The peak population of the offbeat art and music festival was 52,385 on Friday, down 1.7 percent from 53,735 a year ago, said Gene Seidlitz, manager of the Bureau of Land Management's Winnemucca Field Office.
The agency established a daily attendance cap of 60,900 for this year's gathering.
The annual celebration of radical self-expression is held over the week leading up to Labor Day on the Black Rock Desert, 110 miles north of Reno.
Last year, BLM officials placed organizers on probation and threatened to pull their license after finding them in non-compliance for exceeding the attendance cap at the 2011 festival.
That gathering drew daily crowds of more than 53,000 on two different days. A daily cap of 50,000 was allowed at the time under terms of Black Rock City LLC's special recreation permit with the BLM.
It was the first time Burning Man had been placed on probation since moving from San Francisco to Nevada in 1990. The gathering is overseen by the BLM because it's staged on public land.
Seidlitz had warned that if BRC was placed on probation two straight years, his agency may suspend or cancel Burning Man's permit and/or deny future permit applications.
"I think we got their attention with the non-compliance, and they made a better attempt to adhere to the limit this year," Seidlitz told The Associated Press. "I think they came up with a better plan for a buffer so they didn't risk another possible non-compliance."
Burning Man spokeswoman Marian Goodell said organizers manage ticket numbers in an effort to manage the festival's population.
"We always work to manage our population numbers," she said Sunday. "For us, the cap is the top level that we would be functioning well. We need to manage ourselves in that area and that's what we did."
BRC maintains it didn't exceed the attendance cap last year, and is appealing the BLM's finding of non-compliance to the Interior Board of Land Appeals.
Seidlitz said this year's festival went smoothly and no major problems were reported.
As of Saturday, BLM spokesman Christopher Rose said, 22 participants had been arrested and 230 others had been cited for drug and other violations. Another 441 verbal warnings were issued to revelers for everything from speeding to washing their hands and dishes on the playa.
Thousands of participants left the gathering well before its traditional climax Saturday night with the torching of its 40-foot signature effigy. The event officially ends Monday.
"Tons and tons of people decided not to stay through Friday and Saturday," Goodell said. "I think the reason is we have an eight-day event and some people come early and think four days is enough."
Other "Burners" leave early to avoid the mass exodus usually seen over the holiday weekend, she added.