The City of Boulder will implement several seasonal closures in 2022 to protect sensitive habitats that support many wildlife species, including cliff-nesting raptors, bald eagles, grassland-nesting birds, burrowing owls and bats. These closures help many wildlife species that have seen significant population declines successfully reproduce and raise their young.

All designated trails around these closures will remain open. To view an interactive map showing currently-enacted seasonal closures, please visit throughout the year. In 2022, the City of Boulder will institute these seasonal wildlife closures:

  • Cliff-Nesting Raptor Closures Feb. 1 - July 31: City Open Space and Mountain Parks (OSMP) protects habitats, including areas on the Flatirons, for nesting peregrine falcons, prairie falcons, and golden eagles. In 2021, these closures helped nesting peregrine falcons to raise 11 peregrine fledglings. That's the highest number of peregrine chicks raised on city open space since monitoring began in 1986.
  • Burrowing Owls, March 15 - Oct. 31: Burrowing owls are found on OSMP grasslands and depend on prairie dog burrows for their habitat. They are on Colorado Parks and Wildlife's "Threatened and Endangered" list.
  • Osprey, Northern Harrier & American Bittern, March 15 - Sept 10: Osprey, Northern Harrier and American Bittern – a rare type of heron – are found across city public lands managed by the city's Parks and Recreation and OSMP lands. Today, northern harriers are listed as rare in Boulder County and are a species of greatest conservation need in Colorado.
  • Bats, April 1 - Sept. 1: Cliff formations on OSMP lands support maternity colonies of Fringed Myotis and Townsend’s Big-eared bats. These closures help to protect bats while they raise their young and are particularly important for Townsend's Big-eared bats, a species listed as threatened and endangered in Colorado. Several OSMP areas are closed permanently to human use to reduce the chance of people introducing White-Nose Syndrome, a devastating disease that can decrease bat populations.
  • Grassland Ground Nesting Birds, May 1 - July 31: Grassland breeding birds have seen widespread and precipitous declines across North America. OSMP provides habitat for several species of grassland nesting birds, including the Grasshopper Sparrow, Western Meadowlark, Vesper Sparrow, Horned Lark, Lark Sparrow, and Savannah Sparrow.
  • Bald Eagles. Nov. 1 - July 31: These areas are closed to help protect habitat for two pairs of bald eagles and to help them raise their young. Bald eagles are federally protected by The Bald and Golden Eagle Protection Act.

OSMP also has closed several areas along South Boulder Creek to help stem the spread of New Zealand mudsnails. These highly invasive aquatic species reproduce rapidly and can displace native insects that fish rely upon for food, impacting fish populations and the animals that feed on them. 

The city will lift closures enacted to protect raptor nesting habitats, if staff and volunteer monitoring indicate raptors are not present.

With higher visitation occurring across Front Range public lands, OSMP reminds visitors to always recreate responsibly on shared public lands and stay on designated, maintained trails outside of seasonal wildlife closure areas. OSMP rangers patrol seasonal closures regularly and visitors who enter those areas may receive a $1,000 fine.

OSMP trails and trailheads in the Marshall Fire area remain closed. The department understands community members turn to open space for physical and emotional support and is working with Boulder County Parks and Open Space to reopen trails and trailheads as soon as it can. For more information about OSMP trails, please visit