SANTA ANA ( – One Orange County zoo takes its monkey business very seriously when it comes to creating a haven for primates.

That’s because of an unusual contract put in place by the founder of the Santa Ana Zoo at Prentice Park.

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Under an old grant deed in 1949, Joseph Prentice agreed to give Santa Ana the 20 acres of land as long as the park bears his name and that “accommodations be provided for 50 monkeys” at all times or his heirs would take back the property.

“One out of every five animals we have is a monkey,” Zoo Director Kent Yamaguchi said.

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When the zoo opened in 1952, there were 50 monkeys. But in 2000, the monkey population dipped to 37.

At one point, one of Prentice’s heirs hired a lawyer threatening to take the property back. Fortunately, the monkey population grew again.

The current zoo director is always mindful of the magic 50-monkey number.

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“In fact, we maintained a little monkey buffer,” said Yamaguchi. “We make sure we’re above 55.” There are 58 right now. As a matter of fact, two of the primates are pregnant.