Robots Setting Sights on Catfish-Eating Birds

It prowls the pond, on the hunt for pelicans and cormorants. When it’s close enough, splat!

It’s a solar-powered robot scarecrow that guards catfish and crawfish ponds with a water cannon.

The basic model has paddlewheels and pontoons; a student is building one to look like a big alligator.

There are still bugs to be worked out, but developers at Louisiana State University figure they may be able to talk to manufacturers about their project sometime next year.

“Some people have told us they tried alligator decoys,” said researcher Randy Price. “They said it worked really well for about a month, until the birds realized it was just a decoy.”

An 8-foot-long “robogator” might keep the birds fooled, he said.

“Catfish farmers are our biggest pressure right now. They’re losing a lot of fingerlings--baby catfish,” said fellow researcher Steve Hall. “That can cost them tens of thousands of dollars.”

Catfish farmers say they also spend thousands of dollars a year to scare the diving birds with sonic cannons or to kill them with poison or guns.

A University of Arkansas study at a state hatchery found that, even though cormorants showed up during only two of the study’s 15 months, they were by far the biggest predators. They ate more than a million catfish--fingerlings worth nearly $90,000, making up nearly half the fishery’s stock.

Hall, an aquaculture specialist, and Price, whose field is agricultural automation, figure their solar-powered invention might sell for $500 to $600.

“It sounds like it’d be real good for each individual pond. But no way you could afford it all around the whole farm, I would think,” said Rick Moyer, who has about 40 ponds at his aquaculture farm in Sunflower, Miss.

But Will Branton of Leland, Miss., said it would be worth at least a try on problem ponds. “We buy bird cannons. They cost $350, and they don’t work worth a darn,” he said.

He estimated that birds cost him $60,000 a year in losses, plus the time and equipment needed to scare them from his 42 ponds.

Moyer estimated that he spends thousands of dollars a year chasing birds by car, shouting and honking; shooting guns to harass them; and moving propane cannons from pond to pond.

The LSU researchers’ basic boat is a pair of pontoons supporting a solar panel “roof,” with a pair of paddlewheels.

Hall and Price were thinking about a radio-controlled “scarebot” when they got together last spring. Then they decided autonomy was the way to go. The less time a farmer had to spend tending the gizmo, the better.

One of their students is working on the gator. It has a moving mouth and tail; the big hang-up is finding waterproof paint that doesn’t eat away the foam silhouette, Price said.

There are two sorts of machinery to tell the boats where to go. One involves sensors that prompt it to back up and turn when it hits the shore; the other includes a camera and software to recognize color and motion. It’s quite good at finding a white shape (pelican) or black shape (cormorant) and moving toward it.

Recognizing motion is harder. “If you get a lot of wind, and as you get close to shore, it gets thrown off because it sees the shore moving relative to the boat,” Hall said.

The boat usually scares away the birds before it gets close enough to squirt them.

“We want to just haze them a little--chase them off the ponds and push them back into nature,” Price said. “We want to do that without hurting the birds.”