Arenaria melanocephala
Silhouette: Elaine R. Wilson (modified) · PhyloPic
In 3 days ~10% in a week ~30%
The black turnstone (Arenaria melanocephala) is a species of small wading bird. It is one of two species of turnstone in the genus Arenaria, the ruddy turnstone (A. interpres) being the other. It is now classified in the sandpiper family, Scolopacidae, but was formerly sometimes placed in the plover family, Charadriidae. It is native to the west coast of North America and breeds only in Alaska.
It is 22–25 centimeters (8.7–9.8 in) long and weighs 100–170 grams (3.5–6.0 oz). The black bill is 20–27 millimeters (0.8–1.1 in) long and slightly upturned. The legs and feet are blackish-brown with a reddish tinge. The bird is largely black and white in appearance. Breeding-plumaged adults have a black head and breast apart from a white spot between the eye and bill, a white stripe over the eye and white flecks on the sides of the breast. The upper parts are blackish-brown with pale fringes to the wing-coverts and scapular feathers. The belly and vent are white. In flight it shows a white wingbar, white shoulder patch and white tail with a broad black band across it. There is white from the lower back to the upper tail-coverts apart from a dark bar across the rump.
In winter... Wikipedia →
| # | Park | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Channel Islands National Park | 🇺🇸 United States | |
| 2 | Great Bear Rainforest | 🇨🇦 Canada | |
| 3 | Pacific Rim National Park Reserve | 🇨🇦 Canada | |
| 4 | Katmai National Park | 🇺🇸 United States | |
| 5 | Redwood National Park | 🇺🇸 United States | |
| 6 | El Vizcaíno Biosphere Reserve | 🇲🇽 Mexico | |
| 7 | Olympic National Park | 🇺🇸 United States |
| # | City | Country | Daily sighting probability |
|---|---|---|---|
| 1 | San Diego | 🇺🇸 United States | |
| 2 | San Francisco | 🇺🇸 United States | |
| 3 | Anchorage | 🇺🇸 United States | |
| 4 | Seattle | 🇺🇸 United States | |
| 5 | Los Angeles | 🇺🇸 United States | |
| 6 | Vancouver | 🇨🇦 Canada |
| # | Zoo / Centre | Country | |
|---|---|---|---|
| 1 | Monterey Bay Aquarium | 🇺🇸 United States |
Rare
Under 5% of wildlife watchers report a Black Turnstone sighting in San Francisco on a given day, based on 4,494 verified sightings from GBIF citizen-science data. It is the 131st most-seen of the 375 birds we can rate there. Over three days the chance rises to about 10%, and over a week to about 30%, if each day is a fresh chance.
August and October–January
In those months about 10% of wildlife watchers report a Black Turnstone in San Francisco on a given day, against under 5% in February–July and September, the lowest months.
Between 11 am and 2 pm
Across all the parks we cover, that three-hour window holds the most Black Turnstone sightings with a recorded time, and about 9 in 10 of them come between 6 am and 6 pm: it is a daytime animal.
2nd of 6
Of the 6 cities where we can rate Black Turnstone sightings, San Francisco ranks 2nd at under 5%. The best odds are in San Diego (United States, about 10%).
GBIF citizen-science records
It is estimated from how often the Black Turnstone is recorded against all the birds logged in San Francisco (4,494 verified sightings), calibrated against known sighting rates. Figures are rounded to the nearest 10% because citizen-science data supports honest approximations, not decimals, and months with records from fewer than five people show "—". How it works.
