Base flow monitoring for stream temperature and intermittency at Baca National Wildlife Refuge

The Baca National Wildlife Refuge is located in the San Luis Valley of South-central Colorado on the western flank of the Sangre de Cristo massif, northwest of the Great Sand Dunes National Park. Wildlife managers at the refuge are tasked with protecting two fish species of special concern, the Rio Grande Chub (Gila pandora) and the Rio Grande Sucker (Catostomus plebeius). The U.S. Geological Survey (USGS) collected surface water data with Stream Temperature, Intermittency, and Conductivity (STIC) instruments deployed at the Baca NWR from 2016?2019. STIC instruments are unique for this type of investigation for the purpose of simultaneously collecting temperature data and an electrical resistance signal to determine the presence or absence of water. At each monitoring site, individual raw data records were first screened for the presence of liquid water. All other data points (i.e. drying events, freezing events, etc.) were trimmed from this data set. Second, all water temperature data was calculated from 30-minute resolution to the standardized biologically relevant daily (maximum 2-hour daily maximum) and weekly (maximum weekly average temperature) summary metrics. This summary data provides Baca wildlife managers with the current inventory of available fish habitat, the thermal suitability of the aquatic habitat for both survival and successful recruitment, and to identify possible thermal and or entrainment risks to these fish populations.