again a bit of useless info being posted by people "guessing" so here you go:
DEVILS TOWER NATIONAL MONUMENT
News Release
May 12, 2011 FOR IMMEDIATE RELEASE 2011-06
Devils Tower Climbing Routes Temporarily Closed to Protect Nesting Falcons
Devils Tower National Monument staff has been monitoring for the presence of nesting prairie falcons on and around the Tower. While individual falcons have been observed, no nesting activity has been documented. To protect potential nesting sites being used by prairie falcons (Falco mexicanus), the National Park Service (NPS) will temporarily close climbing routes along the west face of Devils Tower beginning May 13, 2011. When necessary, such closures are an annual occurrence established under the monuments 1995 Climbing Management Plan, with authority from the Migratory Bird Treaty Act. The areas to be closed include climbing routes on the west face between and including the Vulture and Abject Cathexis (routes #154-176 in the Devils Tower climbing handbook). The Tulgey Wood and El Matador rappel routes are also closed. The west edge of the Tower summit is closed to climbers. The Meadows rappel route remains open and is the recommended rappel route for climbers in this area. Climbing and rappel route closures may change based on the location and behavior of the nesting falcons.
The closure is implemented not only to protect the birds, but also to protect climbers, as prairie falcons are known to defensively dive in order to protect their nests. Prairie falcons are extremely defensive of their nests and are easily driven from an area. The presence of climbers near or above falcon nests is distressing to parent birds. Too much disturbance from climbing activities may force falcons to abandon eggs or chicks.
More than 190 other climbing routes on the Tower remain open. Climbers can find a list of currently closed routes at nps.gov/deto/planyourvisit/…, the park climbing kiosk, climber registration office, visitor center, or administration building.
NPS staff will continue to survey the Tower to determine presence or absence of nesting prairie falcons. Areas without nesting falcons will be reopened by June 1st. Areas with falcon nests will remain closed until young falcons fledge, generally between July 15 and August 1. The closure areas may change based on the location of nesting pairs.
Prior observations suggest prairie falcons use the Tower with an affinity for the west and northeast faces, where pairs nested from 2005 to 2007, and 2010. In 2008, falcons were observed nesting on the south face of the Tower. In recent years, young falcons were observed to have fledged from nests on the Tower in 1996, 1998, 1999, 2006, and 2007. In 2009, the falcons nested and fledged away from the Tower.
Separate from the falcon closure, Devils Tower National Monument has a voluntary climbing closure in effect for the month of June, out of respect for American Indian cultural traditions. For further information on the climbing closures, please contact the monuments chief of resource management, Angela Wetz, at (307) 467-5283 ext 212.