Although the official start of the Carnival season was still a couple of days away Sunday, a few people wandering the French Quarter sported the signature purple, green and gold of Mardi Gras. Col. Mike Edmonson stood out in his colors, too — the blue uniform of the Louisiana State Police.

Edmonson, the State Police superintendent, visited the Quarter on the last day of his troopers’ latest assignment in the city.

Nearly 40 troopers came to town to help the short-staffed New Orleans Police Department over a New Year’s holiday featuring a Sugar Bowl game that doubled as a semifinal for the college football championship.

Nearly 100 troopers helped patrol New Orleans over the summer after one person was killed and nine were injured in a Bourbon Street shooting in June.

A smaller contingent returned to help with Bayou Classic crowds the weekend after Thanksgiving.

About 150 State Police officers will be in town for Mardi Gras. But for the next few weeks, they’ll be gone, even though Mayor Mitch Landrieu has asked Gov. Bobby Jindal to let them stay, saying the troopers’ presence has made a big difference in the fight against crime.

Edmonson walked the streets of the French Quarter late Sunday afternoon, shaking hands with everyone he met. On St. Peter Street, he came across Nick Urso, a former Orleans Parish Civil Sheriff’s Office deputy, and his family, including a couple of young nephews.

Urso said that with the troopers in the Quarter, people “feel a lot safer” and are more willing to make their visit to the city’s oldest neighborhood a family outing. He said that when police officers aren’t around, “it’s like a free-for-all.”

At St. Peter and Royal streets, Edmonson ran into Ben Jaffe, whose family has operated Preservation Hall since the 1960s.

“Nothing really takes the place of having a visible police presence,” Jaffe said. “It makes a real noticeable, impactful difference.”

Jaffe said he would welcome “any kind of support from the state” to help out the city’s strained law enforcement system.

As Jaffe talked, vehicles started backing up on St. Peter Street because an ambulance responding to an emergency call a few blocks away had stalled traffic. Troopers stepped in and did something surprising: They opened up a portion of Royal Street, normally a pedestrian mall, to traffic to relieve some of the backup.

Edmonson’s tour of the Quarter was emblematic of the troopers’ approach to their job while they were in the city.

“I told my troopers, ‘Engage the public,’ ” Edmonson said. “If someone looks like they’re lost or someone looks like they’re scared or worried, walk up to them and ask if everything is OK.

“How do you find out what’s going on in a community, a neighborhood or a business area? You ask the people who are there every day.”

Edmonson said the mainly trouble-free Sugar Bowl weekend showed what additional law enforcement manpower can do for a city in need of more police officers.

Even hours before the troopers were to leave town, people were already feeling the loss.

As Edmonson did a television interview outside the temporary State Police office tucked away in a corner of the Cabildo, two men staggered along St. Peter Street in an apparent state of inebriation.

One of them spotted Edmonson’s uniform and yelled out, “I love the State Police. They’re good people. I miss you.”