Less than a year after giving birth to baby Orolito, a pair of golden lion tamarins at Cleveland Metroparks Zoo welcomed two more little tufts of orange hair on December 27, 2010. The babies, whose sexes have yet to be determined, are clinging to mom, Brie, and dad, Cumin, and seem to be doing well. The Zoo is fortunate to have had three Golden Lion Tamarins (Leontopithecus rosalia) born in the last 10 months, as they are among the most endangered mammals on earth. Deforestation and habitat loss have relegated the golden lion tamarin to a small region in eastern Brazil. In fact, almost all golden lion tamarins found in U.S. zoos are actually considered to be on loan from the Brazilian government.

Photo credits: Jeanne DeBonis / Cleveland Metroparks Zoo

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Golden lion tamarins are part of a Species Survival Plan (SSP) organized by the Association of Zoos & Aquariums in which accredited member zoos and institutions collaborate to manage the population of endangered species. The Zoo has contributed 19 golden lion tamarin births to the SSP since 1997.

“Cleveland Metroparks Zoo continues to support the population management goals and conservation work of the golden lion tamarin SSP,” said Dr. Chris Kuhar, the Zoo’s curator of primates and small mammals. “We’re very happy with these infants as it not only helps grow the population, but it also allows Orolito to learn valuable parenting skills while he helps with the rearing of these two baby tamarins. We hope to continue the success we’ve had with this species in the future.”

Golden lion tamarins are brilliantly orange-colored monkeys that live in small family groups. The large amount of hair around the face resembles a lion’s mane and accounts for this subspecies’ name. All members of the group, including the adult males and adolescents, cooperate in raising the young. Golden lion tamarins are born weighing around 2 ounces, with their eyes open and all of their hair.

Adults typically weigh 22 to 25 ounces and grow between 13 and 16 inches long. The tamarin’s tail can reach up to 15 inches long.