Hawk Hill (California)
| Hawk Hill | |
|---|---|
  Hawk Hill Location in California  Hawk Hill Hawk Hill (the United States) | |
| Highest point | |
| Elevation | 923 ft (281 m) NAVD 88[1] |
| Prominence | 320 ft (98 m)[1] |
| Coordinates | 37°49′32″N 122°29′58″W / 37.8254839°N 122.4994171°W[2] |
| Geography | |
| Location | Marin County, California, U.S. |
| Topo map | USGS San Francisco North |
Hawk Hilll, a 923-foot (281 m) peak in the Marin Headlands,is located just north of the Golden Gate Bridge and across the Golden Gate strait from San Francisco, California. The hill lies within the Golden Gate National Recreation Area.
It serves as the primary observation point for the largest documented flight of diurnal raptors in the Pacific states. Each autumn, from August through December, tens of thousands of hawks, kites, falcons, eagles, vultures, osprey, and harriers are funneled into the headlands by the peninsular shape of Marin County. Hawks typically avoid flying over water because warm thermals, which provide lift, are scarce. The park's protected abundant populations of small mammals serve as a key resource, supporting the significant number of raptors that visit the Headlands during the fall, but the strong onshore winds hitting the hills of the Headlands provide cold updrafts and hot late summer days provide warm thermals that allow these birds to fly more efficiently.
Volunteers with the Golden Gate Raptor Observatory count and track this fall migration using bird-banding and radio-tracking techniques, all in cooperation with the National Park Service.
Raptor observations
[edit]The following table lists the annual average number of sightings by the GGRO in the Marin Headlands during autumn, for the years 2001–2009.[3]
| Raptor species | Sightings per year |
|---|---|
| Turkey vulture | 9,179 |
| Osprey | 105 |
| White-tailed kite | 92 |
| Mississippi kite | < 1 |
| Bald eagle | 5 |
| Northern harrier | 751 |
| Sharp-shinned hawk | 4,187 |
| Cooper's hawk | 2,427 |
| Northern goshawk | 1 |
| Red-shouldered hawk | 464 |
| Broad-winged hawk | 123 |
| Swainson's hawk | 6 |
| Red-tailed hawk | 9,427 |
| Ferruginous hawk | 22 |
| Rough-legged hawk | 7 |
| Golden eagle | 20 |
| American kestrel | 542 |
| Merlin | 171 |
| Peregrine falcon | 199 |
| Prairie falcon | 8 |
| Unidentified | 1,291 |
| TOTAL | 29,028 |
External links
[edit]References
[edit]- ^ a b "Hawk Hill, California". Peakbagger.com. Retrieved 2014-03-03.
- ^ "Hawk Hill". Geographic Names Information System. United States Geological Survey, United States Department of the Interior. Retrieved 2014-03-03.
- ^ The Pacific Raptor Report #32, Summer 2011.