News Release

May 23, 2012

Contact: Sondra Katzen
Public Relations

Note: Photos of the bison calf and her mother at Brookfield Zoo may be downloaded at

Bison Calf Born at Brookfield Zoo
Symbol of the Chicago Zoological Society, Bison Represent a Conservation Success Story

Brookfield, Ill.—It is not exactly the sound of a stampede but more like the pitter-patter of little hooves that guests can hear at Brookfield Zoo’s Great Bear Wilderness exhibit with the addition of a bison calf born on May 16. The female calf marks the first birth of this species at Brookfield Zoo since the early 1970s.

The mother, Leotie, 3, arrived at Brookfield Zoo in 2009 from Wildlife Prairie State Park in Peoria to join the zoo’s bison herd, which also includes the calf’s father, Ron, 12; Judy, 12; Becky, 13; Drew, 13; and Lucy, 3. They can all be seen roaming their habitat at the Great Bear Wilderness exhibit, which opened in 2010.

The birth is a welcome addition considering the species was slaughtered to near extinction in the late 1800s. Bison were hunted for their meat and bones but primarily for their hides, which were made into clothing, machine belts, and rugs. Historically, tens of millions of bison traveled hundreds of miles over the same route through the Great Plains, shaping the land and enriching the soil. Remnants of their deeply worn paths are still visible. However, by the end of the 19th century, bison populations were eliminated over 98 percent of their range in the lower 48 states, resulting in fewer than 1,000 individuals remaining.

In 1905, conservationists Theodore Roosevelt and William Hornaday, the first director of Bronx Zoo co-founded the American Bison Society (ABS) at the Bronx Zoo, to help preserve this icon of America’s prairies. According to the Web site of the Wildlife Conservation Society, which manages Bronx Zoo, in 1907, staff sent 15 zoo-born bison by train to Oklahoma’s Wichita Mountains Wildlife Preserve to provide the core of a new herd that would help re-establish the species throughout the plains. Today, bison are making a comeback. Approximately 500,000 are managed on ranches and tribal lands, and about 20,000 live in protected parks and preserves such as Yellowstone National Park.
“The bison is the symbol of the Chicago Zoological Society (CZS), which manages Brookfield Zoo, because it is one of the first North American conservation success stories,” said Amy Roberts, curator of mammals for the Society. “We hope that when guests see this charismatic calf they will be inspired to take action in their everyday life to help ensure that these creatures and their natural habitats will flourish for future generations.”

The resurgence of the bison population is also thanks in part to the efforts of one of CZS’s conservation partners, the American Prairie Reserve (APR). The nonprofit organization, founded in 2001, is working with other government and conservation organizations to increase bison populations by protecting them and their habitat. APR is slowly purchasing private land that borders public land so that bison may freely roam once again. In partnership with the World Wildlife Fund, APR is assembling a multimillion-acre wildlife reserve to protect the species-rich grassland of northeastern Montana, where bison and other wildlife can thrive.

Some refer to bison as buffalo, which is theoretically inaccurate. True buffalo are native only to Asia and Africa. A member of the bovine family, bison are the largest land animal in North America. Males, called bulls, can stand 6 to 6.5 feet tall and weigh up to 2,000 pounds; females, or cows, are slightly shorter and can weigh between 800 and 1,000 pounds. Bison have a broad forehead and large head; short, curved horns; and a pronounced shoulder hump. They have a dark brown shaggy coat on their front legs, neck, and shoulders and shorter hair on the rest of the body. Their thick mane and coat protect them from severe winter weather; snow can cover their back without melting because they are so well insulated. The coat changes to a lighter color in spring, and as the weather warms they shed their winter coat, which is replaced with new hair in late spring.

Calves, which weigh between 40 and 70 pounds at birth, are usually born in late spring. Their coat is reddish at birth, and over a period of about 15 weeks it darkens to dark brown. They are able to stand within half an hour of their birth and can run after a few hours. Calves begin grazing when they are just shy of a week old but continue to nurse for several months.

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.

# # #