plants The sun beats down on their shaggy brown capes of fur When the herd has taken its fill it is time to rest Most of the bison lie in the grass They make deep sighs as they fold their legs beneath their large bodies But two bulls A Big Influence Bison had a large effect on their habitat They were the largest herbivore on the plains When they were removed from the plains many other plants and animals also disappeared Now groups are working to save the plains The bison are an important part of this work Bison droppings contain plant seeds Their hooves mix the soil and bury these seeds In 2005 bison were brought back to Grasslands National Park It is on the Montana and Saskatchewan border Bison have changed the habitat in a good way Many different native plants are once again growing in areas where there were few before are restless They lower their heads and snort Their fury grows Who is strongest They paw the ground and charge Their large horns hook as they battle head to head Threats to Bison Once grasslands covered one third of North
Native Americans used bison hide to make clothing items such as gloves America These lands were home to more than 30 million bison They were a source of food and materials for native peoples In the 1800s the sound of bison faded Settlers and sport hunters began killing bison faster than bison could be born Bison lost their habitat to farming towns and railroads By the late 1800s there were only 1 091 bison left
Some people saw that bison were in danger and they took action Ranchers caught bison and raised them on their land Later governments in the United States and Canada set aside land to protect them Over time bison GPS A few parks use global positioning system GPS radio collars to track their bison GPS uses satellite technology to provide precise location information It tells researchers the bison's food preferences Vets at Prince Albert National Park in Canada make sure that their bison are safe while collars are attached to them First they work with a helicopter pilot to locate the bison The vet darts the bison with a special gun The dart holds drugs that make the bison fall sleep While the bison is asleep the vet checks its health The bison is fitted with a GPS collar The collar lasts approximately two years until the battery dies herds grew But there are still reasons to be concerned about the bison As of 2016 500 000 bison belonged to privately owned herds However these bison are not raised to conserve the species They are raised for their meat and hides
Bison once roamed the Great Plains Today their range is restricted to parks and reserves There are only approximately 4 000 bison in public herds Some ranchers believe that these public herds carry disease They fear that bison could make their cattle ill But most scientists believe that there is no threat from wild bison to cattle Still most public herds are kept behind fences Bison cannot maintain the grassland ecosystem while fenced in Scientists fear that in time bison behavior may change Wild bison held behind fences may begin to act more like livestock
