FAMED BIRDS HAVE RETURNED SWALLOWS BUSILY MAKING NESTS AT COLLEGE OF CANYONS.

Byline: Susan Abram Staff Writer

VALENCIA - After waiting out a cooler-than-usual start to spring, the Argentinian cliff swallows are slowly flocking back and rebuilding their mud homes at College of the Canyons, where they will breed and visit through summer.

The late start could have been weather-related, bird watchers say, but it could also mark an overall change in where the swallows choose to breed.

``The weather this year may have affected their arrival,'' said college spokesman John McElwain, who added that the first few birds, or pioneers, begin to come to the school in late March, followed by the flock.

``Last year, we initiated a program where we tried to encourage them to nest where we wanted them to nest. That seemed to work pretty well.''

The small, stocky, square-tailed swallows make their way to California from South America each year, and their migration is often most documented at San Juan Capistrano Mission, where they are said to return March 19.

The swallows' return to the college is also well known, and this year's rainfall has produced enough flying insects and water to sustain them until their return in August or September to Chile and Argentina. While in town, the birds will create their trademark gourd-shape mud nests in the crevices of buildings and freeway overpasses. But some watchers say their numbers have declined in the past several years, due to drought and development.

In San Juan Capistrano, where parades, parties and cultural events mark the birds' 6,000-mile migration from Argentina to Southern California, only six new nests have been seen so far this year at the famous mission, said Jim Graves, a spokesman there.

``I've been working in the mission for 10 years now, and the number of swallows has been declining before I was here,'' he said. ``Part of the problem is their nests are very fragile and when some preservation work was done on the mission, some of them were broken. The birds just relocated to other sites.''

Still bird watchers and conservationists say the numbers of cliff swallows altogether are not on the decline. Motorists on Interstate 5 are likely to see nests built along underpasses.

State law prohibits the removal of nests during the breeding season.

There are six species of swallows in California, but the cliff swallow is most adaptable, said Dan Cooper, a conservation biologist based in Los Angeles.

Cooper said despite what bird watchers perceive as a decline, the cliff swallow is adapting to the spread of development.

``What they need is sheer vertical surfaces,'' Cooper said. ``Stucco works for them.''

Susan Abram, [phone]

susan.abram(at)dailynews.com

CAPTION(S):

2 photos

Photo:

(1 -- color) An Argentinian swallow flies between the buildings at College of the Canyons. The birds return to the campus annually to nest among the many concrete buildings, which they find perfect for nesting.

(2 -- color) Two Argentinian swallows begin nest building on a structure at College of the Canyons.

David Crane/Staff Photographer