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Fall Bird Migration in California

The Pacific Flyway's winter terminus: refuge auto tours in the Sacramento and San Joaquin valleys where white geese appear in October and cranes build to tens of thousands by Thanksgiving, and a headland above the Golden Gate that carries the largest raptor flight on the Pacific coast.

Agency viewing sites
6
Species documented
7
Mapped
6
Where to stand

Public viewing sites in California

Every place below is one an agency itself describes for watching the fall passage, with the agency named and linked, the species it documents there, the months it names as the peak, and the facility that exists: a tour route, a platform, a tower, a visitor centre. Where the agency wrote a sentence worth reading, it is quoted exactly.

Sacramento National Wildlife Refuge, auto tour route FederalMarquee site

Managed seasonal wetlands and uplands in the Sacramento Valley, south of Willows off Interstate 5

Snow gooseRoss's gooseGreater white-fronted goose

The refuge says waterfowl are present September through April and regularly peak at over 500,000 ducks and 250,000 geese; pintails arrive from mid-August, white-fronted geese follow in September, white geese appear in October, and duck and goose numbers peak on the complex in November and December. The 6 mile auto tour is open one hour before sunrise to one hour after sunset year round, with two observation decks and park-and-stretch areas; pedestrians may not walk the route elsewhere. A $6 daily or $12 annual pass applies, and the visitor center at 752 County Road 99W keeps limited hours, posted on its page.

“White geese (Snow and Ross's) begin to appear in October as fall migration kicks in to full swing.”
US Fish and Wildlife Service, Sacramento National Wildlife Refuge, quoted exactly.

Run by US Fish and Wildlife Service

Merced National Wildlife Refuge, auto tour route FederalMarquee site

Wetlands, grassland and cropland in the Grasslands Ecological Area of the San Joaquin Valley, south of Merced

Sandhill craneSnow gooseRoss's gooseGreater white-fronted goose

The refuge describes the largest wintering populations of lesser sandhill cranes and Ross's geese on the Pacific Flyway, with as many as 20,000 cranes and some 60,000 Arctic-nesting geese, cranes arriving from mid-September, snow geese from late October into November and Ross's and white-fronted geese in November. A 5 mile self-guided auto tour route and four nature trails are open daily year round with no fee.

“Over 15,000 Sandhill cranes are in the Grasslands by Thanksgiving”
US Fish and Wildlife Service, Merced National Wildlife Refuge, quoted exactly.

Run by US Fish and Wildlife Service

Woodbridge Ecological Reserve, Isenberg Crane Reserve, south viewing area State

Flooded fields and freshwater marsh on the edge of the Sacramento-San Joaquin Delta west of Lodi

Sandhill crane

The state agency says the crane wintering season starts in late September and runs docent-led tours at the north site, which has a viewing shelter and is otherwise open by tour only; reservations open at 9 am on the first working day of each month for the following month. The south site at 7730 West Woodbridge Road is open to the public at all times, with a viewing mound reached by a concrete ramp and two accessible parking spaces at the pedestrian gate. A CDFW Lands Pass is required for anyone 16 or older without a valid hunting or fishing license.

“Family-oriented tours are available during the Sandhill Crane wintering season, which starts in late September.”
California Department of Fish and Wildlife, quoted exactly.

Run by California Department of Fish and Wildlife

Hawk Hill, Marin Headlands, Golden Gate Raptor Observatory count site Public platform

914 foot coastal scrub hilltop above the Golden Gate in Golden Gate National Recreation Area

Broad-winged hawkSharp-shinned hawk

The National Park Service calls the Marin Headlands the biggest known raptor migration in the Pacific United States and puts the best viewing at midday in September and October, with hawk talks and raptor releases for the public through the autumn. The Golden Gate Raptor Observatory counts from August 15 to December 5 at the northeastern summit, a 0.2 mile walk with about 100 feet of climb from the parking strip on Conzelman Road; HawkCount averages show about 3,200 sharp-shinned hawks and 160 broad-winged hawks a season, the West Coast's main broad-wing passage.

“The best time to see raptors at Hawk Hill is during midday hours (from 10 am to 2 pm) in September and October.”
National Park Service, Golden Gate National Recreation Area, quoted exactly.

Run by Golden Gate Raptor Observatory, a Parks Conservancy programme in cooperation with the National Park Service

Lower Klamath National Wildlife Refuge, auto tour route Federal

Shallow marsh, open water and cropland on the Oregon line in the Klamath Basin, west of Tulelake

Sandhill craneTundra swan

Peak months as the agency page describes them.

The refuge says about 80 percent of the flyway's migrating waterfowl pass through the Klamath Basin on both spring and fall migrations, that it is a fall staging area for 20 to 30 percent of the Central Valley population of sandhill cranes, and that wintering populations include 30,000 tundra swans; no months are stated. Refuge grounds are open seven days a week from sunrise to sunset with an auto tour route, and the Klamath Basin complex visitor center at 4064 Hill Road, Tulelake, is open Tuesday through Saturday, 9 am to 4 pm.

“The refuge is also a fall staging area for 20 to 30 percent of the central valley population of sandhill crane.”
US Fish and Wildlife Service, Lower Klamath National Wildlife Refuge, quoted exactly.

Run by US Fish and Wildlife Service

Pixley National Wildlife Refuge, observation platform Federal

Seasonal wetlands and alkali grassland in the southern San Joaquin Valley, southwest of Pixley

Sandhill crane

The refuge says cranes begin arriving from northern nesting grounds in September and that numbers may peak at around 6,000 birds by January, and puts the best time to observe them in late winter and early spring. A photo blind and a trail to an observation area serve visitors; the refuge page gives no hours or street address.

“Cranes begin arriving from northern nesting grounds in September and numbers may peak at around 6,000 birds by January.”
US Fish and Wildlife Service, Pixley National Wildlife Refuge, quoted exactly.

Run by US Fish and Wildlife Service

The map

California sites, refuges and the reporting record

Style
Records
Layers

Viewing sites in California, with the national wildlife refuges in the state drawn underneath. The coloured grid is where people have uploaded a verified sandhill crane record to iNaturalist in September, October, November and December, brighter where more have been logged. It is a map of reports rather than of birds: it thickens around refuges, car parks and towns because that is where observers stand, and it shows past reports rather than birds present today. Pins are public viewing sites an agency itself describes; grey dots are US Fish and Wildlife Service refuges and hatcheries, drawn because the refuge system is where most of the staging happens.

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When

When the passage peaks in California

US Fish and Wildlife Service, Sacramento National Wildlife Refuge puts the California peak at white geese appear in October and duck and goose numbers peak on the Sacramento refuges in November and December; the Merced refuge has more than 15,000 sandhill cranes by Thanksgiving; the Hawk Hill raptor flight peaks in September and October. That describes a pattern across past autumns. The week itself swings with the weather: a cold front to the north moves cranes and geese south in a single night, and a warm spell holds them for weeks. Dawn and the last hour before dusk are when cranes and geese move between the fields and the water, and that movement is the spectacle the platforms are built for.

California is where the Pacific Flyway's fall migration stops being a passage and becomes a winter. The Sacramento refuge complex writes the chronology out by species: pintails from mid-August, white-fronted geese in September, snow and Ross's geese in October, a November and December peak of half a million ducks and a quarter million geese, then dispersal across the valley as winter rains flood new ground. South of the Delta the Merced and Pixley refuges and the state's Woodbridge reserve hold lesser sandhill cranes from mid-September, and the Klamath Basin on the Oregon line stages a fifth to a third of the Central Valley's cranes on their way down. The raptors take a different line: hawks avoiding the open water of the Bay funnel over Hawk Hill in the Marin Headlands, where the National Park Service and the Golden Gate Raptor Observatory have counted them every autumn since 1986.

Below, one curve per species the agencies document in California: every research grade observation members of the public have uploaded to iNaturalist for the state, by calendar month across every year the platform holds, with September to December shaded. Counts of uploads, so they measure observers as well as birds, and the shape is worth reading where the absolute numbers are not.

Sandhill crane

5,339 research grade sandhill cranes observations have been uploaded to iNaturalist for California across every year the platform holds, and 52 percent of them fall in the four shaded autumn months. The busiest month in the record is November. An autumn month carries about 2.13 times as many uploads as an average month outside autumn. People upload most of everything in April, so a bar that rises after that is the stronger signal. Counts of what people reported, measuring observers as well as birds. See the autumn records.

Snow goose

7,080 research grade snow geese observations have been uploaded to iNaturalist for California across every year the platform holds, and 43 percent of them fall in the four shaded autumn months. The busiest month in the record is January. An autumn month carries about 1.53 times as many uploads as an average month outside autumn. People upload most of everything in April, so a bar that rises after that is the stronger signal. Counts of what people reported, measuring observers as well as birds. See the autumn records.

Ross's goose

1,981 research grade Ross's geese observations have been uploaded to iNaturalist for California across every year the platform holds, and 49 percent of them fall in the four shaded autumn months. The busiest month in the record is December. An autumn month carries about 1.91 times as many uploads as an average month outside autumn. People upload most of everything in April, so a bar that rises after that is the stronger signal. Counts of what people reported, measuring observers as well as birds. See the autumn records.

Greater white-fronted goose

8,032 research grade greater white-fronted geese observations have been uploaded to iNaturalist for California across every year the platform holds, and 47 percent of them fall in the four shaded autumn months. The busiest month in the record is January. An autumn month carries about 1.78 times as many uploads as an average month outside autumn. People upload most of everything in April, so a bar that rises after that is the stronger signal. Counts of what people reported, measuring observers as well as birds. See the autumn records.

Tundra swan

1,929 research grade tundra swans observations have been uploaded to iNaturalist for California across every year the platform holds, and 56 percent of them fall in the four shaded autumn months. The busiest month in the record is December. An autumn month carries about 2.53 times as many uploads as an average month outside autumn. People upload most of everything in April, so a bar that rises after that is the stronger signal. Counts of what people reported, measuring observers as well as birds. See the autumn records.

Broad-winged hawk

161 research grade broad-winged hawks observations have been uploaded to iNaturalist for California across every year the platform holds, and 76 percent of them fall in the four shaded autumn months. The busiest month in the record is September. An autumn month carries about 6.26 times as many uploads as an average month outside autumn. People upload most of everything in April, so a bar that rises after that is the stronger signal. Counts of what people reported, measuring observers as well as birds. See the autumn records.

Sharp-shinned hawk

3,093 research grade sharp-shinned hawks observations have been uploaded to iNaturalist for California across every year the platform holds, and 51 percent of them fall in the four shaded autumn months. The busiest month in the record is December. An autumn month carries about 2.1 times as many uploads as an average month outside autumn. People upload most of everything in April, so a bar that rises after that is the stronger signal. Counts of what people reported, measuring observers as well as birds. See the autumn records.

Sandhill cranes flying in a loose line across a pale open sky, necks held straight out in front and long legs trailing behind them
Sandhill cranes crossing a refuge on the morning flight. The movement is watched from the designated pullout or platform: the birds settle on shallow water for the night, and the roost itself is the one place a viewing site is never placed. “Sandhill cranes flying over Sherburne National Wildlife Refuge (24542820818)” by USFWS Midwest Region from United States, CC BY 2.0
Latest reports

What people have reported in California lately

The most recent research grade autumn observation of each species that anyone has uploaded to iNaturalist for California, as a date and the platform’s own coarse locality. Evidence that people do find sandhill crane and snow goose here. Each is one bird on one past day: the flocks move with the weather, so where they are this week is what the agency page and its counts answer.

Checking the most recent autumn uploads for California on iNaturalist...

Where California counts are published

Organised events

Festivals and staffed weekends in California

A staffed event is the easiest introduction to this: somebody has already found the birds, set up a scope and can say what is in view. Most organisers publish the dates only weeks ahead, so what follows names the organiser and the recurrence, and the organiser’s page carries this year’s date.

Lodi Sandhill Crane Festival

annual, early November; November 6 to 8 in 2026

Wildlife tours, workshops, presentations and an art show at Hutchins Street Square in Lodi marking the return of cranes to the Delta, with tours to Woodbridge Ecological Reserve and nearby refuges.

Dates are published by the organiser each year Lodi Sandhill Crane Association, with the City of Lodi

Elsewhere

Other states with agency designated migration viewing

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Questions about California

Inventory compiled 2026-09-19 from the agency pages linked above. Agency text is quoted exactly with its source named and linked; the observation curves and latest reports are counts and dates from public uploads to iNaturalist.

Winter eagle watching in CaliforniaThe same refuges and rivers three months later, when the ice concentrates the eagles.California waterfowl seasonThe hunting calendar on the same marshes, worth knowing before standing on a dike in October.California daylight hoursThe dawn and dusk flights are the spectacle, and the clock change moves them.