- endangered species a species that is in immediate danger of becoming extinct
- exterminate to get rid of by destroying completely
- extinction the death of all members of a species
- gregarious
Peggy and Nancy hit the road in search of adventure and discover a stampede of bison.
For thousands of years, bison (the North American buffalo) traveled widely over the western plains of North America, grazing on prairie grasses and finding drinking water with their acute sense of smell. These enormous animals can stand as tall as six feet and weigh up to 2,200 pounds.
Plains Indians hunted bison, using almost every part of the animal in some way. They ate the meat, fashioned weapons from bones, ground hoofs into glue, and made hides into ropes, blankets, clothing, and shelters. Even bison droppings served as a source of fuel. The Native Americans adapted their way of life to follow the bison herd as it randomly moved across its large home range.
Less than 200 years ago, over 60 million bison roamed the western grasslands. Settlers described herds so dense and covering such a large area that the ground shook and the prairie appeared to move as they ranged the grasslands. By the late 1800s, however, less than 1,000 bison survived.
Experts link the decline directly to the movement of cattle onto the plains. Cattlemen recognized the uniqueness of the plains country. Unlike eastern grasses, wild western grasses of the plains resisted drought and dried out on the open ground, providing nourishment for cattle even during winter. The cattlemen felt they faced one problem, however. Buffalo and Native Americans already occupied the grasslands. As long as they remained, the land couldn't be converted to pasture for cattle.
Because people thought the bison population was limitless, few laws protected the animals. Their size and gregarious (social) behavior made bison easy targets. From 1872 to 1874 alone, over three million were killed. Railroads and the army contracted with hunters like Buffalo Bill to supply buffalo meat for employees and soldiers. Professional hides men moved into the area, hoping to make big profits off the valuable hides, and homesteaders came to settle the new land. By the late 1800s, the animal was virtually eliminated from the western plains.
This dramatically affected Native Americans. Robbed of their livelihood, entire nations surrendered to the U.S. government. Most were driven onto reservations where they became totally dependent on the government.
Luckily, bison were never completely eradicated. Today, about 120,000 survive. Gone are the days when huge herds roamed the prairie. Instead, constrained by boundaries and surrounded by people, bison live a life quite different from that of earlier days.
tending to move in or form a
group with others of the same kind
Often we cannot determine the exact number in an animal population; instead, an estimate will do. How do scientists estimate animal populations? One method is by tagging a sample. Imagine that in a region, scientists can capture 90 bison and tag them to identify them later. The next year, in the same region, scientists capture 60 bison and find that 45 are tagged. Thus, three out of every four bison captured were tagged. Scientists then use a proportion to estimate the entire bison population for the region:
number of bison tagged (1st count)/population = 90/y number of bison tagged (2nd count)/population = 45/60 90/y = 45/60 To solve for y: 60 Yen 90 = 45y [Cross multiply] 5400 = 45y 5400/45 = 45y/45 [Divide both sides by 45] 120 = y Scientists could estimate that the area's bison population is 120. Now, it's your turn to predict a bison population!
Materials
total number tagged number tagged in 2nd sample ___________________ = ___________________________ predicted number of total number in 2nd sample population (y)
Questions
Many Native American stories focus on the relationship between humans and nature. Read some examples of these stories that center around bison. What lessons do these stories teach? What can we learn about the people who shared them?
During a stampede or flight, bison will walk, trot, bound, and gallop. Watch the Newton's Apple video, closely observing the bison movement. Analyze the gait of different individuals. Each gait is determined by the sequence in which the bison lifts and lowers its hoof.
Select an area in a state to begin a herd of bison. Determine the range quality--its carrying capacity and limiting factors. How many bison can be supported? What kind of vegetation will they need?
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