Mission San Juan Capistrano is trying to lure back the cliff swallows that haven't nested there for more than two decades.
The Orange County Register reports that mission officials have put up a temporary wall near the church ruins with about 30 nests made from dental plaster underneath an archway. The nests could fit two adult birds and a few hatchlings.
Ornithologist and University of Tulsa professor Dr. Charles Brown says swallows re-use old nests and will move into plaster ones.
Cliff swallows were once common at the mission, perching and nesting on its walls. They have just finished a month-long migration from Argentina and are nesting in Southern California.
The project was unveiled Saturday as part of the St. Joseph's Day & Return of the Swallows Celebration.
