Sloth Atrium Opens at the Saint Louis Zoo

The new Sloth Atrium, a re-imagined, open-air habitat inside the historic Primate House, opens on April 15. It provides unobstructed views of the two-toed sloths, including Rolo, a one-year-old making his debut at the Saint Louis Zoo.

Rolo joins Pancake, one of the Zoo's resident females. 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.

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.

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

Learn more at stlzoo.org.