HOBO temperature-sensing data loggers (hereafter, sensors) were placed under the surface of seven rock glaciers predicted to have the presence (n=4) or absence (n=3) of sub-surface ice in Rocky Mountain National Park and near Niwot Ridge Long-term Ecological Research site in Colorado. Sub-surface temperatures were recorded to evaluate habitat differences among American pika populations. All sensors (model H08 pro, H08, or H02; Onset Computer Corporation, onsetcomp.com) recorded temperature (±0.2° Celsius) every one or two hours for one year starting in September 2018. Each rock glacier received at least one sensor, positioned near the center and near pika sign. Three rock glaciers received an additional sensor positioned near the edge of the rock glacier near pika sign. Sensors were placed at similar depths (~0.75 m) and similar aspects.