Hawk Hill Fall 2021
The sightings you see here are being collected on a tablet by a biologist out in the field.
Hover your mouse over the points on the graph to see more details. Click on different species in the legend to show or hide them on the chart.
If there's nothing showing, it may mean that this site doesn't have access to the internet or isn't counting right now.
No Reports in the Last Two Hours
Species composition changes over time depending on weather, seasons, and many other factors. This chart displays the composition over a time period you select.
Click on pie pieces to see more detail. If there are more than seven species, click on "Other" to see a breakdown of the rest.
Many sites have a protocol that is designed to maximize finding particular species. If you select "Focus Species," only these species will be shown.
The control box below the pie chart lets you select a date period for the chart.
You can push the buttons "1d," "1w," or "1m" to zoom the graph to 1 day, 1 week, or 1 month.
The graph shows the overall volume seen on each day. You can drag the sliders on each side of this graph to adjust the start and end dates.
August 2nd to October 25th
The time shown in the top row is the start of the one hour period.
Choose a date to load the hourly table for that day. Only days that have data are shown.
These charts show which species are most numerous at different parts of the season. Hover your mouse over a chart to see the number for a given day. The right column shows season totals and the left side shows the maximum for a single day. Each graph is scaled so that the single-day maximum is the highest point on the chart.
- Focus Species: Show the highest priority species at the top of the list.
- Taxonomic Order: Sort the species by their scientific classification.
- Alphabetic Order: Sort the species by their common name.
- Abundance: Sort the species with the largest number counted at the top.
Hawk Hill Fall 2021
The GGRO's autumn hawk count site is located at the northeastern summit of Hawk Hill in the Marin Headlands, Marin County, California. Hawk Hill is a 914-foot hilltop, about 0.20 mile and a 100-ft elevation gain walk from the parking strip on Conzelman Road. This entire lower Marin peninsula is a part of an urban national park, the Golden Gate National Recreation Area, under jurisdiction of the National Park Service. The habitat type surrounding Hawk Hill is coastal scrub, a 3- to 8-foot tall canopy of woody shrubs, primarily coyote brush, although coastal sage, poison oak, and various native grasses thrive here as well. There are few trees here, but primarily non-natives -- Monterey Pine, Monterey Cypress, and Blue Gum Eucalyptus -- and native and wind-bent Coast Live Oaks. The predominant year-round wind direction is from the northwest, with wind speeds averaging just a few miles an hour, but gusting to 30+ mph. During the summer, California's warm Sacramento Valley pulls cool air quickly off the Pacific Ocean creating high western winds, and lots of summer fog. This summer fog in turn supports additional moisture-loving plant species, such as sword ferns and coast redwoods. Hawk Hill is approximately 1/2 mile from the Golden Gate, that is, from the channel between the Pacific Ocean and San Francisco Bay that is spanned by the Golden Gate Bridge. The Golden Gate varies from 1 to 2.5 miles wide, and presumably effects the raptors behavior as they prepare for and attempt the crossing heading from north to south.
From Hwy 101 N of San Francisco Take exit 442 to merge onto Alexander Ave Turn left onto Bunker Rd (1.3 mi for 4 mins) Turn left onto McCullough Rd (0.9 mi for 2 mins) At the traffic circle, take the 1st exit onto Conzelman Rd Park at the top before one-way Rd. (0.6 mi for 4 mins) The hike up to the summit of Hawk Hill is short, but steep (0.5 miles RT)
Golden Gate Raptor Observatory
For over 30 years, the Golden Gate Raptor Observatory (GGRO) has been a program of the Golden Gate National Parks Conservancy in cooperation with the National Park Service.
About the Data
All data displayed on this site are preliminary and have not yet undergone quality control. Written permission is required to use the data.