Critter of The Week # 11 : American Bison

Few other animals share quite the history like the American bison. They are the largest land animal in North America, with the largest males reaching 6 feet at the shoulder and weighing up to 2,000 pounds. Their story is weaved into the fabric of the United States' history just as much as the people who formed it. They took center stage on many different occasions; from becoming the Sioux's greatest ally in war, to becoming an obstacle to the march of civilization. They were part of one of the greatest, if not the most jaw-dropping wildlife spectacle man has ever recorded. No other large animal roamed in such mind-boggling numbers as the bison, not even the ungulates of Africa or anywhere else in recorded history.
There were 30 times as many bison as there are wildebeest today.
First-hand accounts often were at a loss for words when describing the herds, as there was nothing else like it coming from their homelands. The bison's story is a tumultuous and tragic one, but also one of triumph. In less than 50 years, they were driven to almost complete extinction but the strongest, smartest, and fastest held on. And through the actions of a few visionary people, these majestic animals survive today to be nominated as America's national mammal, which is a title that is well-deserved and hard-earned.
No one is really sure just how large the giant herds of bison were when they were discovered by Europeans but experts estimate 30 million was a realistic guess. More historians agree, the main reason the "new world" or what would later become the United States, was so rich in natural resources was due to European diseases that wiped out 80-90% of the native peoples.
 Prior to that, the aboriginal population was estimated to be around 20 million. When European diseases arrived in the 1500's and later, it left entire civilizations empty. This tragedy gave America's wildlife an opportunity to recover like nowhere else on earth.
From 1500 until around 1750, all animals on the continent began expanding their ranges and thriving. 
Flocks of passenger pigeons were so large, they would blot out the sun for hours when flying overhead. The great bison herds reached their peak at what scientists estimate to be around 30 million animals. To put that into perspective, the wildebeest herds we have all grown up watching on TV in Africa, only number 1 million. Packs of white wolves 100 members strong were constantly following the buffalo looking for the sick, injured, or weak.
The land looked wild and unspoiled, and was full of life. In this 1800's painting, the artist depicts what looks like a never ending flock of passenger pigeons.
The journals of Lewis and Clark described western herds “so numerous” that they “darkened the whole plains.”
Many firsthand accounts said you could hear the herds coming before you saw them. If they were running or stampeding, the sound was described as a constant rolling thunder in the distance. In drier times of the year, large dust clouds could be seen miles away as the herds moved. The sheer numbers of living beings on the continent was staggering. It was the last time man glimpsed a true wilderness at its peak anywhere on the planet. 
Being such large animals, the bison shaped the land and helped make the prairies into the productive fields they are today. They fertilized the soil with their dung and they also formed shallow pools with buffalo wallows, or depressions in the earth where hundreds of thousands of bison would dust bathe. Eventually, these depressions would fill with water and support frogs, salamanders, and provide water for thirsty animals. This buffalo wallow was photographed in 1897 and was one of thousands across the plains.
Through firsthand accounts, we have learned that the bison of 1750 were very different than the bison we have today. Not so much in terms of appearance, but in terms of genetics, and even behavior. 
When bison encounters were first described, the animals were slow, almost docile, and if they sensed danger, they would run towards it. 
This seems to defy logic but before man and after the population reduction of Native Americans, the main enemy of bison were wolves and bears. Bison are large and formidable, and when a million are running straight at you, it is sure to scare. So this strategy worked perfect for their normal predators, but proved a major flaw against man. 
Before horses were brought by the Spanish, Native Americans hunted bison mainly by driving them off of cliffs. They would single out a small group and funnel them towards a cliff edge and eventually driving them over.  Once horses arrived, they quickly tamed the new arrivals and became formidable hunters. They would ride alongside the bison with large spears or arrows and take them down.
Once caught, the Sioux and many other tribes used every part of the bison, and before European settlers, nothing would go to waste. Their fat and dried meat made one of the best survival foods of the time. pemmican.  Some of their bones were made into jewelry or weapons and their hides provided amazing waterproof shelter and clothing.
It wasn't until after 1850 that the bison's existence was in peril. When European settlers, farmers, fur traders, hide hunters, and sport hunters came into the region, they hunted and killed huge numbers of them; oftentimes leaving the bodies to waste away on the plains. When the railroads came in, the mass extermination began. It split the great herd into two, the north and south herd, and eventually the southern herd was exterminated.
When General Sherman officially encouraged the shooting of bison to weaken the Native American's supplies, soldiers joined the extermination.
Their hides were used to make belts to help power machinery used during the industrial revolution, and to make bison coats, hats, and even rugs.
Flyers were seen advertising shooting bison for fun from passing trains, leaving the bodies to waste. The cattle guard we see on the front of old trains was originally designed to ram bison as they pushed through the giant herds. Bison were often only killed for their tongues or hides by both Europeans and later even by natives who would trade with the new arrivals. Bison were seen by most to be obstacles to progress, competition for grazing, and a nuisance. 
It seemed that we had officially waged war on the bison, and they didn't even know it.
When Europeans first arrived, the bison were trusting and almost laid-back. 
By 1886, they were much different. In less than 50 years, man exterminated the nation's most numerous large mammal. From 30 million in 1850 to an estimated 300 animals in 1886. One newspaper at the time called it  “a rate of extermination that is almost incalculable and one of which the mind can have no just conception.” The photo below puts into perspective the scale of extermination. 
It was in 1886 that perhaps the bison's new best friend arrived, a zoologist and taxidermist named William T. Hornaday. Hornaday was assigned by the National Museum to capture a few bison for a taxidermy display of the animals. It seemed ironic to hunt an animal on the verge of extinction, but it was a way to preserve their legacy in case they actually went extinct.
This was when Hornaday met the new kind of bison.
He described how the bison of the past, who would ran towards danger were long gone. Now, the only bison left were the ones who figured out how to escape man's rifle, horses, and arrows. These were the smartest, fastest, and strongest. Oftentimes at the first sight of the men on horseback, the bison would jump up in a frenzy and be gone over the horizon. These bison were strong, fit, and could run just as fast as a horse and were high strung, nervous animals. Their senses were keen and heightened at all times as their very lives depended on it. 
Hornaday got his specimens, which can still be seen today in a museum in Montana. 
He would later give up his taxidermy career and have a major change of heart. He became one of America's first major conservationists and became friends with Teddy Roosevelt. He created the American Bison Society, which started breeding bison and transporting them around the plains. 
This image taken from the National Park Services archive shows just a few members of the last remaining bison. Images of bison at the time were very rare. The extermination was so fast that very few people took the time to take pictures.
Once the bison were finally protected, fewer than 300 remained, but they survived and perhaps the most famous herd was the Yellowstone herd, which only had 23 animals. This group has now multiplied into the 3,000 range or more that we have in the park today. 
Their story taught us many great lessons that we can pass onto future generations about conservation, respecting nature, and cherishing the riches that we have now. The bison helped pave the way to the formation of many of America's national parks and was the beginning of the conservation movement. 
Today, bison number 300,000 and growing.  One percent of that is estimated to be the genetically pure bison Hornanday saw in 1886. All of the rest have been cross-bred with cattle to produce a better meat animal that is more laid back yet looks almost the same as a bison.
The real bison, the wild and free ones, are seen only in Yellowstone National Park. So next time you go to Yellowstone, marvel at the fact this is the only place in the U.S. where bison have been since the ice age.
These are the descendants of the fastest, toughest, and smartest bison from those days. It is the only place they face their natural predators, bears and wolves. 

Scientific Classification :

Kingdom : Animalia

Phylum : Chordata

Class : Mammalia

Order : Artiodactyla

Family : Bovidae

Genus: Bison

Number of Different Species : 1

Plains Bison : Bison bison bison

Conservation Status : 

Near threatened : 

May be considered threatened with extinction in the near future, although it does not currently qualify for the threatened status.

Range :

Historically, the plain's bison ranged from Southern Texas and Northern Mexico to Southern Canada and parts of the Eastern United States. It is believed they were still expanding their range when Europeans arrived. Today, they are limited to just a few parks and reserves like Yellowstone National Park. 

Habitat : 

Bison roamed on the short, mixed, and tall-grass prairies of the United States, Canada, and parts of Mexico. Their stronghold was the mixed grass prairies of Montana, Kansas, Northern Texas, and Nebraska. 

Diet  :

Believe it or not, bison are related to cows, sheep, and goats! They are herbivores and primarily eat grass. Historically, they grazed on the prairie grasses of the Midwestern United States. Some of the species of grass include big and little bluestem, aptly named buffalograss and many others. America's grasslands were unique because unlike other grasslands around the world, which have poor quality soil, the great plains of the U.S. have some of the most fertile soils on earth. This was in part due to the roots of these mixed grasses and the manure from bison! Some roots were 2 feet deep or more and made them incredibly drought, fire, and grazing resistant.


Bison have an incredibly efficient digestive tract much like cows do. It is divided into 4 chambers, which the diagram below shows just how this whole system works.


Bison played a key role in the entire prairie ecosystem. The huge herds would fertilize the soil with their dung. Their giant bodies fed thousands of other animals including wolves, coyotes, vultures, ravens, foxes and many more. They created wallows that would fill with water and support frogs, salamanders, turtles and provide water for many other animals.

Also like cows, bison do not have front teeth on the top of their mouth. They have developed a fleshy pad that the bottom teeth press against to grab tufts of grass in a very efficient manner.


They also graze with less impact on the land than cattle and can be raised with less input than what is needed to keep cattle alive. In the winter, they use their strong wooly snouts to shovel through the snow to continue grazing all year long. It's something cattle have a very hard time doing and oftentimes perish without supplemental feeding.  


Reproduction :

Female bison and young calves usually stay in small maternal herds. When males mature, they separate into bachelor herds. Larger bulls will begin fighting for females and mating rights so much so that this time of year, they can lose hundreds of pounds.


The winning dominant bulls will have mating right with a group of females. Once the male sees a female he likes, he will bellow and if she does it in return, it is usually a match.


The first 2-3 weeks of the breeding season, the dominant males get first pick, then the subordinate males can come in later.  


Once pregnant, the female carries the developing calf for 9 1/2 months, and goes to a secluded place to give birth. Once born, within an hour or less, the calf can run and walk with the herd. They are a reddish brown color when born and range from 30-60 pounds at birth. She will nurse them for 8-9 months. 

Relationship With Humans :

Bison today still have a mixed relationship with humans. Out of the 300,000 or so that exist, almost all of those are raised as livestock for meat. Those same ones raised as food, have cattle genes in them.


The biggest challenge they face today is roaming outside of the Yellowstone Park. Cattle ranchers claim bison carry a deadly disease that causes abortions in cattle called brucellosis. This was a disease brought from Europe that bison never carried until modern times and have never transmitted to cattle.


This pressure from ranchers has forced the government to round up some bison every few years and kill them.


There are an increasing number of people who want to see the bison restored to their former range and a growing movement is forming to help make that happen and allow them to expand outside the park.


Many tribes have also convinced the government to give them genetically pure bison for their own traditional herds.


Finally in 2016, the bison was named the official mammal of the United States.


If we can convince cattle ranchers to welcome bison on their land and let them expand elsewhere, then maybe in the next 50 years, we can see a small glimpse at what it may have been like to see these magnificent and powerful animals on the great frontier.