TPWD studies impact of alligator gar on bass

Published on Saturday, 28 June 2014 21:25 - Written by Steve Knight outdoor@tylerpaper.com

The only thing that has dropped more than the water level at Falcon Reservoir in South Texas has been the quality of bass fishing.

This is nothing new. As the region dries up the lake level falls 20, 30 or more feet at least once, maybe twice every decade, and with it goes one of the state’s best big bass fisheries. With ongoing drought conditions the lake is currently down about 30 feet, leaving the 83,600-acre reservoir only about 30 percent of its normal size.

Not long ago Falcon was producing 100-pound bass stringers and was arguably the best tournament bass lake in the state. Forty-pound-plus one day stringers were benchmarks, but with the low water level the bottom has fallen out.

And the blame game has begun. That isn’t new either, but after casting doubt on just about everything else over the last three decades locals this time around are blaming alligator gar.

The fishermen are saying the gar are eating the largemouth bass and not only want the one-fish daily gar limit changed, they want it eliminated. The fishermen are complaining to everyone that will listen, causing Texas Parks and Wildlife Department to take action and do another alligator gar research project this summer.

“What they are saying about gar impacting bass, it has never been shown to happen before, but no one has looked at it thoroughly. There was a study on (Sam) Rayburn in the 1980, and yes they had some bass in them,” said Randy Myers, TPWD Fisheries district biologist from San Antonio.

Myers said there is concern about the future of alligator gar as their numbers dwindle across much of the country. Texas got onboard with conserving the fish in 2009 when it adopted a one-fish daily bag limit. Restrictions were tightened even more this summer with the agency’s Executive Director given authority to temporarily close gar fishing on portions of rivers when water levels were prime for spawning activity in the spring.

However, Myers said much of the data being used came from Coastal Louisiana, and as it turns out there is not much comparison to South Texas.

“Things can be different and are different here,” Myers said of Falcon and other lakes in South Texas.

For example, while alligator gar numbers dip in other portions of the state, scientific studies and incidental information show they are up in lakes like Choke Canyon and Falcon.

Myers said during a trip last October to determine how researchers would collect the fish they brought 28 fish to shore. With just that small sample he said biologists learned the fish grow faster and sexually mature than what had been found during studies in Louisiana.

He added that along with stomach analysis this study is also attempting to answer other questions about alligator gar that aren’t clear. Some of the early results have been surprising.

“The gar here reached 100 pounds in five years, and we found females with eggs in them that were 3 to 5 years old. A fish that grows to 80 or 100 pounds is eating a lot,” he said.

Based on stomach analysis of the alligator gar captured this summer for the research the fish are growing rapidly on a varied diet that includes bass, catfish, carp, freshwater drum and gizzard shad. With at least one more collection planned, Myers isn’t ready to say if the gar are eating enough bass to impact the Falcon fishery.

Instead he cited three things that could be having a negative impact, habitat because of water level, the effect of fishing by non-tournament and tournament anglers and predation by gar.

“At this point we are not able to separate them. The one thing we do not understand is the amount of gar in the lake,” Myers explained.

However, reports from April’s survey of 80 gar the researchers found just one bass. However, they also reported most of the other gar had empty stomachs.

That is in contrast with a previous study on nearby Lake Guerrero in Mexico that showed about half of the gar captured had bass in their stomachs.

Harvest of bass is still popular at Falcon. Even guides condone it. However, using a creel survey on the lake from January to June Myers estimated fishermen only take between 14,000 and 20,000 fish a year.

With its history of falling and rising water levels, Falcon’s bass fishery has always bounced back. That includes in 1995 when the lake was down more than 40 feet and 2003 when it dropped 53 feet.

“Bass peaked in 2009 to 2011. We had great water level events. In 2008 the lake went over full and in 2010 it went over full. Those water level events came after the spawn, but a lot of water still remained in there in 2009 and 2011. Under high water events that habitat is the best bass habitat you can have,” Myers said.

Based on angler catches, however, this time bass numbers have not responded. Myers noted that doesn’t mean there wasn’t the expected production, but the fish are not being caught by fishermen if it did. At the same time, he added, it does look like alligator gar numbers did increase.

Myers said he is going to wait until September to comment on the study findings. By then he said three-quarters of the data should be completed. At that time he said he expects to make a recommendation either to maintain the one-fish alligator gar limit or for change to his supervisors.