With Autumn almost here, the Pikas must be in the last stages of harvesting whatever grasses & flowers remain to see them through another mountain winter. Pikas do not hibernate. They travel through the tunnels under the rocks & snow during the winter months, surviving on the plant material they have stored during the warmer weather.
The following photos were taken an hour before sunset and although there didn't appear to be many about, those that were, were busy grabbing whatever vegetation was around. And there was some disappearing into small caves and exiting with food. Hopefully, this was actual harvesting and not raiding another pika's pantry! :)