White-tailed kites, bald eagles, northern harriers, and sharp-shinned hawks are here, so are Cooper’s hawks, red-tailed hawks, and even an occasional merlin, so it must be migration time at Hawk Hill in the Golden Gate National Recreation Area. Every fall, thousands of raptors representing up to 19 species fly across the Golden Gate on their southbound journeys to find or follow prey. At the peak of the season, as many as 800 raptors have been seen here on a single day.
Most raptors avoid flying long distances over open water. Over land they can find prey and safe places to rest, as well as the updrafts and thermals that help them gain and maintain altitude. As the birds move south from their northern foraging and breeding grounds, they are funneled by the ocean on the west and San Francisco Bay to the east into a relatively narrow corridor over the Marin Headlands where they are observed and counted by eager birders and the volunteers at the Golden Gate Raptor Observatory. Some of the birds flying by Hawk Hill continue on to Baja California. A few have been tracked as far south as Argentina.
The Golden Gate Raptor Observatory holds public ‘HawkTalks’ and banding demonstrations during clear weekend days in September and October on Hawk Hill. Information on the observatory’s activities can be found at www.ggro.org.