L.A. Zoo's new hippo calf surprises staff; Mother was on birth control

Why Zoo's New Hippo Calf Was a Total Surprise
Why Zoo's New Hippo Calf Was a Total Surprise

The L.A. Zoo welcomed a surprise addition to its hippo habitat Friday, but fans will have to wait a bit to find out the sex of the baby.

In an effort to maintain the all-important mother-child bond, the zoo's staff hasn't gotten close enough to determine the calf's sex.

The newborn, which has not been named, is the first hippopotamus calf at the zoo in 26 years and was a "happy surprise," especially because the 10-year-old mother, Mara, was on birth control, officials said.

The zoo had some advanced warning when she started to put on weight, but the staff was unable to do a pregnancy test. Even so, the staff's guess of a November birth wasn't far off.

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