Glacier National Park Conservancy’s president and chief executive officer has stepped down from his post, the fundraising organization has said.

Mark Preiss had served for nearly three years as the conservancy’s first and only chief officer since it formed from the merger of two smaller philanthropic organizations in 2013. He left recently for personal reasons and to spend more time with his family, according to Mo Stein, the chairman of the Conservancy’s board of directors.

“We respect him, we admire him and we wish all the best,” Stein said. “We admire his commitment to the community and to his family.”

Following a five-month search, the board selected Preiss to head the organization, which was formed after the merger of the Glacier National Park Fund and the Glacier Association.

The park fund had raised money from individuals and organizations to support projects focused on research, preservation, trails and education in Glacier — a mission similar to the new organization’s role as the park’s primary fundraising partner.

The Glacier Association had provided financial aid to the park and other federal sites through the proceeds of educational and interpretive materials at local bookstores.

“Mark was very helpful in the organization of the conservancy in those early days,” Stein noted. “We would say that tenure was successful; it set the foundation for the public-private partnership between Glacier, the National Park Service and the Conservancy that allows for the tools we need to achieve that margin of excellence. ... I think Mark was very effective in navigating that space.”

Before taking the job, Preiss worked as the manager of Ebey’s Landing National Historic Reserve in Washington. He also brought 25 years of experience working with nonprofit groups that collaborated with private and public organizations, including the National Park Service.

Since August 2013, Preiss oversaw a nearly 50 percent increase in the fledgling organization’s fundraising efforts and project funding, Stein said.

That effort required building strong relationship with donors and supporters beyond Glacier’s gateway communities.

“The Glacier family lives all over the world,” Stein said. “We’re reaching out to those 2.3 million people that visit the park, but we’re also reaching out to the millions of people that look at Glacier’s webcams, visit over time and recognize Glacier as one of the world’s most important classrooms.”

He said the organization has yet to determine its next steps in the wake of the departure of Preiss, calling those decisions “premature.”

While he declined to elaborate on the reasons for Preiss’ departure, Stein said Preiss left on good terms.

“It takes a village, it takes a really large village to do what we do,” he said. “We’re glad to have had Mark as a part of it.”