Often mistaken for the remains of a defunct geyser, Soda Butte is actually a mound of travertine (Calcium carbonate} formed more then a century ago by a hot spring. Today only small amounts of hydrothermal water and hydrogen sulfide gas are emitted. Despite its look it is very fragile and it is illegal to remove, deface, or destroy any part of it. I have often photographed it but never liked the end result but when I passed it this timethe presence of the bison on the butte whispered to me...."Stop and shoot". I did and I like it but then I must confess that I have an affinity for bison. I find them interesting and extremely photogenic. This stout fellow still in his winter coat lends a presence to the butte that would sorely be missed had he not been there.