The Wampanoag Tribe of Gay Head (Aquinnah), the first federally recognized American Indian tribe in the commonwealth, is going through a period of significant change as it pursues plans to build a casino in an uncertain economic and regulatory climate.

The hope of building a casino in southeastern Massachusetts has been thwarted by state officials, and a previously announced plan to convert the tribal community center to a bingo hall appears to be stalled.

No application has been filed with the town and the still-unfinished building has no certificate of occupancy permit.

Meanwhile, there are signs of internal change. Tribal administrator Tobias Vanderhoop has resigned his post, the chairman of the tribe confirmed last week.

Chairman Cheryl Andrews-Maltais said Mr. Vanderhoop resigned last month.

“While it’s always sad to see someone you really like leave a position to move on, it was not only expected, it was inevitable,” she told the Gazette in an email. “The position is a really big job and consumes so much of your personal life as well as your professional career.”

An Islander who received a master’s degree in public administration from Harvard University’s Kennedy School of Government, the first tribal member to do so since 1665, Mr. Vanderhoop took over as tribal administrator in 2008.

In her email Mrs. Andrews-Maltais said the tribe is proud of Mr. Vanderhoop’s accomplishments and “grateful for the time and commitment he gave us.”

“We also understand that he has a lot more to do and contribute outside the tribe as well,” she wrote. “We will be following his career with eagerness and pride because I believe he has an even brighter future yet to come. His success is a success for all of us.

“Our loss is someone else’s gain.”

She said the tribe would advertise for the position.

Reached by telephone yesterday, Mr. Vanderhoop had no comment.

The annual tribal council elections were held last weekend. Mrs. Andrews-Maltais said Jonathan Perry, Leigh Moreis and Beverly Wright were reelected to the council along with newcomer Steven Craddock.

It is understood that the council is considering adopting a rule that would bar a tribal council member from also serving as a selectman. The rule has not been voted on yet, sources said, but may be considered before the end of the year.

Council member Beverly Wright is also an Aquinnah selectman.

At the time of her candidacy for selectman in 2011, the state ethics commission cleared her to serve on both boards.

The decision was based in part on a 1992 legal opinion, which found that the tribe is not a business, and tribal members who are also elected town officials can, with public disclosure, vote on matters that have a financial impact on the tribe.

But the opinion also states that if the tribe were to establish a “corporate entity for the purpose of developing real estate,” a town official who is a member of the tribe would be required to abstain from decisions “if the corporation sought a permit from his municipal board.”

The tribe does have a corporate entity, the Aquinnah Gaming Corporation, an affiliate that was formed 15 years ago for the purpose of developing a casino. Mrs. Andrews-Maltais heads the corporation, and Ms. Wright is not a member.

She declined to comment this week about her dual role as a selectman and member of the tribal council.

Aquinnah selectman and board chairman Spencer Booker is also a member of the tribe, although he is not a member of the tribal council.

But with two of the three selectmen being members of the tribe and questions mounting over the tribe’s casino plans, Mr. Booker admitted that the potential for conflict is real.

“It’s elephant in the room as of late,” he said of the casino issue. “Would I have to say I’m conflicted about it? Yes, but at the same time I understand as a selectman I am at the will of the people. I represent a constituency of people, no matter what their nationality or ethnic background may be. That’s where my allegiance falls currently, as a selectman and not necessarily the view of one particular ethnic group . . . my ethnic background has to be put to the side as I make decisions that are best for the town.”

Camille Rose, a former Aquinnah selectman, said competing interests between the town and the tribe have long been an issue.

“The most dramatic conflicts were where we did not have a common goal,” she said. “It’s very difficult politically, there are no rules to follow.”

She also said the tribal demographic is changing, with many members now living off-Island. “They wouldn’t necessarily have the understanding of the goals or the problems that we have,” she said. “I think when the tribe first got [federal] recognition there was really no perception of a difference between the town and the tribe, because most of the tribe lived here in town. We had common goals but they’ve diverged . . . there’s less of a sense of belonging than there was before.”

But selectman Jim Newman downplayed the conflicts.

“There so few issues that have come up,” he said. “The tribe is always very quick to help in any emergency. The tribe does a great deal for the town in terms of helping the town in times of need, and that’s big. People don’t get that.”

As for the casino issue, he said outside of the selectmen’s discussions in executive session with their town counsel about potential legal matters, “we have not discussed it with the town because nothing has been done officially to notify us. It’s not like it’s not there — it’s there and we’re prepared for it.” And he had warm words of praise for his two colleagues on the board. “There’s more imagined discord than there really is,” Mr. Newman said. “We’re really lucky to have Spencer and Beverly, who are fair and wise.”