John R. Koelmel’s surprise departure as First Niagara’s president and chief executive officer is only the latest in an ever-growing list of prominent departures across Buffalo Niagara’s business, politics, sports and entertainment scenes.

Here are some other high-profile or longtime leaders who have vacated their posts:

• Reggie Witherspoon was fired March 15 after a 14-year tenure as head basketball coach at the University at Buffalo.

• Ryan Fitzpatrick, the Buffalo Bills’ starting quarterback, was released by the team on March 12.

• David F. Smith, chief executive officer of Amherst-based National Fuel Gas Co. since 2008, moved to the company’s executive chairman of the board earlier this month. Ronald J. Tanski, a 34-year veteran with the company, to the role of National Fuel’s CEO.

• Lindy Ruff was fired as coach of the Buffalo Sabres on Feb. 20 after 15 seasons behind the bench. Ruff was replaced by interim head coach Ron Rolston.

• Stanford Lipsey, the 32-year veteran publisher of The Buffalo News, stepped down Jan. 1 to become publisher emeritus. Lipsey was succeeded as publisher by News President Warren T. Colville. Lipsey’s departure came only months after Margaret M. Sullivan left her position as editor of The News and became public editor at the New York Times. She has been succeeded by Michael K. Connelly.

• Louis Grachos, the 10-year director of Albright-Knox Art Gallery, left his post at the start of this year for a job in Austin, Texas. Grachos was replaced by Janne Gallen-Kallela-Sirén, director of the Helsinki Art Museum in Finland.

• Chan Gailey was fired Dec. 31, 2012, as the head coach of the Buffalo Bills after three seasons. Gailey was replaced by Doug Marrone, who was the head football coach at Syracuse University.

• Leonard R. Lenihan, who led the Erie County Democratic Party for a decade before stepping down last year, was succeeded by 34-year-old Jeremy J. Zellner .

• The Rev. Edward U. Kmiec, bishop of the Buffalo Catholic Diocese, was officially succeeded Aug. 10, 2012, with the installation of Bishop Richard J. Malone.