Disney movie studio boss Rich Ross stepped down on Friday, taking the fall for at least a couple of over-budgeted bombs as Hollywood shies away from taking risks on big blockbusters.

His resignation comes after two years in a row of nasty March surprises, ironically both having to do with the Red Planet. Last year it was "Mars Needs Moms," a creepy animated movie that lost $70 million. This year, it was "John Carter," a sci-fi action movie set on Mars that resulted in a $200 million loss for Disney.

Ross, 50, said in a memo to staff that he no longer believed his role as chairman of Walt Disney Studios was "the right professional fit."

The move was not surprising to analysts, coming a few months after studio marketing chief MT Carney also departed because of a string of lackluster releases.

Disney CEO Bob Iger, who said last summer that big-budget movies were getting "increasingly more risky," thanked Ross for his years of service.

The Walt Disney Co.'s stock rose 27 cents to close Friday at $42.35.

Disney's most successful movies recently have been made by studios it has bought, including "Toy Story" maker Pixar, which releases "Brave" in June, and Marvel, which will release the much-buzzed "The Avengers" overseas next week.

Under the Touchstone brand, Disney also distributes movies made by Steven Spielberg's DreamWorks production company, including "War Horse."at the studio is seen as crucial for the company, because movies launch characters that are developed into Disney toys, theme park rides, books and video games. For example, "Cars Land," an attraction based on the Pixar movies, will open at Disney California Adventure in June.

"For Disney, it feeds a lot bigger value chain," Sanford C. Bernstein analyst Todd Juenger said. "This is a more significant move for investors of Disney than it would be at other companies."

Although some of Ross's troubles stemmed from films put into production by his predecessor, Dick Cook, analysts said his inability to prevent big losses was what led to his exit.

"At some level he takes responsibility for not fixing them or shutting them down," Needham & Co. equity analyst Laura Martin said. "They need to lower the risk of entry and build franchise films from that base. Not go all in, hoping it works out."

Part of the estimated $250 million budget on "John Carter" can be attributed to the notion that the movie could become a multi-part series, as it was based on a trove of books by the late Edgar Rice Burroughs. The series began with "A Princess of Mars" in 1917 and carried through to the posthumously published "John Carter of Mars" in 1964.

The movie starring Taylor Kitsch had a budget that rivaled what 20th Century Fox spent on "Avatar."

But "John Carter" made only $269 million at box offices worldwide while "Avatar" took in $2.8 billion. After splits with theater owners and marketing expenses, Disney has said "John Carter" would cause a studio-wide loss of $80 million to $120 million in the January-March quarter.

Ross had taken the job just two and a half years ago with a mission to cut costs and develop new hits. He had brought "High School Musical" and "Hannah Montana" to TV audiences when he headed Disney Channels Worldwide.

Ross spent much of his early tenure at the studio cutting costs and canceling projects that weren't seen as important to the Disney brand.

He shut down the San Francisco-area motion-capture facility used to digitally animate Jim Carrey's Scrooge character in "A Christmas Carol," sold the award-winning Miramax label to outside investors, and cut such movies as "20,000 Leagues Under the Sea" and "Wild Hogs 2" from the development slate. Last year, he suspended production on "The Lone Ranger," starring Johnny Depp, until its budget was trimmed.

But those efforts were overshadowed by movies that were released but failed to excite big audiences, including "Prince of Persia," "Prom," "Secretariat" and even "Winnie the Pooh."

Ross told staff in a memo Friday that "the best people need to be in the right jobs, in roles they are passionate about, doing work that leverages the full range of their abilities."

"I no longer believe the chairman role is the right professional fit for me."

Iger wished him well in a statement.

"Rich Ross's creative instincts, business acumen and personal integrity have driven results in key businesses for Disney," Iger said. "I appreciate his countless contributions throughout his entire career."

Ross's resignation is effective immediately. Disney did not name a successor.

A couple possible candidates for elevation at the studio are John Lasseter and Ed Catmull, who together built Pixar from a computer imaging company into an animated movie powerhouse. After Disney's acquisition in 2006, the men have top jobs overseeing animated movies at Pixar and Disney.

The men have helped Disney's animated films move "in the right direction," according to Don Peri, the author of a couple books on Disney animators including "Working with Disney." He declined to speculate on whether they would make good studio heads.

娱乐快讯：北京时间4月21日消息，据外媒报道，由于投巨资制作的3D科幻电影《异星战场》(John Carter)票房惨败，迪士尼公司(DIS)旗下影视制作部门迪士尼制片厂(Walt Disney Studios)主席里奇·罗斯(Rich Ross)周五宣布辞职。

罗斯是两年半之前接替迪克·库克(Dick Cook)出任迪士尼制片厂主席的，身上背负着削减成本和开发新的热门电影的使命。不过，尽管做出了巨大的重组努力，他仍未能扭转该影视制作公司的亏损。

一个月前，迪士尼预计《异星战场》将给公司带来约2亿美元的亏损。这部电影的制作成本为2.50亿美元，与20世纪福克斯公司的《阿凡达》相同，但全球票房收入只有2.69亿美元。在与影院运营商分账并扣除营销开支后，迪士尼估计这部电影将导致其制片厂第一季度亏损8000万~1.20亿美元。

罗斯周五在致员工的一份备忘录中表示，迪士尼制片厂主席的职位已不再适合他。

罗斯的辞职将即刻生效，迪士尼未宣布他的继任人选。