Two new members, who are little in terms of both age and size, have arrived at the Henry Vilas Zoo.

The zoo announced Tuesday the adoption of a set of Geoffroy’s Marmosets, an endangered species of monkey rare in zoos around the world.

According to a statement released by the zoo, Vilas received the twin marmosets through the Species Survival Plan, a program launched among zoos to help conserve endangered species.

“We called the program and said we were interested,” curator Jeff Stafford said. “The mother [of the twins] was sent to us from San Diego, and the father was from Nebraska.”

Stafford said the Species Survival Plan would evaluate the relationship between the mother and father and determine whether they would be suitable to give birth to baby marmosets.

He said Brazil, the country the marmosets are originally from, would retain ownership of the animals. He added marmosets can only be found in around 20 zoos in the U.S.

Stafford said the zoo hopes more visitors will be interested in seeing the new members but emphasized boosting traffic is not the main reason behind bringing the endangered species into the zoo.

“They are very, very cute,” he said. “But that’s not why we are doing it. We are doing it so that we can help these animals in the wild by stimulating interests.”

County Executive Joe Parisi said in a statement that the twin marmosets are a great new addition to the county’s zoo family and encouraged county residents to stop by the zoo and visit them.

“Visiting these fascinating animals in their warm, indoor habitat can be a great break during this busy holiday season,” he said.

Stafford added that he hopes the marmosets inspire conservation efforts.

“When people come, they see these unique animals and how cool they are. We hope that they will be more motivated to do some conservation things,” Stafford said. “Keeping [endangered] populations up is also one of the things that the zoo does for the wild.”

Support for the zoo and the animals mainly comes from donations and sales of gifts and food within the zoo.

Apart from donations, visitors can also support the zoo through buying memberships and joining the Friends of the Zoo program. This December, the zoo launched a membership drive. Benefits of joining include receiving discounts when making gift shop purchases.

Lynn Pawelski, associate director of the Friends of the Zoo program, said this is the zoo’s first time launching this kind of promotion. She added there was a similar promotion in November, and visitors’ responses had been very positive.

Pawelski added the zoo is offering a low-rate membership for students interested in supporting the zoo and joining.