Sloth bear cubs born at Brookfield Zoo

Courtesy Sondra Katzen

Just in time for Mother’s Day, the Chicago Zoological Society, which manages Brookfield Zoo, is happy to announce the birth of two sloth bear cubs that were born on January 20. Until today, when they made their public debut, the cubs have been in a maternity den with their mom, Hani, 10, growing by leaps and bounds.

Sloth bears have a gestation period of six to seven months. (During the gestation there is a delayed implantation, meaning any fertilized eggs remain dormant in the uterus for a period of time.) At birth, the male and female cubs weighed less than one pound and could fit in the palm of a hand. Now at 3½ months old, they weigh approximately 10 to 20 pounds. Sloth bear cubs are born blind and rely on their mom for all their nutritional needs. They leave the den at about two to three months of age and remain with their mother for about two to three years.

Zoo guests will be able to witness one of the most intriguing behavioral traits of this species: a mother sloth bear carrying her young on her back. Rarely seen in other bear species, a cub riding on its mother’s back is a regular mode of family travel. Hani will continue to carry her cubs until they are about a third her size.

This is the first successful litter of sloth bears born at Brookfield Zoo. The species was exhibited at the zoo from 1936 through the early 1940s and has been part of its animal collection consistently from the late 1960s to the present. Hani, who is on loan to Brookfield Zoo from Capron Park Zoo, Attleboro, Mass., and her mate, Kartik, 3½, were paired together in 2011 based on a breeding recommendation from the Association of Zoos and Aquariums’ Species Survival Plan (SSP) for this species. An SSP is a cooperative population management and conservation program for select species in accredited AZA zoos and aquariums. Each SSP manages the breeding of a species to maintain a healthy and self-sustaining population that is both genetically diverse and demographically stable.

Sloth bears have a variety of characteristics that make them uniquely adapted to a diet of termites and ants. The bears have a mobile, flexible snout and lips that extend to form a tube. With this, they are able to suck up termites like a vacuum, making a slurping sound that can be heard from hundreds of feet away! This behavior is helped by a lack of upper front teeth. They are born with 42 teeth. However, once the permanent teeth grow in, only 40 remain, forming a gap in the front. To get access to bugs, they have curved, 3-inch-long claws for digging through dirt and termite mounds and into tree cavities. Sloth bears have a shaggy black coat and a light-colored, short-haired muzzle. A V-shaped cream-colored patch usually marks their chest.

Sloth bears are native to the forested regions of India, Sri Lanka, Nepal, and Bhutan in south Asia. They are accustomed to tropical climates even though they have a long, shaggy fur coat, which is thought to protect them from overheating and getting sunburned.

Sloth bears are listed as vulnerable by the International Union for Conservation of Nature’s Red List of Threatened Species. A total of fewer than 20,000 bears are thought to remain in the wild. There is evidence of wild populations having declined 30 to 49 percent in the last 30 years due to deforestation and poaching mainly for the medicinal market. Currently, there are 39 sloth bears exhibited at 18 North American zoos accredited by the Association of Zoos and Aquariums.

At Brookfield Zoo’s annual Bear Awareness Weekend on Saturday and Sunday, May 18 and 19, bear lovers of all ages can learn about the new sloth bear cubs, as well as the zoo’s other two species of bears—grizzly bears and polar bears—during Zoo Chats presented by Animal Programs staff. The informal talks will feature unique characteristics about each species, as well as facts about bears in the wild and the challenges they face.

The Chicago Zoological Society, which manages Brookfield Zoo, inspires conservation leadership by connecting people with wildlife and nature. The Chicago Zoological Society is a private nonprofit organization that operates Brookfield Zoo on land owned by the Forest Preserve District of Cook County. Open every day of the year, the zoo is located off First Avenue between the Stevenson (I-55) and Eisenhower (I-290) expressways and is also accessible via the Tri-State Tollway (I-294), Metra commuter line, CTA, and PACE bus service. For further information, visit www.CZS.org.