained.
Once found in 14 states, alligator gar have been either wiped out or seen their numbers reduced to remnants in 11 of those states. Only Texas, Louisiana and southern Mississippi have appreciable naturally self-sustaining populations. And Texas has the most truly large gar; the world-record rod-and-reel caught gar, a 279-pounder, is a Texas fish. The Trinity River is considered the top "trophy" gar fishery in the world, drawing anglers from across the globe.
Efforts to protect Texas gar from over-exploitation began only recently. In 2009, the Texas Parks and Wildlife Commission adopted the first limit of any sort for alligator gar, imposing a one-fish-per-day bag limit. That rule has proved unpopular in some quarters. But it has, according to the best information Texas Parks and Wildlife Department has gathered, kept harvest of alligator gar low enough to prevent a decline in the population.
But concerns about the vulnerability of alligator gar during their irregular spawns has the agency considering a new regulation. At urging of the Texas Parks and Wildlife Commission, TPWD has proposed a rule that would allow the agency's executive director to temporarily prohibit taking or attempting to take alligator gar in an area where conditions - water levels, water temperature and other factors - are conducive to gar spawning. The closure could last no more than 30 days.
Insights into just how infrequently alligator gar have successful spawns played a large role in the push to allow the temporary closures. TPWD research of the alligator gar population in the middle section of the Trinity River indicated that in 21 years of the 30-year period, 1980-2010, reproductive success was nonexistent or very small. Only five years saw strong reproduction, the most recent coming in 2007.
Vote coming this week
Alligator gar are particularly vulnerable to harvest, especially by bowfishers, during these infrequent spawns. The fish, often in large groups, are crowded together in shallow water, making easy targets.
Drought and man-caused changes in hydrology have resulted in fewer successful gar spawns in recent years. Having the ability to temporarily protect those fish during the rare instances when they have near-perfect spawning conditions is seen as a way to help ensure Texas' populations of these important fish remain healthy.
The Texas Parks and Wildlife Commission will vote on the proposal this coming week at a public meeting in Austin.
Public comment on the proposal has been overwhelmingly in opposition to the rule, TPWD staff said this week.
What Texas' alligator gar really need are a few good, wet springs when the rivers swell and flood bottomland for a couple of weeks or more allowing these iconic creatures to get about the business of making young gar. Too bad someone can't pass a regulation that makes it rain and lets rivers and the creatures in them follow their natural rhythms.