Restoring West Boggs Lake: Plan to use chemical stirs controversy

Fishkills are done to manage fish population in a couple of circumstances: when invasive or non-native species have expanded into waters outside their native range, and when those species cause the decline of endangered or desired fish species through competition for food and predation.

In the case of West Boggs, the lake has been invaded by gizzard shad, which compete with bluegill and small bass for food.

In lakes with gizzard shad populations, bluegill growth is stunted and bass numbers eventually decline. 

Gizzard shad were introduced illegally to the lake in about 2000 or 2001.  

According to the DNR, bass will eat shad over bluegill, so the result is bluegill are able to reproduce unchecked. This results in more bluegill but, because of competition for food, bluegill growth is stunted. The bass population also slows because of increased food competition. Ultimately, the bass population can’t sustain itself. 

The drawdown currently taking place will lower the surface level of the lake. Once it reaches the desired level, DNR fisheries staff will begin removing as many bass and other sportfish as they can before the planned fishkill. Those fish will be moved to fisheries where they will spend the winter before being returned to West Boggs in the spring.  

Rotenone, a chemical that kills fish, will be used to eradicate the remaining fish. In addition to spraying the lake, 22 miles of creeks and streams will be treated. Concerns have been raised about rotenone’s links to Parkinson’s disease. 

Dave Kittaka, DNR fisheries biologist, said rotenone has been use by conservation departments since the 1930s, but is often used as “a last resort tool.” 

“When all other fish management practices have failed, if the conditions are right, a total fish renovation may be the answer,” Kittaka wrote in an email message. “There are many lakes in Indiana that have gizzard shad. Not all are bad, but when shad dominate the population and out-compete all species of fish for food and habitat, there is an unbalanced predator-prey relationship that often cannot be fixed with additional fish stockings.” 

Rotenone occurs naturally in several plant seeds and stems and is an EPA-regulated piscicide. Rotenone quickly detoxifies in the environment and has virtually no effect on mammals and birds. After the fish eradication, the lake will be allowed to refill. It will be stocked with hatchery-raised game fish and fish salvaged from the lake before the renovation. 

Kittaka said said all safety and application standards will be followed when applying rotenone. Rotenone is a restricted chemical because of its toxicity. 

Karmen Wagler of Loogootee is opposed to the spraying of rotenone. She, Pat Jones of Loogootee and others have attended public meetings on the project and scoured websites to get more information about rotenone. Wagler said the group is concerned about the health and environmental impact of the chemical and its link to Parkinson’s. Last week, they met with an attorney to consider their options in stopping or delaying the application of rotenone. 

“My concern is over data gaps in the safety information,” she said. “Over 700 gallons of broad spectrum pesticide will be dumped in public waters, but what can the average citizen do? … I can’t fathom this is going to happen just so we can get bigger bass.”

Wagler, who is a registered nurse, said she has also doubts about rotenone’s brief half life.

“I spoke with a mayor in California where it was used and it was still in the water six months later,” she said. “My question is, if they tell us we can come out next day, can I see the science behind it? No one can provide that to me.”

Wagler, who lives within walking distance of West Boggs Park, is also worried how the chemical could affect her son, who has autism.

“We do a lot at home to help his health. We eat organically and go above and beyond to keep him away from chemicals,” she said.

Wagler asserted she has no beef with the park itself.

“I love the park. It’s a great asset to the community,” she said. “My concern is this pesticide will wipe out the entire fish population.”

She also is worried what will happen if gizzard shad return to Boggs. Will another fishkill be needed down the road? 

“They did this in ‘94, and the shad came back,” she said. “Have we looked at all the other reasons we have this overabundance of shad? Before we poison an entire ecosystem, we should look at other factors.”

In 1994, the Division of Fish and Wildlife used rotenone to eradicate gizzard shad at West Boggs, and it has been used elsewhere in Indiana.

“The result was a highly productive game fish program,” said Kittaka. “Another successful program was created at Dogwood Lake at the Glendale Fish and Wildlife property. Dogwood Lake was renovated in 1976 ... and more recently in 2008 at Starve Hollow Lake in the Jackson-Washington State Forest. There is a long list of lakes that have been renovated in Indiana, beginning in the early days when it was the Indiana Department of Conservation.”  

The renovation project will begin once the lake is taken down to about 150 acres of water around the dam area. Kittaka explained the lake drain valve will be closed and the remaining water will be treated by boats with liquid rotenone. The remaining pools of water in the lake bottom will be treated by aerial application.

“In 1994, the lake was treated by a crop duster as well,” said Kittaka. “The aerial application will account for less than 10 percent of the total application of the lake. There are approximately 22.5 miles of seasonal flowing streams. These streams and ditches will be inspected by DFW staff. Any standing flowing water will be treated via backpack sprayer. As the lake drains, most of the streams will be dry, and we expect to only need to treat approximately two-thirds of the 22.5 miles.”

Mike Axsom, superintendent of Daviess-Martin Joint County Parks and Recreation, which manages West Boggs Park, said fishing at Boggs has declined as the shad have taken over.

“Fishing has been unproductive for a couple of years,” said Axsom. “There has been a shift in the type of visitation at the park. We have other opportunities that have picked up the difference.”

The lake renovation, although necessary for the lake’s future as a fishing destination, is not without its drawbacks.

“This is harmful to us in the short term, because fishing is not the only use of the lake,” he said. “We would normally have a lot of recreational boating here right now.” 

West Boggs Park brings in about $2 million in direct revenue a year. Visitors to Boggs frequent many area businesses outside the park. Axsom said the estimated total impact on the region from Boggs is $14 million. 

Axsom came to work at Boggs in 1994, making this lake renovation the second of his career. No one knows for sure how the shad got into the lake, but Axsom said it wasn’t by accident.

“After talking with the biologists over the years, we’re real certain they got in there with some human help,” he said. “Whether it was intentional to stock them in there or out of ignorance, but they were put there by somebody.”

The total cost of the renovation won’t be known until after the project is complete, said Kittaka, but he did say the cost will be “significant.” The lake should be at near normal levels by next April. 

For Axsom, he’s ready to see the lake restored. 

“We’re looking forward to having it fixed. I wish it had never got messed up to start with. It’s almost like going through surgery,” he said. “You don’t look forward to it, but you don’t have a choice.”