Columbian mammoths lived 10,000 to 1 million years ago.
They migrated to North America and as far south as Nicaragua.
Approximately 15,000 years after the nursery herd was trapped, these animals also appear to have been victims of rising water, unable to escape due to the slippery slopes of the surrounding channel.
Luminescence dating of the fossils was done by optically stimulated luminescence (OSL).
The site is the largest known concentration of a single herd of mammoths dying from the same event, which is believed to have been a flash flood.
A local partnership developed around the site after the initial bone was discovered.