Question: How many dead bison did biologists discovered on March 10, 2004?
About the article "Yellowstone National Park", section "Geysers and the hydrothermal system".

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The preservation of the wood bison in northern Canada was implied by the strict federal control of traditional Aboriginal hunting practices through the creation of a wildlife sanctuary.
The federal government proposed large scale ranching and breeding plans for bison herds.
Preservationist approaches to the bison in the north implied the assertion of federal power over the bison which had been under the control of Aboriginal hunters for generations.
There was no role for the human use of nature.
In 1952 and 1954, there was a shortage of mature adult male bison which resulted in the slaughtering of more female and young bison and caused conflict within the management.
CWS biologist Nick Novakowsi argued that the bison was declining due to slaughtering along with the effects of flooding.
This created conflict between the management at the Wood Buffalo Park and the federal government.
The park management did not see this as reducing the bison herd for stabilization, but instead described it as “mass murder.”The federal government’s goal of commercializing the bison throughout Canada undermined the need to provide inexpensive bison meat to the local population in northern Canada.
With new agreements with meatpackers in the south, combined with their prior commitment to the Hudson’s Bay Company and Indian Affairs, over nine hundred bison were slaughtered.
Through the agreement, the packing companies received top quality bison meat for low prices, while northern Canada got tough meat that was sold at higher prices.
CWS biologists feared that there was no scientific legitimacy to the slaughtering of the nine hundred bison, many which did not have tuberculosis.
In the winter of 1957- 1958, the testing and slaughtering program of the bison was established.
The conservation and commodification of bison are fundamentally contradictory goals.
In the late 1980s, there was a debate on the outbreak of tuberculosis and brucellosis at Wood Buffalo Park discussing whether the diseased bison should be replaced.
A committee was established in 1986 to discuss the possibilities of action and suggested: “maintenance of the status quo, fencing of the park boundary, a combination of fences and buffer zones near the park boundary and the complete eradication of the hybridized park bison with replacement by a disease-free hard of wood bison."
This caused a debate between Environment Canada, who was in favour of the eradication, and Wood Buffalo National Park staff, who opposed it.
The park staff argued that the risk of the diseased bison infecting cattle was overstated and that it was to justify using the bison for commercial purposes.
Due to the opposition the diseased bison were not slaughtered. 
The non-native but charismatic Catalina Island bison herd has existed for nearly a century.
A herd of American Bison roam, supposedly first imported to California's Catalina Island in 1924 for the silent film version of Zane Grey's Western tale, "The Vanishing American".
However, the 1925 version of "The Vanishing American" does not contain any bison whatsoever and shows no terrain that even remotely resembles Catalina, according to Jim Watson, columnist for the Catalina Islander newspaper.
Over the decades, the bison herd grew to as many as 600 individuals.
The population currently numbers approximately 150.
Biologists found that the American Bison of Santa Catalina Island are not pure bred; 45 percent have a domesticated cow as an ancestor.
The island's bison herd is maintained and monitored by the Catalina Island Conservancy.
Although the bison are not native to the island, they play an important role in the cultural fabric of Catalina.
Therefore, the Conservancy has no plans to remove all the animals from the island.
Controlling the bison population, however, remains important for Catalina's overall ecological health.
In the past, bison were routinely removed and sent to the mainland to auction.
In 2004, the Conservancy partnered with the Morongo Band of Mission Indians, the Tongva (thought to be Catalina's original inhabitants some 7,000 years ago), and the Lakota tribe on the Rosebud Reservation in South Dakota.
A hundred bison were relocated "home" to the Great Plains.
Recently however, another solution was implemented.
The Conservancy initiated a scientific study that determined that a herd of between 150 and 200 would be good for the bison, and ecologically sound for the island.
Beginning in 2009, the herd was given animal birth control to maintain the population at around 150 animals. 
The Wind Cave bison herd is considered to be genetically pure, meaning that there is no evidence of significant hybridization between these bison and cattle.
Most private and public bison herds in the United States are not genetically pure.
Genetic testing shows that there now appear to be some cattle genes present in approximately 95% of the bison surveyed in other areas.
Though the American bison (Species: "Bison bison") is not only a separate species, but a member of a separate genus from domestic cattle ("Bos primigenius"), they are genetically compatibile and American bison can interbreed freely with cattle.
Crossbreeds tend to look very much like purebred bison, so appearance is unreliable as a means of determining what is a purebred bison and what is a crossbred cow.
Many ranchers deliberately crossbred their bison with cattle, and it would also be expected that there could be some natural hybridization in areas where cattle and bison occur in the same range.
Since cattle and bison eat similar food and tolerate similar conditions, they have often been in the same range together in the past, and opportunity for cross breeding may have been common.
Most bison today are descendants of five herds that were conserved during the near-extinction event of the late 19th century.
These herds were subject to cattle crossbreeding experiments and as a result cattle genes are found throughout most bison populations.
In recent decades tests were developed to determine the source of mitochondrial DNA in cattle and bison, and it was found that most private 'buffalo' herds were actually crossbred with cattle, and even most state and federal buffalo herds had some cattle DNA.
With the advent of nuclear microsatellite DNA testing, the number of herds that contained cattle genes has increased.
Though approximately 500,000 bison exist on private ranches and in public herds, perhaps only 15,000 to 25,000 of these bison are pure and are not actually bison-cattle hybrids.
Significant public bison herds that do not appear to have hybridized domestic cattle genes are the Yellowstone Park bison herd, the Henry Mountains bison herd, which was started with bison taken from Yellowstone Park, the Wind Cave bison herd, and the Wood Buffalo National Park bison herd in Canada and herds derived from it.
A landmark study of bison genetics was undertaken by James Derr of Texas A&M University in an attempt to determine what genetic problems bison might face as they repopulate former areas.
It concluded that bison seem to be doing quite well, despite their apparent genetic bottleneck.
All of the state-owned bison herds tested contained animals with domestic cattle mitochondrial DNA, with the possible exception of the Henry Mountains bison herd of Utah.
Most national herds, except Wind Cave and Yellowstone, also appear to be hybridized.
As genetic testing improves, it may be discovered that almost all bison have some genetic inheritance from domestic cattle.
A separate study by Wilson and Strobeck, published in Genome, was done to define the relationships between different herds of bison in the United States and Canada, and to determine whether the bison at Wood Buffalo National Park in Canada and the Yellowstone Park bison herd were possibly separate subspecies, and not plains bison.
Some people had suggested that the Yellowstone Park bison were actually either of the 'athabascae' (wood buffalo) subspecies, or else that they were of an unspecified 'mountain' subspecies.
In the study, it was determined that the Wood Buffalo Park bison were actually cross breeds between plains bison and wood bison, but that their predominant genetic makeup was truly that of the expected "wood buffalo" (Bison bison athabascae).
However, the Yellowstone Park bison herd were pure plains bison ("Bison bison bison"), and not any of the other previously suggested subspecies.
This is significant for the Wind Cave bison herd, since this herd was founded, in part, with animals from the Yellowstone Park bison herd.
The bison in Wind Cave National park were also plains bison, as expected. 
The American bison ("Bison bison") once numbered in the millions, perhaps between 25 million and 60 million by some estimates, and they were possibly the most numerous large land animal on earth.
However, they were hunted to near extinction throughout North America by the late 1880s.
The Wind Cave bison herd was started with 14 bison from the New York Zoological Society and with six animals transplanted from the Yellowstone Park bison herd.
In addition, in the 1960s, one single bull bison was received from Theodore Roosevelt National Park.
The Yellowstone Park bison herd was the last free-ranging bison herd in the United States and the only place where they did not go locally extinct, so they have become at least part of the foundation stock for many other herds, including the Wind Cave bison herd.
The Wind Cave population has, in turn, served as the foundation stock for the Tallgrass Prairie bison herd in Kansas. 
John Dooly, owner of the island in 1893, with the help of William Glassman brought a herd of twelve bison to Antelope Island.
At the time American bison were nearly extinct in North America, having suffered years of over hunting and extermination during the settlement of the American West.
Biologists estimate that as many as 60 million bison roamed the western United States prior to the lands being settled by Anglo Americans.
These bison once inhabited the grasslands of North America in massive herds; their range stretched across most of what is now the United States, from Florida and New York in the east and south to the Texas/Mexico border and the Yukon Territory in Canada to the south and north and all the way west to the Pacific Coast.
The bison were an important resource for the native tribes of the western United States.
The United States Government knew this and began a campaign to rid the plains of the bison, thereby depriving the Native Americans of their most prized natural resource and making them dependent on handouts from the government.
Without the bison the Native Americans were forced to "seek peace".
Some conservationists saw that destroying the bison population was detrimental to the future of the nation and in 1874 Congress voted to stop the government sponsored slaughter.
By the 1890s approximately 800 bison remained.
Dooly purchased the bison after Glassman had failed to establish a bison preserve on the south shore of the Great Salt Lake.
Glassman had hope to attract tourists to the area with some of the few remaining bison in the United States at the time.
His venture failed and he was forced to sell some of the herd at auction.
Dooly bought the bison with the intention of supplementing his income with private bison hunts.
At approximately the same time a herd of elk was brought to the island.
The elk did not last very long due the island being a poor habitat for elk.
In 1993, 17 elk were reintroduced to the island with negative results; three drowned, three were never found, the remaining eleven survived.
However, due to the lack of a natural predator, the gray wolf, the bison thrived on the island and the herd rapidly increased in size.
The island was opened for bison hunts beginning in 1896.
The hunting of bison on the island was limited to those who could afford the $200 requested by Dooly and his ancestors.
Heavyweight boxing champion Jack Dempsey and 1920s sports writer Robert Edgren were just two of the celebrities that came to the island to shoot a bison.
Bison hunting continued on the island until 1926 when the final "Big Buffalo Hunt" eliminated all but a few of the bison.
Public sentiment changed during the 1920s and activists began to call for the protection of the herd on Antelope Island.
The hunt of 1926 was covered by "Time".
A herd of approximately 300-400 bison was culled to about 50 by a large group of hunters on horseback with modern rifles.
John Dooly had sold the herd to A. H. Leonard in 1924.
Leonard intended to sell the bison to zoos, but was not able to corral them.
He next tried to offer the island and the Antelope Island bison herd to the United States Department of the Interior.
Leonard had hoped that a national park would be established on the island therefore preserving the herd.
Time Magazine cites "Congressional apathy" for the lack of a land transfer.
Leonard was one again forced to change his business plan.
This time he wanted to expand the cattle ranching on the island and to do this the number of bison needed to be reduced.
Leonard announced a that a hunt would be held in the fall of 1926.
The hunt took place in November, but not without protests from around the nation.
The New York World and other newspapers of the day tried to arouse public sentiment against the hunt.
Utah governor George Dern received formal protests of the hunt from the American Humane Society, Massachusetts governor Alvan T. Fuller and Boston mayor Malcolm Nichols.
Governor Dern declined to prevent the hunt stating, "Antelope Island and the buffalo herd are privately owned."
The hunt took place with noted participants Ralph and Edward Ammerman of Scranton, Pennsylvania and big game hunter J. O. Beebe of Omaha, Nebraska.
The Antelope Island bison herd and the island remained in private hands until 1969 when the northern of the island were purchased by the state of Utah.
The southern end of the island was acquired in 1981, granting the entire herd protected status on Antelope Island State Park.
In 1986, park rangers saw the need to begin controlling the bison population to prevent overgrazing and disease.
The first "roundup" was held in 1987 and it has since become an annual event that brings in revenue by way of the sale of excess bison and tourist dollars brought in by spectators.