For about 2,000 years, flocks of swifts have flown halfway around the world to nest among the ancient stones of Jerusalem's Western Wall.

The birds arrive from southern Africa in late February and stay for about 100 days. Swifts eat, sleep and mate in-flight --- they only nest to lay eggs.

But bird migration expert Yossi Leshem says numbers are dwindling, partly because modern buildings are less accommodating to nesting pairs. The Director of the International Centre for the Study of Bird Migration in Tel Aviv says, "In the last 30 to 40 years, because of modern building they are losing the nest sites, so we want them to be with us in the town, it connects people to the nests. And it connects also the religious to the place because they are in holy places. So that's the point—getting people, religious and wild life together, Muslims, Jews and Christians in one package."

To help rehabilitate the species, experts have mapped 88 nests between the stones of the Western Wall—one of Judaism's holiest sites. And any restoration work done to the wall will take the nests into account. Cameras will be also installed to stream live video feeds on-line. And by the time the birds arrive next year, Leshem hopes to have set up an international project in cooperation with Palestinians, Jordanians and the European Union.