The Boulder Open Space and Mountain Parks department and the U.S. Forest Service will begin enforcing seasonal closures at numerous areas Friday to protect long-established nesting sites for predatory birds.

The areas being closed by the Forest Service are Security Risk, Eagle Rock, Blob Rock and Bitty Buttress in Boulder Canyon, according to a news release.

Boulder Open Space and Mountain Parks is closing the following areas, according to a news release:

Lefthand Canyon Palisades (The Buckingham picnic area will remain open.)

Mount Sanitas, First Buttress (The Mount Sanitas trail will remain open.)

Gregory Canyon Amphitheater

Designated parts of the Third Flatiron

Flagstaff Mountain, north side (The Boy Scout Trail will remain open.)

Skunk Canyon

The Back Porch and The Box

Bear Creek Spire

Fern Canyon (The designated Fern Canyon hiking trail will remain open.)

Shadow Canyon and the Matron (The Maiden will remain open and accessible from the east.)

The Sphinx

Diamond Head and the SoBo Buttress

The entire Mickey Mouse wall

The closed areas provide vital nesting territory for golden eagles and falcons, according to officials.

Signs will be posted at key access points for all of the closed areas in Boulder Canyon. Volunteers and Forest Service staff members will monitor the areas.

The city can issue trespassing violations that could result in 90 days in jail or fines up to $1,000 for those who do not respect the closures within Boulder's jurisdiction.

More information about the closures will be available online at fs.usda.gov and www.osmp.org or by calling 303-441-3440.

The closures will go into effect Friday and are expected to be lifted by July 31.