ANN ARBOR—Taking no chance on disturbing a pair of Peregrine falcons nesting in University of Michigan’s Burton Memorial Tower, the University temporarily silenced the 45 tons of bells?until experts advised otherwise.

The Charles Baird Carillon performances will resume Sunday in time for honor’s convocation. School of Music officials believe this is the first time in the carillon’s 70-year history that the bells have ever been silenced. The observation deck will continue to be closed to visitors until further notice.

“This is the first time I’ve seen a Peregrine in Michigan,” said Ned Gramlich, U-M interim provost and an avid birder and member of the Washtenaw Audubon Society.” So we went to the best birders we could find. Their view was that neither the vibrations or sounds of the bells nor the clock chimes would seem to be a problem for the falcons.”

The chimes and bells were silenced last week after U-M President Mary Sue Coleman and Gramlich heard from the local Audubon Society confirming sightings of the birds perched on the tower.

In fact, the birds have been more active than just perching, said Sherri Smith, a U-M professor of art and member of the Audubon Society. She observed the pair in a mid-air courting ritual, which gives additional strength to the theory that these specimens are not just passing through Ann Arbor but have decided to set up housekeeping at U-M. If that is the case, two to six eggs should appear in the nest in mid-May and hatch in mid-June.

Steven Ball, who plays the U-M carillon, said he and his students have definitely noticed evidence of the birds’ presence on the ledges of the tower in the form of the occasional unfortunate pigeon. This adds further to the conclusion that the falcons are here to stay, since pigeon is a prime food source for the birds.

According to the Animal Diversity Web created and maintained by the U-M Museum of Zoology, Peregrine falcons are found worldwide except for rainforests and cold, dry Arctic regions. Preferring open habitats such as grasslands and meadows, the birds favor nesting on cliff faces and crevices, but have recently begun to colonize urban areas because tall buildings are suitable for nesting and because of the abundance of pigeons as prey.

With these new campus residents, Ray Stocking, president of the Washtenaw Audubon Society, recommended that U-M building and grounds crews avoid any attempt at approaching the birds as they will abandon the tower if there is close contact with humans. The falcons can be seen from the top of a parking deck near the tower.

Animal Diversity WebPeregrine on Animal Diversity Web