The famed Cliff Swallows that migrate to and from San Juan Capistrano in California are about to make their annual flight to Argentina.
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As you can read below, the swallows' journey is an arduous one:
The annual migration of Cliff Swallows from San Juan Capistrano, California, to Goya, Argentina, is a remarkable journey covering approximately 6,000 miles. These birds are well-known for their agility in flight and their distinctive forked tails.
Timing of the journey
- Departure from San Juan Capistrano: Around October 23rd, coinciding with the Day of San Juan.
- Arrival in Goya, Argentina: For the winter, typically by October.
- Departure from Goya, Argentina: Around February 18th, in successive bands.
- Arrival in San Juan Capistrano: Around March 19th, coinciding with St. Joseph's Day.
Flight details
- Distance: Approximately 6,000 miles one way, or 12,000 kilometers.
- Duration: About 30 days one way.
- Speed: Around 18 miles per hour (30 km/hr), utilizing favorable tailwinds.
- Altitude: Above 2,000 feet (6,600 feet) to take advantage of faster currents and avoid predators.
- Energy source: Swallows build up fat reserves before the journey which acts as fuel for their long flights.
Route details
- Initial route from Goya, Argentina: Follows the valleys of the Paraná and Paraguay rivers towards Lake Mirin, leveraging air currents moving towards the equator.
- Later route: Changes westward towards the valleys of the Andes mountains.
- Crossing the Equator: They fly at higher altitudes to benefit from air currents moving north.
- Northward route: Do not cross the Andes until reaching the Gulf of Mexico, then traverse the Yucatan peninsula and fly along the Baja California coast, finally entering the Riverside valley in California.
Arrival in San Juan Capistrano
Historically, the Cliff Swallows would nest under the eaves and archways of the Mission San Juan Capistrano. However, due to increased development in the area, leading to habitat loss and reduced insect populations, swallows have increasingly nested elsewhere and their numbers at the Mission itself have dwindled in recent years. Despite this, the return of the swallows remains a cherished tradition in San Juan Capistrano.
The Ink Spots, featuring Bill Kenny, first recorded "When the Swallows Come Back to Capistrano" in May 1940. The song was written by Leon René in 1939. The recording by The Ink Spots reached number 4 on the US charts