San Mateo County Birding Guide by Sequoia Audubon Society - Printed on October 30, 2026
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Skyline Ridge Open Space Preserve is one of the jewels of the OSP system, and a consistent magnet for rare county birds. The preserve covers an extensive area, but the views, the variety of habitats, and the birds make any time spent here rewarding.
The Skyline Ridge Open Space Preserve can be accessed from a parking lot along Alpine Road (this lot is shared with Russian Ridge Open Space Preserve; see separate entry in this guide). A pedestrian walkway takes you under Alpine Road to Alpine Pond and to some of the best birding areas of the preserve. When you enter the preserve at the Alpine Road entrance, you are likely to be greeted by calls of California Quail, Acorn Woodpeckers, Northern Flickers, Song Sparrows, Steller's and Scrub Jays. Walk on the dirt path around Alpine Lake to see Violet-green and Barn Swallows (summer) dashing over the lake. The Daniels Nature Center on the shore of Alpine Pond is the most concrete example of the interaction of the Midpeninsula Open Space District and the Peninsula Open Space Trust.
You can take the Ridge Trail south and east to the grassland and chaparral areas. This trail gradually climbs about to one of the prettiest overlooks in our local open space preserves, where a metal railing provides a safe lookout over a steep chaparral slope and westward views sweeping all the way to the ocean. This chaparral patch hosted some of San Mateo County's only known Sage Sparrows, in the summer of 2007. From there the Ridge Trail descends to Horseshoe Lake at about 1.5 miles from the Alpine Rd. parking area. A pleasant loop route is possible by returning along the Alternate Ridge Trail, on the east side of the hill between the two lakes, through oak woodlands which are popular with breeding Black-throated Gray Warblers in summer. One or two Red-breasted Nuthatches are often found in the planted pines along this route.
From Alpine Pond, you can also take the Page Mill Trail - which drops about 500' in its mile-and-a-half length - into oak forest for Hairy Woodpecker, Hutton's Vireo, and Bewick's Wren. Flocks of Band-tailed Pigeons fly overhead frequently. If you are lucky, Vaux's Swift (summer) and Pileated Woodpecker may also be seen along this trail; more rarely still, it has produced an occasional Hermit Warbler or Golden-crowned Kinglet for the Palo Alto Summer Bird Count circle. At one time, this trail connected to the similar Lambert Creek Trail which descends from Horseshoe Lake, but that connection was destroyed by mudslides some years ago. Nowadays both trails require a commitment to a rather steep return trip along the same route.
The main entrance to this 2,143-acre preserve is located .9 miles south of the Alpine-Skyline intersection on Skyline, on the site of a Christmas tree farm which still operates under the auspices of the Open Space District. There are three large parking lots here; one designed to accommodate handicapped parking; one for equestrians and their horse trailers; and one for the general public. Horseshoe Lake is easily accessible by wheelchair from the handicapped parking area and by foot or horseback from either of the other lots. You can also access the Ridge Trail from the general parking lot and follow it and other paths to the ranger facility and to Alpine Pond. This parking lot area, adjacent to mixed woodland (and itself a mix of brush and grasslands), has been known to host an Indigo Bunting in recent summers, and in winter large sparrow flocks may contain Lincoln's or even White-throated Sparrows.
Visitors to the preserve can look down from one of its many high points to view a wilderness area comprised of chaparral, coastal scrub, grasslands, small lakes, and mixed evergreen forest. The forest is dominated by Canyon Live Oak, and also includes Coast Live Oak, Douglas Fir, California Bay, Bigleaf Maple, Pacific Madrone, and dwindling amounts of Tan Oak (as Sudden Oak Death works its destructive way through the forest.)
The variety of habitats appears to attract an equally diverse bird population. Summer birding is excellent and many of the birds here are more typical of the Sierras. Pileated Woodpecker, Red-breasted Nuthatch, Western Tanager, Lazuli Bunting, Chipping Sparrow, Red Crossbill, Hermit, Black-throated Gray, MacGillivray's, and Yellow-rumped Warblers have all been seen here in the summer. Black Swifts have been known to pass over the preserve's ridgelines when migrating in May and early June. Lawrence's Goldfinches have made surprise visits at several seasons. Some of our few county records of Calliope Hummingbird, Pinyon Jays, and Lewis's Woodpeckers have also come from the trails of this preserve, and the only modern record of California Condor for the county occurred on August 13, 2004 just a few miles south of this preserve - so be sure to take a second look at all those Turkey Vultures!
Year-round Residents
Canada Goose, Northern Shoveler, Gadwall, Mallard, Ruddy Duck, Double-crested Cormorant (sporadic), Great Blue Heron, Great Egret, Green Heron, Turkey Vulture, Osprey, White-tailed Kite, Red-shouldered Hawk, Red-tailed Hawk, Cooper's Hawk, Bald Eagle, Northern Harrier (most likely in migration), American Kestrel (more common in winter, but has been known to breed here), Merlin (most likely in winter), Peregrine Falcon (most likely in migration), California Quail, California Gull (unusual; seen during grasshopper hatches), Western Gull, Band-tailed Pigeon, Rock Pigeon, Eurasian Collared-Dove, Mourning Dove, Great Horned Owl, Northern Pygmy-Owl, Western Screech-Owl, Belted Kingfisher, White-throated Swift (uncommon), Anna's Hummingbird, Virginia Rail, Sora, Killdeer, Long-billed Curlew (migration and/or unusual), Surfbird (migration and/or unusual), Long-billed Dowitcher (unusual), Spotted Sandpiper, Northern Flicker, Downy Woodpecker, Hairy Woodpecker, Nuttall's Woodpecker, Acorn Woodpecker, Pileated Woodpecker, Black Phoebe, Say's Phoebe (unusual at this location), Hutton's Vireo, Steller's Jay, Western Scrub Jay, American Crow, Common Raven, Chestnut-backed Chickadee, Oak Titmouse, Bushtit, Red-breasted Nuthatch (uncommon), White-breasted Nuthatch, Pygmy Nuthatch, Brown Creeper, Wrentit, Bewick's Wren, Pacific Wren, House Wren, Marsh Wren, Northern Mockingbird, California Thrasher, House Sparrow, House Finch, Purple Finch, Spotted Towhee, California Towhee, Song Sparrow, Savannah Sparrow, Lincoln's Sparrow (more likely in winter), Dark-eyed Junco, American Goldfinch, Lesser Goldfinch, Pine Siskin, American Robin, Western Bluebird (uncommon, open areas), European Starling, Red-winged Blackbird, Western Meadowlark, Brown-headed Cowbird (more likely in summer), Brewer's Blackbird, Common Yellowthroat (more likely in summer)Summer Breeders and Visitors
Pied-billed Grebe, American Coot, Allen's Hummingbird, Vaux's Swift, Caspian Tern, Warbling Vireo, Cassin's Vireo, Pacific-slope Flycatcher, Ash-throated Flycatcher, Olive-sided Flycatcher, Western Wood-Pewee, Tree Swallow, Violet-green Swallow, Northern Rough-winged Swallow, Cliff Swallow, Barn Swallow, Blue-gray Gnatcatcher, Black-throated Gray Warbler, Orange-crowned Warbler, Wilson's Warbler, Hermit Warbler (uncommon, in the highest areas), Nashville Warbler (uncommon, migration), MacGillivray's Warbler, Yellow Warbler, Black-headed Grosbeak, Swainson's Thrush, Bullock's Oriole, Western Tanager, Lazuli Bunting, Grasshopper Sparrow, Chipping Sparrow (uncommon, near the Christmas Tree Farm in the Skyline Boulevard parking area, confirmed on territory in 2012).Winter Visitors
Blue-winged Teal, Green-winged Teal, Bufflehead, Hooded Merganser, Common Merganser (rare at this location), Ring-necked Duck, Lesser Scaup (rare here), Common Goldeneye (rare here), Wood Duck (uncommon), Eared Grebe (rare here), Whimbrel, Herring Gull, Ruby-crowned Kinglet, Golden-crowned Kinglet, Red-breasted Sapsucker, Sharp-shinned Hawk, Northern Saw-whet Owl, Varied Thrush, Hermit Thrush, American Pipit, Fox Sparrow, Golden-crowned Sparrow, White-crowned Sparrow, Red Crossbill (uncommon and irruptive, generally at the higher elevations), Cedar Waxwing, Yellow-rumped Warbler, Townsend's Warbler
In this guide, "rarities" are defined as those species given an County Abundance Code of 4, 5, or 6.
Wild Turkey, Golden Eagle (2011, 2012, 2013, 2014), Bald Eagle (2017), Broad-winged Hawk (1993), Solitary Sandpiper (2012, 2014), Common Poorwill (2011, 2013), Calliope Hummingbird, Rufous Hummingbird (migration), Black Swift (migration), Lewis's Woodpecker (2003-04), Yellow-bellied Sapsucker (2013), Western Kingbird (1977, 2009, 2016), Willow Flycatcher (2011), Pinyon Jay, Horned Lark (breeding records from 1990s), Purple Martin (1975, 2009, 2012, 2022), Townsend's Solitaire (2015, 2016), Chipping Sparrow (2014, 2016, 2017), Lark Sparrow (many times in 70s and 80s), White-throated Sparrow (2014, 2019, 2022), Yellow-breasted Chat (2019), American Redstart (2015), Chestnut-sided Warbler (2015), Palm Warbler (2011), Northern Parula (2012), Yellow-breasted Chat (2019), Bell's Sparrow (2007, 2012, 2018), Indigo Bunting (2007, 2012), Lawrence's Goldfinch (evidence of breeding as of 2014), Evening Grosbeak (2011, 2015)
If you are coming from the north, take Highway 35 (Skyline Boulevard) south from either Highway 92 or 84. Using 84 will save you quite a few miles of winding, though scenic roads. From Highway 101 or Interstate 280 take Highway 84 (Woodside Road) west through the town of Woodside to the intersection of Highway 84 with Skyline Boulevard (Highway 35). Take Skyline south approximately seven miles to its intersection with Page Mill and Alpine Roads. Turn right (west) onto Alpine Road for the Russian Ridge entrance or continue .9 miles beyond the intersection for the main Skyline Ridge OSP entrance. Coming from the south, it is possible to take Page Mill Road from I-280; this pretty but narrow road climbs steeply and winds about, but it also takes you past several more fine Open Space Preserves including Los Trancos (San Mateo County) and Monte Bello (in Santa Clara county).
None: thank you, Open Space District and taxpayers.
Sunrise to about a half-hour after sunset.
Be alert for occasional rattlesnakes in the warmer months. Deer ticks clinging to trailside grasses may be the greater threat due to their ability to transmit Lyme Disease; avoid brushing against the low vegetation to which they cling, and wear a repellent on lower legs if so inclined. If you go very far off-trail into the forest you may come across signs of illegal marijuana cultivation, which has become all too common in recent years. If you see anything suspicious please leave the area immediately, as firearms may be present, and notify the Open Space District and/or Sheriff's Office.
There are restrooms at all parking lots. There is also a restroom just west of the nature center at Alpine Pond. There are no close service stations or restaurants; the nearest ones can be found 7 miles north at the intersection of Skyline Boulevard and Highway 84, and in the town of Woodside.
Mid-peninsula Open Space District can be contacted by phone at 650-691-1200.
Skyline Ridge Open Space Preserve is a hotspot in eBird, with data in twenty-three of forty-eight calendar quadrants, representing 103 species.
Skyline Ridge, with its habitat diversity and multiple water features, attracts all-around naturalists. It is especially important as a site for odes (dragonflies and damselflies) and butterflies. The iNaturalist place marker for the park is well-populated.
Skyline Ridge has proven to be the most popular field trip destination among the many parks along SR35, with eleven scheduled visits. These have accelerated in the recent past, with nine of those field trips having happened since 2013.
Author: Anne Scanlan-Rohrer, Frank Allen, and Jean Allen, Uploaded: