On a hot day at Dulles International Airport, a federal officer zeroed in on a tired woman, sniffing her suitcases and sitting down.

Hair-E, a honey-colored beagle, looked at his human handler, Don Polliard.

Do you have anything in that bag? Mr. Polliard asked the passenger a question.

She reluctantly said yes. The band was similar to Hair-E suspected. As Mr. Polliard instructed the traveler and her husband to take their many bags and go through a secondary round of inspections, Hair-E lurched towards a red plastic bag a carousel away.

Hair-E is one of 180 hounds deployed at airports, border crossings and postal depots across the country as part of the government's beagle brigade. They are wearing blue vests with government logos and are roaming airport corridors to detect and intercept banned foods and plants. With international travel returning to prepandemic levels, Hair-E and his colleagues are seizing an increasing number of banned goods.

Members of the brigade detect and intercept prohibited foods or plants that could carry diseases and wreak economic and ecological havoc on American agriculture. Credit...Shuran Huang for The New York Times

Young rescues that complete up to 13 weeks of training at a center in Atlanta learn to smell apples, oranges, mango, pork and beef. Their time in the field increases their olfactory capabilities. The majority of the dogs are placed at ports of entry after graduating from the program. When members of the brigade retire after a few years of service, they are usually adopted by their handler.

Smaller dogs like beagles are preferred to patrol baggage carousels while bigger dogs like labradors are preferred to sniff out docks and cargo facilities.

A regional agricultural canine adviser for Customs and Border Protection who worked as a handler for 15 years saideagles are not intimidating and people are usually happy to see them.

Don Polliard, an agriculture specialist for Customs and Border Protection, with Hair-E. Typical recruits for the brigade are young rescues that complete up to 13 weeks of training at a center in Atlanta.Credit...Shuran Huang for The New York Times

Even if the detection comes with a wagging tail, few travelers are overjoyed. The dogs and their handler aren't taking the food. beagles receive a treat, such as a pepperoni stick or tiny milk bone, when they discover something, while their handler is bound by the Agriculture Department's regulations.

Christopher Brewer, the Customs and Border Protection agriculture, said that they are not taking the ham to the back room because they are not their favorite person.

One of the layers of defense is the dog.

It could be a disaster.

Pork sausages and cured meats smuggled in from abroad are at risk of being transmitted through African swine fever, a disease that is not yet present in the United States.

Valerie Woo with her detector dog, Phillip. “Some of the passengers come from food-insecure countries or it’s their first international trip and they want to bring everything,” she said.Credit...Shuran Huang for The New York Times

The Medfly, a fruit fly that is considered one of the most dangerous pests in the world, is often found in fruit and vegetables in South Asia in May and June.

On a recent Friday, Hair-E and Phillip, two-year members of the brigade with golden eyes, patrol an arrivals bay bustling with European backpackers, retrieving canisters of holy water from the oversize baggage claim.

Every carousel crammed with luggage is preferred by the beagles.

Hair-E, the fastest and one of the most industrious dogs at Dulles International Airport, intercepts 12 to 18 prohibited items a day.Credit...Shuran Huang for The New York Times

Ms.Milbrandt said that they enjoy working. By watching them, you can see that.

In the first nine months of the current fiscal year, the beagle brigade has seized more than 96,000 items, which is on track to surpass the number of seizures in the previous two years.

Hair-E is the fastest dog at the airport, intercepting 12 to 18 prohibited items a day, including bush meat, fresh mangos and homemade goods.

During the height of the Pandemic, keeping the dogsmotivated was a challenge. Without a steady stream of suitcases, the five beagles stationed at Dulles were assigned to uncover food hidden in vehicles to keep their memories fresh.

The scent of certain things is more appealing than others. He looks at meat when he identifies it. Phillip likes the smell of fruit.

A recent jackpot for Phillip was a suitcase with 55 pounds of raw meat.Credit...Shuran Huang for The New York Times

The phantom smells of a sandwich or apple are caused by the dogs detecting residual odors from food that has been eaten.

Phillip's most recent win was a suitcase stuffed with 22 pounds of raw beef and 33 pounds of smoked goat meat. Even if it's her job to guard against it, she's sympathetic to the temptation.

She said that some of the passengers come from food-insecure countries and they want to bring everything. It's a piece of home for some.

There is a recent example of a large tin canister opened and resealed.

He said that they were certain that they had drugs. I turned out to be a homemade sausage. They were made by grandma.

He was asked to rank the canine officers he had worked with. He said they're all good dogs.

Certain scents are more enticing than others. Phillip loves the smell of bananas.Credit...Shuran Huang for The New York Times

Phillip rolled around on the floor, mugging for the camera, his colleagues and a reporter gathered around him, before coming to an abrupt alert.

He could smell something in the air.