Southeast Asia


Dense tropical and subtropical forest

Small but mighty

The sun bear is the smallest of the world's eight bear species, about half the size of the American black bear. Its common name comes from the white or yellowish crescent marking on its chest, which many people think looks like the rising or setting sun. Each bear’s crest is individual—like fingerprints.

The sun bear’s jaws provide a powerful bite force and are often ued to tear into trees to get at the burrowing insects beneath the bark. They have a distinctive pigeon-toed walk, an adaptation to their arboreal lifestyle. Like other bears, sun bears have an incredible sense of smell, thought to be several thousand times better than that of humans.

Tree, sweet tree

In the Malay language, the sun bear is called basindo nan tenggil, which means “he who likes to sit high.” It certainly lives up to that reputation! The sun bear likes to make its home in the branches of trees. Its small size, four-inch-long (10 centimeters) claws, and large paws with hairless soles help the little bear move about with ease high up in trees.

Those branches also make a nice place to build a nest for resting or sunbathing during the day, although in areas undisturbed by humans, sun bears are more likely to rest on the ground. Their eyes are more forward-facing than those of longer-snouted bears like polar bears, which is another adaptation thought to aid in climbing.

“Dog-face bear,” “Malay bear,” and “honey bear” are common nicknames for the sun bear.
Sun bears do not hibernate like cold-weather bears, probably because their tropical habitat provides food sources year-round.
Small sun bear, black bear, and sloth bear populations have been found in eastern India, making this area the only place where the three species of bears are known to coexist today.

Our first sun bears
Our very first sun bear arrived in 1928—quite an accomplishment for a young zoo in a small city to obtain such a rare bear! In 1935, two more arrived. On New Year’s Eve, 1938, we welcomed our first Malayan sun bear cub; sadly, it did not survive long. However, more cubs were born in the early 1940s. It was a challenge to keep up with these clever bears; a 1940 article from our member magazine, ZOONOOZ, recalls:

“We gave them a cement tree, which they proceeded to break to pieces with teeth and claws. Before the first week was over they had all of the cement broken off the tree and the branches, made of strong rods of reinforcement iron, bent all out of shape, and the metal lath upon which the cement gunnite had been shot hanging in shreds. Finally we took them out and built a tree with reinforced pipes for limbs and the heaviest, hardest cement possible to obtain sprayed on very, very thick. They put this tree through every test, but it has stood and how they love to go up and down it."

Celebrity bears
In 1965, a Malayan sun bear named Boo Boo was honorably “discharged” from the United States Navy and donated to the Zoo’s Children’s Zoo after serving more than six months as the mascot to the Seabees of MCB Ten in the fighting zone of Vietnam. Boo Boo held the distinction of being one of the few animals to receive dental care from a navy dentist; apparently, the Seabees fed her a lot of sweets, causing dental problems. Another “celebrity” sun bear at that time was Josephine, who had been the mascot of the University of California, Los Angeles’ football team in 1961.

When Sun Bear Forest opened at the Zoo in 1989, five young Malayan sun bears quickly, and true to form, tore up their new home, ripping out grass, trees, and anything else they could find. Zoo architects and horticulturists again had to redesign the exhibit to make it more "bear proof." Still, the new exhibit was a success, as we welcomed the birth of Stanley later that year.

Our bears today
Our Zoo is currently home to two Bornean sun bears, Marcella and Francis. As the only successfully reproducing female Bornean sun bear in the U.S., Marcella is a great ambassador for sun bear conservation. Her first cub, Danum, was born in 2004, the first Bornean sun bear to be born in North America. Second son Bulan was born in 2006, and in 2008, Marcella had twins Pagi and Palu. Because sun bears are so hard to find in the wild, Marcella and her babies allowed researchers and keepers the rare chance to study mother/cub interactions. All four of Marcella’s offspring have moved to other zoos as part of the Species Survival Plan for sun bears.

Sun bears are a species vulnerable to extinction. It is unknown how many are left in the wild, since their secretive nature makes them hard to find, and few studies have focused on these animals. This lack of data currently prevents them from being listed as endangered; however, wild sun bear populations are believed to be dwindling rapidly, due mainly to habitat loss from farming and logging, poaching (both for meat and use in medicines), and even the pet trade. Their appetite for oil palm and other commercial crops has led to a lot of trouble between sun bears and humans, and wild sun bears are walking a survival tightrope.

The population of this rare bear is thought to have declined more than 30 percent in the last 30 years. Although it is illegal to kill sun bears, laws protecting them are rarely enforced.

San Diego Zoo Global, through past participation in the Bornean Sun Bear Species Survival Plan and current efforts with zoos worldwide, is certainly doing its part to help these petite and fun-loving bears. We also collaborate with the Bornean Sun Bear Conservation Centre (BSBCC) in Sabah, Borneo. BSBCC serves as a rescue and rehabilitation facility for orphaned and injured sun bears.

We are excited about developing our partnership into a research opportunity that will aid in the conservation of the smallest bear on Earth and could lend insight into this bear’s biology. We know from our past work, for example, that sun bear mothers and panda mothers are very similar in their attentive maternal-care styles, and both pandas and sun bears differ from the less active hibernating bears like brown and black bears. What other similarities and differences between the bear species will we find?