Nesting and roosting osprey are responsible for the closing of an area northwest of Boulder Reservoir know as the Axelson property until Sept. 10.

Boulder Open Space and Mountain Parks also is closing the land adjacent to the Boulder Aeromodeling facility near Boulder Reservoir, however the facility will stay open.

Several areas are closed each year to protect nesting and roosting eagles, falcons and osprey that are monitored by rangers and volunteers.

The Axelson area was closed in 2005 and two pair of osprey successfully fledged young.