By DAVID RAINER Alabama Department of Conservation and Natural Resources
At the recent Alabama Conservation Advisory Board meeting in Eufaula, local bait and tackle shop owner Joe Young expressed his concerns about Lake Eufaula’s bass population. Wildlife and Freshwater Fisheries’ District IV Fisheries Supervisor Ken Weathers was already aware of the downturn in the health of the bass in the lake, known nationwide for its bass fishing.
Alabama and Georgia biologists plan to meet soon to compare sampling data and discuss possible management options to improve the largemouth bass population in Lake Eufaula, an impoundment on the Chattahoochee River.
In this instance, the bass anglers’ mantra of “catch and release” may be detrimental to the current Eufaula bass population. Weathers attributes the current poor bass condition at Eufaula to three factors. The first is that anglers are throwing too many bass back, which leads to overcrowding. Second is the decline in the amount of aquatic vegetation in the lake. Finally, that decline in vegetation has caused a shift of forage species from sunfish to shad. Sunfish provide a more stable forage base than shad.
Bass samplings conducted in March easily revealed that they were not in good shape. Larger bass had condition factors in the low 80s, while the smaller bass averaged from high 80s to low 90s. These condition values are characteristic of too many fish for the available forage.
“Anglers just aren’t taking enough fish out of the lake,” Weathers said. “A pond or lake owner knows that they need to control their population of bass. This also applies to a reservoir like Eufaula. This trend has been going on for several years.”
During a 10-week creel survey this year from late February through early May at eight different Eufaula boat ramps, there were 230 interviews of 437 anglers with 835 bass reported as caught. Only 18 bass were kept, a mere 2 percent of the total catch. Even with the 14-inch minimum length limit at Eufaula, over half of the bass caught were legal but not harvested.
“It is important for anglers to understand the role of harvest in managing a fish population,” said Stan Cook, Fisheries Section Chief. “Bass creel and length limit restrictions are designed to improve the health of bass by directing angler behavior to produce a desired outcome. Sometimes ‘catch and release’ is not in the best interest of improving a bass population. We need anglers to practice a selective harvest in order to set a state of balance between bass and available forage. When this occurs, growth, condition and yield of larger fish improve.”
Coincidentally, an FLW bass tournament happened to be going on at the same time of the advisory board meeting. Weathers went to the tournament weigh-in and confirmed what he and Young had suspected – indeed the bass were not in the best of health for a variety of reasons. It took only 13 pounds, 14 ounces (five fish) to win the tournament.
“They were still catching decent fish in early February, but this spring the weights have been down significantly,” Weathers said. “It’s taking anywhere from 13 to 15 pounds to win, where you had to be in the 20s just to be in the money last year.
“It is very typical of a bass fishery that has too many fish for the available forage to produce bass that are skinny and in poor condition. Their overall health is not good. Usually biologists and anglers will easily see more fish with diseases and sores.”
Weathers said the maladies that affect fish, such as Columnaris (a bacterial infection) and Epistylis (a protozoan infection) are always present in the environment. Stressed fish are more susceptible to the infections. Weathers said the vast majority of the fish recover from the infections, and that affected fish that are caught are suitable for human consumption. Weathers said only in extreme outbreaks can these infections result in fish mortality.
“Spawning is a real stressful time, especially the bigger fish. If they are in poor condition anyway, you’re going to see lesions, sores, tail rot and abrasions. We see sores and lesions every year. That’s not uncommon at all. It is uncommon for this many to have those lesions. Of the fish I looked at from the tournament, 21 percent of them had lesions. That’s high. Usually it’s less than 10 percent. ”
The large reduction of aquatic vegetation has impacted the fishery. When there is abundant aquatic vegetation bass will have plenty of places to ambush sunfish like bluegills and shellcrackers in relatively shallow water. In 2007, the U.S. Army Corps of Engineers released 13,440 grass carp in the lake, followed by 5,200 more in 2009. The Corps also sprayed herbicide on several hundred more acres of vegetation, which limited the vegetation to the northern section of the lake.
“When you’ve got a lot of weeds in a lake, bass primarily feed on sunfish,” he said. “With sunfish as the primary forage, you’re going to have a lot more stable bass population. But it’s changed now.”
When the bass transition from shallow grass to deeper river and creek ledges, the forage base changes to shad, which tends to be available in boom and bust cycles. Weathers said the current shad population offers very little forage for the larger bass because of several years of below average shad spawns. However, numerous threadfin shad were observed in coves spawning this spring.
“Most of the shad observed during spring sampling were 3- to 4-inch threadfin shad,” he said. “This would explain why bass up to 16 inches are in fairly good condition, but larger bass are in poor condition. The size of forage needed for these bigger fish is really low right now. A big bass will get skinny fast chasing tidbits around on deep points and channel ledges.”
Weathers, however, said this situation is not new to Eufaula, which had similar conditions before the aquatic vegetation began to spread in the early 2000s.
“Eufaula used to be primarily a shad-driven lake,” he said. “Shad are notorious for cycling. So back in the 80s and 90s, when there were plenty of small shad, the little bass would be growing good. When there were big shad, the bigger bass would be in good shape, but there wouldn’t be many bass because you don’t get good recruitment when you have big shad.”
Weathers is concerned that the condition of the bass population may not have bottomed out just yet.
“I think it’s going to get a little worse before it gets better,” he said. “The threadfin shad were really spawning heavily in the backs of the coves this spring, but you’ve got to give them time to grow to feed these bigger bass.”
“From talking to anglers, you can catch a lot of bass right now, but they’re going to be below 15 inches,” he said. “As far as abundance, that’s good. But the condition of the fish is poor. The disconcerting thing was how fast it went down on the bigger fish. It went from one year when it took 22 to 25 pounds to win with a five-fish stringer to 13 to 15 pounds. That’s pretty quick.
“But the lake can bounce back. As far as the abundance of the bass population, it’s there. If we can thin down the smaller fish and people continue to catch and release the bigger fish, I think within two years it will be back to a good fishery. But if the Corps continues its policy of managing for very little aquatic vegetation, we’ll likely go back to a cyclic pattern like the 80s and 90s. We had some great years in the 80s and 90s, but we had some stinking years, too.”
PHOTOS: Long-time Eufaula fishing guide Jackie Thompson (photo by David Rainer) unhooks a fat, healthy largemouth bass that was caught in Lake Eufaula several years ago, when aquatic vegetation was plentiful. A combination of factors has caused a decline in the health of the Eufaula bass population, as indicated by the condition of some of the fish weighed in recently at an FLW tournament (photo by Ken Weathers).