Most of us are aware of the famed Mission at San Juan Capistrano and the return of the swallows by the thousands during the month of March. More precisely this was supposed to happen on March 19th or St. Joseph’s Day. Truth be known, today there are very few swallows actually nesting at the mission. As a result of the earthquake of 1812 much of the roof collapsed where the two story arches of the great stone church were left bare and exposed. During reconstruction the nests were removed to protect the swallows. As luck would have it, the swallows moved to other adjacent locations, created new nests, and few have ever returned to the mission.
The fabled swallows of San Juan Capistrano still arrive in the area every year though most of their nests are under local bridges or often under the eaves of local establishments. The photos here are from the nearby Tree of Life Nursery adjacent to Casper’s Regional Park off Ortega Hwy about 15 minutes east of the mission. (Young looking out of its nest shown on the left)
As a naturalist and bird watcher it seems to me that the exact arrival date on the morning of St. Joseph’s Day and then their departure on The Day of San Juan, October 23rd is probably more of an approximation than rule. These dates are still a fair general timing for these little world travelers. At their fall departure these little swallows head for their winter home in Argentina!
The little swallows, more precisely Cliff Swallows, have many more surprises than just their extensive travels. They are very social and live mostly in colonies. These colonies can number as many as 3,700 nests in one location. Although more numerous in the west, they range across the US. As a co-operative species, during poor weather conditions the bird makes a specific call that alerts the other swallows of the colony of the presence of bugs – their primary food. The other members of the colony will subsequently follow the member that discovers the food. (Adult looking out of its nest shown on the right)
Cliff Swallow nests are built by both the male and female although the male may start building before actually attracting a mate. One to six eggs are laid in the nest and both parents incubate the eggs and feed the young. It is a fairly quick hatch of usually in under 19 days. One of the interesting details is that sometimes the adult will lay an egg in another swallow’s nest or even take one of its eggs and move it over to another swallow’s nest. The care of the young is done by both parents or the “adopting parents” which continues for about five days after the young fledges. In such large flocks it would seem difficult to know who were your chicks. The young are indeed recognized by the adults by their call.