MARY LOUISE KELLY, HOST:
State and federal officials flipped the switch on a $7 million underwater boombox today at a dam in Kentucky. The bioacoustic fish fence is just the latest effort to try to halt the invasive Asian carp. From member station WPLN, Jason Moon Wilkins reports.
JASON MOON WILKINS, BYLINE: Barkley Dam in rural western Kentucky is considered a pinch point for controlling the spread of Asian carp, and with lots of dead fish floating around, it's also kind of a pinch your nose point.
UNIDENTIFIED PERSON #1: Smells great, don't it? Yeah.
UNIDENTIFIED PERSON #1: Carp are already jumping. It will not be a good day to see them jump.
WILKINS: Oh, yeah. Look at that. Wow.
Looking down, you can see a few fish popping out of the calm, flat lake, but a split second later...
(SOUNDBITE OF WATER SPLASHING)
WILKINS: That's hundreds and hundreds of carp flying into the air like a big, boiling pot around a small electrofishing boat. It's one of the methods used to contain an invasive species brought to the U.S. decades ago to help clean fish ponds and sewage systems. Since then, they've dealt millions in damage to economies and ecosystems. For Southern states, the most concerning of the four Asian carp species is silverhead, the leaping kind famous in viral videos for smacking boaters in the face.
(SOUNDBITE OF YOUTUBE VIDEO)
UNIDENTIFIED PERSON #2: (Laughter).
UNIDENTIFIED PERSON #3: We got two, and yes, they hurt.
WILKINS: They don't like loud noises, and British engineer David Lambert is using that against them by blasting carp with a...
DAVID LAMBERT: A bubble curtain - simple as that.
WILKINS: A bubble curtain doesn't sound intimidating, but each tiny bubble contains noises up to 160 decibels, like the inside of a jet engine but tuned especially for carp. A U.S. fish biologist calls it a disco barrier because it also uses lights shooting through the bubbles to scare away fish. Now, Lambert wouldn't describe the sound it makes.
LAMBERT: Well, that's the proprietary nature of it, so I'm not going to actually imitate it now.
ANDREW REEVES: It's terrifying.
WILKINS: That's journalist Andrew Reeves, who wrote a book on Asian carp. Officials in Canada played him the noise they're using, which he describes as...
REEVES: An outboard motor that is constantly being revved again and again and again.
WILKINS: This system has worked well in other settings, but this will be the biggest field test ever deployed for carp. Reeves says experts are excited, but they've redefined success.
REEVES: They really don't talk much about eradication simply because they know that at this stage in the game, it's impossible. Asian carp will be a presence in American waterways forever.
WILKINS: If the disco barrier works in Kentucky, officials plan to ask for more funding for other areas as early as next year.
For NPR News, I'm Jason Moon Wilkins. Transcript provided by NPR, Copyright NPR.