National Geographic Channel executive vice president of global content Steve Burns is leaving the network.
In a staff memo from Nat Geo president Steve Schiffman released Friday morning, Burns -- who has headed up Nat Geo's programming efforts since 2007 -- will leave "sometime in the next few weeks."
Nat Geo senior vice president of production Michael Cascio will serve as interim head of global programming "while the board actively looks for his successor," according to Schiffman.
Burns was responsible for bringing to the network such content as the Oscar-nominated film Restrepo, as well as overseeing original specials On Board Air Force One and Waking the Baby Mammoth.
"We certainly will miss Steve's significant contributions, but rest assured we will not miss a beat," Schiffman said in the memo. "We are fully committed to, and excited about, the shows in the pipeline, and in fact, I think our upfront programming slate is one of the strongest we have had in years."
