If Prof. Yossi Leshem has his way, the annual return of the swifts to nest in the Western Wall will become as well known as the swallows coming back to San Juan Capistrano, California, each spring.Every March 19 (the Roman Catholic feast day of St. Joseph) the cliff swallows “miraculously” return to the historic Spanish colonial mission near San Diego. The return of the migratory birds from their winter home in Argentina has been popularized in song by Pat Boone and Glenn Miller, and is celebrated in the town’s week-long Fiesta de las Golondrinas.This Monday at 5 p.m., the Tel Aviv University ornithologist, Jerusalem Mayor Nir Barkat and Amir Balaban, one of the founders of the Jerusalem Bird Observatory, are hoping to create a similar hype for the common swift (Apus apus) as these birds wing back from Africa to their spring home at the Western Wall – one of the migrating birds’ oldest nesting colonies in the world, according to Leshem. In recent years, some 40 pairs of swifts have been spotted nesting in the crevices of the Kotel. The birds are most active toward sunset.“The common swift is a unique bird that spends most of its life on the wing,” explains Leshem, who is the director of the Israel Ornithological Center for the Study of Bird Migration. “It feeds on flying insects, which it hunts in the air, it drinks while flying, it sleeps on the wing and it even mates on the wing at the beginning of the breeding season.”The bird, he continues, “spends most of the time living in South Africa in dense colonial groups and, at the beginning of spring, starts migrating north to its breeding sites. During mid- February, it arrives in Israel, which is known to be one of its first breeding sites, and migrates back to Africa at the beginning of June, immediately after its nestlings have fledged.”Although it is small – it weighs only 35 to 45 grams, according to the ornithologist – the bird is “a superior flier, an aerial acrobat. It has a thin, short body and impressive, long, scythe-like wings with an outstanding aspect ratio.”He adds that “ever since humans have started building cities, the common swift has found our buildings perfect for nesting sites, including ancient holy sites such as churches, synagogues, mosques and temples, and has become dependent on us.”The swift nests at the Western Wall were first studied in 2002 by German avian researcher Ulrich Tigges and the late zoologist Heinrich Mendelssohn, one of the founders of Tel Aviv University. Their map of 88 nesting sites served as a guideline during subsequent work to strengthen the masonry of the 2,000- year-old retaining wall, enabling the bird homes to remain undisturbed.However, the future of the common swift at the Western Wall is not secure, says Leshem. The birds are in competition with the sparrows, jackdaws and pigeons that call the holy precinct home, and are threatened by the ongoing construction work in the area.The Friends of the Swifts Association, headed by Amnon Hahn, is working with TAU and the Society for the Protection of Nature in Israel to safeguard the common swift’s future by saving existing nesting sites and designing and building new ones. In addition, the FSA is setting up educational programs in schools, assisting wildlife rehabilitation centers and carrying out a campaign to increase public awareness of the problems the swifts are facing.