Chatfield Reservoir was completely frozen yesterday 2/11/20 and no sign of the Yellow-billed Loon or its companion the Common Loon. I checked the South Platte Reservoir which still has some open water, but no luck.
If you are birding at Cherry Creek or Aurora Reservoir keep an eye out. The Yellow-billed Loon had been in the Denver area for 3 months.
Gregg Goodrich
Highlands Ranch