Mohegan — Mitchell Etess, the gaming executive whose name and affable manner have long been synonymous with Mohegan Sun, announced Thursday that he will begin transitioning toward retirement.

Etess, president and chief executive officer of the Mohegan Tribal Gaming Authority, revealed during a conference call with financial analysts that the authority will name a new president who will eventually succeed him as CEO. During an indefinite transition period, Etess will continue to serve as CEO.

“The transition will last as long as is appropriate,” Etess said, adding that he will remain beyond the end of his current contract, which expires June 30, 2015.

“This is entirely my idea,” Etess, 56, said in an interview.

The surprise announcement comes in the middle of the Mohegan authority’s efforts to expand, efforts that have encountered setbacks in recent months. In September, the authority failed to win the Greater Boston casino license for a project it proposed in Revere, Mass., losing out to Wynn Resorts’ plan for nearby Everett. Days ago, Pennsylvania gaming regulators, in awarding a Philadelphia casino license, rejected a project in which the Mohegan authority was a partner.

The authority remains in the running for a casino license in New York state and is involved in other projects as well.

Etess joined Mohegan Sun nearly 19 years ago as senior vice president of marketing. He became president and CEO of Mohegan Sun casino in 2004, and added the responsibilities of president and CEO of the authority, which operates Mohegan Sun and Mohegan Sun at Pocono Downs in Wilkes-Barre, Pa., in 2006. He relinquished the Mohegan Sun casino titles in 2011.

“It’s not that I’m tired — though the last six years or so have been more debilitating than the prior 13,” Etess said of his decision to transition toward retirement. “You get to a point where you begin thinking about what’s right for you and your family.”

Etess, who lives in Lyme with his wife, Karen, said she “has sacrificed an awful lot over the years. We’re looking forward to spending more time together.”

Beyond that, and playing more golf, he said he has no specific plans for what he will do when he steps down.

He said that in the months ahead, he would like to focus on the authority’s venture in New York’s Catskills region if the authority wins one of several casino licenses expected to be awarded by New York gaming regulators. The proposed Mohegan Sun at the Concord would be built at the former site of a resort hotel that once competed with Grossinger’s, the resort Etess’ family operated during the Catskills’ heyday as a vacation destination.

“I’m fortunate in that I’ll be able to see things along for a while. I’ll be able to see the future of the organization,” he said.

Mohegan tribal Chairman Kevin Brown called Etess’ announcement “a bittersweet moment.”

“He’s been at this for two decades and he’s given it everything he’s had,” Brown said. “I can’t tell you how fortunate I was when I was coming on board (in 2013) to have someone like Mitchell at the helm. He has great energy and great vision. … We’ve grown a lot of tribal members into management positions at the casino and much of that is due to Mitchell’s leadership.”

The authority expects to have the new president in place by April 1.

“We have some internal candidates but to make sure we capture the entire realm of possibilities, we will look externally as well,” Brown said.

b.hallenbeck@theday.com

Twitter: @bjhallenbeck