Bison on the Fort Belknap Indian Community in Montana. Photo by Bronc Speak Thunder / Facebook

Tests are underway to determine why 19 bison that were transferred from Yellowstone National Park to the Fort Belknap Indian Community died.

The animals were found dead during and after the July 4 weekend. They came from genetically-pure group of bison that the tribe accepted from Yellowstone in 2012.

"This knocks us back several years," Bronc Speak Thunder, the tribe's bison program manager, told The Great Falls Tribune. "You lose 90 percent of your production; that's a pretty big blow."

The tribe has other bison but the deaths represent a significant portion of the genetically-pure herd. Only 38 of those animals remain, Speak Thunder told the paper.

The state is now conducting tests to determine the cause of death. Results might not be available for 10 days or longer, the paper reported.

Get the Story:
No cause of death for 19 Fort Belknap bison (The Great Falls Tribune 7/29)
18 dead bison found in Fort Belknap pasture (The Great Falls Tribune 7/14)
Anthrax not suspected in Fort Belknap bison deaths (The Great Falls Tribune 7/14)

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Ryan Dreveskracht: Another threat to bison and tribal rights (05/13)
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