by John Nuño

SAN FRANCISCO (KCBS) — The doors in the San Francisco Zoo’s gorilla enclosure had a history of mechanical problems long before one of them fatally crushed a 16-month female gorilla named Kabibe earlier this month, according to a newspaper investigation.

The San Francisco Chronicle obtained records revealing that, in 2010, Kabibe’s older brother had his hand caught in the same door that killed his sister on Nov. 7.

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In the summer of 2012, another adult gorilla had her hand pinched by another door and last March, that same door had to be pried open with a crowbar after it jammed shut.

Zoo Executive director Tanya Peterson, said the keeper who operated the door that closed on Kabibe failed to follow protocol by not keeping her hand on an emergency stop button.

Five zookeepers told the paper, however, that in addition to the mechanical problems with the door, the layout of the gorilla’s enclosure is flawed and that inadequate staffing is threatening safety.

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“It was a freak accident,” Corey Hallman, an animal keepers told the Chronicle, “But with a workplace that takes safety and keeper input more seriously, it could have been prevented.”

On Nov. 6, 2013, zoo keeper Eva Soni sent an email to management citing safety concerns.

“I am all for more safety and I think the buddy system is a good idea, it just needs to be done right,” she wrote. “The only long-term, safe and feasible option I can think of is adding another ‘ape keeper’ to our staff who will assist both chimps and gorillas.”

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While zoo officials did not comment on the Chronicle’s interviews with the animal keepers, they maintain that a U.S. Department of Agriculture inspection in January found no problems with the exhibit.