A tiny, black monkey named April, stolen earlier this week from Cherry Brook Zoo in Saint John, N.B., has been recovered safe and sound by police following an anonymous phone tip.

"Relieved doesn't describe (the feeling)," Lynda Collrin, director of zoo development, told CTV Newsnet Friday.

April, a rare callimico, a species also known as Goeldi's monkeys, is from the Amazon region of South America. April is part of a vital breeding program trying to keep the primate species from extinction.

At nine months old, April weighs an estimated half a kilogram.

April was stolen Wednesday morning when someone jumped a fence, kicked in a door to the monkey's cage, that she shared with her family.

Following the phone tip, April was found by police behind a gas station Thursday night in a blue Rubbermaid tote, which was sealed, with holes cut through the top, Saint John Police Sgt. Pat Bonner said.

Police did not open the box there, fearing the monkey could escape, and notified zoo officials.

Zoo officials kept April overnight, feed her the proper food and pronounced her ready to join her family Friday.

Due to the monkey being away for a period of time, there was a concern that animal could be rejected by her family.

"Fortunately, she went back down into the enclosure (with her family)," Collrin said.

Added zoo keeper Shyanne Polley: "The family is very happy, they are as happy as we are."

There are "definitely" going to be changes to the zoo's security, Collrin said. But she added that this was the first major security breach at the zoo.

There was a note left with the monkey, Collrin said, but its content is being withheld by police at this time.

Police continue to search for those behind the incident.

"They didn't just take a monkey. They took a unique (animal) that is going to help save her species from extinction," Collrin said.

With a report from CTV Atlantic's Dina Bartolacci