Annual bison roundup has become a widely anticipated spectacle.

The Annual Bison Roundup began bright and early Oct. 4 in Moiese. What was never intended as a public event has become one of the area's most anticipated spectacles. One of the last great vestiges of the Old West was the roundup from a range area covering over 18,000 acres. The purpose was to thin the herd and monitor bison health.

Set up in 1908 to help increase the size of bison herds, which were on the brink of extinction, The National Bison Range has, over almost 100 years, grown public herds to between 20,000 and 25,000 head.

Monday's goal was to whittle the bison population down to a manageable 380 for the winter. Reducing the herd's size is necessary to protect grassland forage upon which the bison and the other wildlife in the range depend.

With flying dust and thundering hooves, an experienced staff of horseback riders from the Bison Range began cutting 20 to 30 of the adult bison from the herd. Working bison is nothing like working cattle, and only the best of the best qualify for the job.

These animals are known to be strong, temperamental and oftentimes dangerous.

Again and again the smaller herd was hazed into even smaller corrals until the behemoths were prodded onto the electronic scales and weighed. The scales are used to provide data used for monitoring herd condition. Blood was drawn for genetic testing. Keeping well out of harm's way, staffers worked from the bison's tail.

Calves had their own scale and squeeze chute. They were branded so range managers can determine their age. The number 4, branded on the calf's left hip represents 2004. Calves branded in 1994 have the brand of 4 on the right hip. Calves were also implanted with microchips behind the ear to give each one a unique identification number.

Bison selected for removal from the herd find a variety of homes. Some are provided to Native American tribes; some are transferred to other parks or used in research programs and some are sold at public auction.

Between 60 and 80 animals are snapped up, in sealed bids, to private ranchers. It's estimated that there are now 300,000 bison on private ranches today.