Borrego Springs provides a window into the migration patterns of Swainson’s Hawks. Swainson’s Hawks spend winter in Mexico, Columbia, and other parts of South America, primarily in Argentina. In early to mid-February, the first Swainson’s Hawks arrive in the Borrego Valley from Mexico. As the season progresses, the hawks arrive from Columbia and, finally, in April, from Argentina. The journey from Argentina is over 6,000 miles.

During a typical migration there are many thousands of hawks passing through, sometimes hundreds in the sky at the same time. It’s a story of hawks, caterpillars, and springtime wildflowers. The hawks come to feast on the caterpillars of the white-lined sphinx moth and the caterpillars are here to eat the flowers that bloom after winter’s rainfall.

The Borrego Hawkwatch is a group of dedicated volunteers (Citizen Scientists) who are engaged in a study of migrating spring raptors through Southern California. We share the wonders of the migration of one of the most beautiful and interesting hawks in North America: the Swainson’s Hawks. From mid-February through March and sometimes into April, we join together to observe, count, and gather data concerning the migration of the Swainson’s hawks through the Borrego Valley, as they stop to feed on caterpillars before continuing north.