Sloth Atrium Opens April 15 at the Saint Louis Zoo

ST. LOUIS — The Saint Louis Zoo invites guests to slow down and look up at the new Sloth Atrium, a re-imagined, open-air habitat inside the historic Primate House. The new space provides an unobstructed view of Hoffman’s two-toed sloths, including Rolo, a one-year-old male making his Saint Louis Zoo debut.

Rolo arrived at the Zoo on March 28, from Zoo Atlanta, an Association of Zoos and Aquariums (AZA)-accredited institution, on recommendation from the AZA Hoffman’s two-toed sloth Species Survival Plan (SSP). He joins Pancakes, one of the Zoo’s resident females, in the newly renovated Sloth Atrium, which underwent extensive updates to create a habitat tailored for the arboreal species.

Starting Wednesday, April 15, the Sloth Atrium will be open daily during regular Zoo hours.

The Sloth Atrium

The Sloth Atrium is an open-air habitat designed for the latest animal care standards and uniquely suited to Rolo and Pancakes’ growth and enrichment needs. The space features misters, waterfalls, flowing streams and custom climbing structures. Built-in heat sources and UV lights replicate the warmth of Central and South American rainforests where sloths are found in the wild.

A moveable vine system allows animal care staff to routinely adjust the habitat, mimicking the constantly changing conditions of a tropical rainforest. The habitat was designed and built collaboratively by the Zoo’s animal care, facilities management and horticulture teams, with sloth safety and enrichment in mind.

“We're excited to revive the historic atrium for a new era,” said Helen Boostrom, Curator of Primates, Saint Louis Zoo. “Sloths have lived at the Primate House for many years, but the Sloth Atrium now provides over 1,300 square feet for the species, including a complex arboreal space. It’s a wonderful accomplishment to enhance our guests’ viewing experience and elevate animal care with one re-imagined habitat.”

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While sloths are not primates, the historic Primate House atrium offered an ideal environment for this tree-dwelling species. A 3 3/4-foot-high glass barrier surrounds the habitat, tall enough to keep Pancakes and Rolo safely inside without impacting guest views. The barrier also splits the habitat into two spaces, enabling Pancakes and Rolo to see, smell and interact with each other from a safe distance as they become acquainted. This process is a critical step in introducing two potential mates and traditionally takes place behind the scenes. Now, guests can observe early-stage introductions up close.

Later this year, guests will have the chance to step inside the Sloth Atrium during a bookable, behind-the-scenes tour that brings you face-to-face with a Hoffman’s two-toed sloth. Registration and pricing for the new sloth encounter will be announced soon.

Hoffman’s Two-Toed Sloths and Sloth Conservation

Hoffman’s two-toed sloths are part of the Megalonychidae family, which only includes one other species: Linnaeus’s two-toed sloths. They are native to the rainforests of Central and South America where they spend most of their lives suspended upside down in trees. Sloths’ exceptionally slow metabolism means digestion can take nearly a month, an adaptation that contributes to their famously slow pace.

Rolo came to Saint Louis Zoo through coordinated efforts with the AZA Hoffman’s two-toed sloth SSP, which works to ensure a healthy and genetically diverse population of sloths in North American, AZA-accredited zoos. Deforestation and widespread habitat destruction are the biggest threats to Hoffman’s two-toed sloths in the wild.

The Zoo’s third Hoffman’s two-toed sloth—13-year-old female Blondie—will not join Pancakes and Rolo at the Sloth Atrium. Blondie currently lives in a private habitat on the River’s Edge trail and will move to Henry A. Jubel Foundation Destination Discovery when the Zoo’s new experience for children and families opens later this year.

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