By Louie Stout

Young bass stocked into Koontz Lake seem to be surviving pretty well, but the future of the fishery continues to be impacted by lack of habitat.

The Indiana DNR was there last spring surveying the success of stockings that occurred in 2019 (20,000 2-4 inchers) and 2020 (11,000).

Koontz has had a history of producing big, older bass, but the DNR is concerned that spawning successes have diminished well below the state average.

It’s not normal practice for the state to stock bass in a natural lake, but Koontz was in need of something given the low success of natural reproduction.

“We were seeing hardly any fish surviving from natural spawns and that’s due to poor habitat within the lake,” said District Fisheries Biologist Tom Bacula. “We’ve shocked some nice fish but not the numbers, so we had some bass fingerlings available and decided to see if we could give the lake a boost.”

Bacula said last spring’s survey showed quite a few 2- and 3-year old fish but very few younger fish. They didn’t see many of the quality bass, with the largest captured being 17 inches.

“We were encouraged by the number of 10- to 14-inch fish we saw in our survey,” he added. “We’re hoping those fish will produce successful spawns in the coming years.”

Part of the setback in bass populations occurred in 2012 when the lake had a major infestation of milfoil. The entire lake was chemically treated prior to a major drought that summer.

“Had we known we the drought was coming, we wouldn’t have allowed it,” said Bacula. “However, we didn’t get the rain to mix the chemical and it wound up killing other plants as well. We’re seeing some plant recovery, but we also are getting more algae and not enough plants.”

The lake lacks cover. Bass spawn on the flats, but the fry has no place to hide and gets gobbled up by predators or starves to death.

“In addition, the lake has a shad population (that competes with young bass for zooplankton food) and a fair number of carp that uproot the plants,” Bacula explained.

The Koontz Lake Conservancy District recently contracted a company to install aeration systems throughout the lake. The company claims the aeration will move the water and break down the nutrients.

Bacula says the DNR has not seen such a plan in Indiana but it will monitor the success of the system and continue to evaluate the fish population.