OMAHA, Neb. (AP) – After recent gorilla escapes at zoos in Boston and Dallas, the Henry Doorly Zoo is taking no chances.

The zoo tested out its new outdoor gorilla grottos by having rock climbers from the University of Nebraska at Omaha to try to climb out of them.

A few succeeded, including UNO senior Chris Rolling.

“There’s definitely a few things they’ve got to iron out,” Rolling said.

Because gorillas are more adept at climbing than humans, a successful climb by the students over the zoo enclosure’s imitation rock walls is considered a warning that the zoo’s gorillas could do so, too.

The students’ successes convinced zoo officials that some changes are in order. The zoo plans to shave off certain rock areas and fill in other crevices that could be used as holds for a foot or hand.

The new grotto is part of a $14 million dollar project and will open for gorillas in May.

In Boston, Little Joe, an adolescent gorilla, broke out of its enclosure at the Franklin Park Zoo last September, injuring a 2-year-old girl and a teenager before it was sedated and recaptured almost two hours later.

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