Thomas C. Short, president of the Intl. Alliance of Theatrical Stage Employees since 1994, has retired and been replaced by IATSE exec Matthew D. Loeb.

IATSE announced the moves — which have been rumored recently in Hollywood labor circles — on Thursday at the union’s general executive board meeting in San Diego. Business agents had been informing members in recent days of the developments (Daily Variety, July 30).

Loeb, who’s been an International VP since 2002, was elected unanimously. The below-the-line union credited Loeb with devising and implementing the organizing and bargaining strategies to expand IATSE’s jurisdiction and membership during Short’s presidency.

“I am not leaving for political reasons or for health reasons, but rather because I have learned that life is short and there is a great deal that I have yet to experience and enjoy,” Short said in a statement.

Short had a year to go on his four-year term as president. Loeb’s been division director of motion picture and television production for the past decade.

IATSE noted in the announcement that membership increased by more than 50% during Short’s tenure to cover more than 400 locals and more than 110,000 members in the U.S. and Canada.

During his tenure, Short was willing to criticize other Hollywood unions, including SAG and the WGA — particularly the latter due to long-running disputes in jurisdiction over animation writers and reality shows. He was especially upset with the WGA during its 100-day strike, taking issue with the WGA’s strategy of delaying contract talks and with the guild refusing to apologize for the strike’s economic impact.

IATSE also formed a strategic alliance a year ago with AFTRA, which has been in a bitter dispute with SAG on a variety of fronts.

Short has been a strong proponent of launching talks well in advance of contract expirations. That strategy is keyed to the notion that companies are more willing to agree to the most favorable terms in exchange for the guarantee of labor peace through an early deal.

In April, IATSE and the majors bargained for three days over the West Coast contract, which doesn’t expire until August 2009. Both sides reported progress but have not set a date to resume talks and probably won’t until the SAG contract stalemate is resolved.

Short’s been an IATSE member since 1968, when he was initiated into Stagehands Local 27 in Cleveland.

“I have put forth my energy and every effort to enrich this organization and enlisted the help of what I believe to be a phenomenal staff of intelligent, sophisticated and progressive individuals who have stood ready to work hard and assist in accomplishing the goals I believe we had to achieve in order to survive the many challenges facing this International,” he said in a statement Thursday.