Geese glide across the water like a scene from a post card. People take out their cameras and smartphones, children feed them hunks of bread.

Below the water’s surface though, it’s a literal shit show. Each Canada goose generates about 1.5 lbs, or more than half a kilogram, of droppings per day.

“Take a pound of butter. Take two of them. Then cut them up into little pieces. Then take it and throw it all over a piece of grass,” said Steve Wambolt, the creator of the Goosebuster drone. “And then do that times 1,000.”

At Petrie Island’s beaches, favourite spots for geese, people can step around the feces on land. But when a flock floats in the water nearby, the poop dissolves and creates a dirty, messy soup just offshore.

In response, the City of Ottawa put Wambolt on the payroll. Since 2013, he’s flown noisy drones with flashing lights to scare geese away from the island’s two beaches.

“I go down there at two o’clock in the morning and fly my drone around this pitch black island,” he said. “You see this cool thing buzzing around—no one has a clue what I’m doing—it’s chirping and making sounds.” He does this for about half an hour. The geese coming up the Ottawa River hear the sound of the drone and see the flashing lights. Then they pass Petrie Island by and head further upstream.

Since he started flying his drones there, there have been fewer high-level E. coli days during the summer.

No one wants to swim in nature’s toilet. People can get sick from bacteria in goose droppings, because where there’s poop, there’s E. coli. Measuring it is a good way to know if other dangerous bacteria, like salmonella, are in the water, because they tend to live under similar conditions.

The city measures bacteria levels at beaches every day in the summer. Health Canada recommends closing a beach when the levels get to 200 E. coli colonies in 100 ml of water. Ontario is stricter, so Ottawa closes beaches at a level of 100.

Rainy days tend to stir things up, but goose turds are one of biggest reasons for increased bacteria at public beaches, according to Allan Crowe, a scientist formerly with Environment Canada.

In 2012, Petrie Island Bay beach had 18 days of levels more than 100 and Petrie Island River beach had 10.

In 2013, after Wambolt started operating the drones, the Bay beach had four days of levels more than 100, while the River beach had nine.

Wambolt said the beach staff who clean up the poop on land reported less droppings since he’s been flying his drones. Beachgoers also said they noticed less poop.

Geese at beaches is a widespread problem. In the early 20th century, conservationists were afraid Canada geese were doing to die out. The government protected them. By the end of the century, their population boomed. But so did E. Coli levels at beaches.

There are guides to getting rid of geese on government websites, like Environment and Climate Change Canada. There are also organizations like Geese Peace that specialize in conflict management between geese and people.

Cities and businesses across North America have tried to get rid of geese by poisoning their eggs, installing strobe lights and noisemakers or spraying the ground with scents geese aren’t supposed to like. These methods either don’t work or only for a short time.

Wambolt’s Goosebuster drones are effective and they’re beginning to be in demand across the continent. For example, he’s set up chicken and shrimp farmers with drones to keep geese and other birds from contaminating the farms with their droppings.

“There are millions of birds in the world—they’re going to poop. We can’t control that. What we can control is where they poop.”