Fossil Creek Reservoir

Fossil Creek Reservoir is a premier bird watching destination in Larimer County, sitting just south of Fort Collins near Interstate 25. Managed by the City of Fort Collins Natural Areas program, this large reservoir and surrounding grassland offer a surprisingly tranquil escape despite the urban proximity. Bald eagles nesting along the shoreline during winter months are the marquee attraction, drawing birders and photographers from across northern Colorado between November and March.

Bird watching at Fossil Creek Reservoir is exceptional year-round. Winter brings bald eagles in impressive numbers, with visitors reporting sightings of seven or more eagles in a single outing, plus red-tailed hawks, Cooper's hawks, and other raptors perching in shoreline trees. Spring features western grebes performing their spectacular mating dances across the water surface. Summer brings double-crested cormorants, great blue herons nesting in visible rookeries, and snowy egrets wading the shallows. American white pelicans, Canada geese, and dozens of duck species round out the waterfowl diversity. Wildlife viewing blinds at either end of the trail system let birders observe without disturbing the animals.

Walking and hiking are the primary trail activities at Fossil Creek Reservoir. The main south-side path is paved and accessible, while additional unpaved trails extend the network to roughly three miles of total loop distance. The terrain is flat and easy, suitable for all fitness levels. Important restrictions shape the experience here: no dogs, no bicycles, no skateboards, and no water access of any kind. Kayaking, paddleboarding, fishing, and swimming are all prohibited. These rules exist to protect the wildlife habitat, and they succeed in keeping the area remarkably quiet and undisturbed compared to other Front Range reservoirs.

Fort Collins Natural Areas hosts organized Eagle Watch events on Fridays and Saturdays during winter, staffed by knowledgeable volunteers who set up spotting scopes, share eagle biology, and help visitors locate active nests. The program also runs star and planet viewing nights and other educational family events throughout the year. All visits are free, and the reservoir is open from sunrise to sunset.

Facilities at Fossil Creek Reservoir include indoor restrooms at the visitor center near the main parking lot, multiple covered picnic shelters with educational signage about local bird species, and scattered picnic tables along the trails. The parking area is spacious and easy to access from East County Road 32 near Eagle Ranch Road. Bring binoculars or a spotting scope, as birds tend to concentrate on the far shoreline. Be warned that mosquitoes and gnats swarm the gravel trails heavily during summer months, and an occasional odor drifts from the nearby water treatment facility. Wind exposure is significant on this open prairie landscape, so dress in layers during cooler months. Spring and early summer wildflowers add color to the grassland sections, and mountain views stretch across the entire western horizon on clear days.