Calidris ptilocnemis
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In 3 days <5%
The rock sandpiper (Calidris ptilocnemis) is a small shorebird in the sandpiper family Scolopacidae. This is a hardy sandpiper that breeds in the arctic and subarctic regions of Alaska and the Chukotka and Kamchatka Peninsulas. It is closely related to the purple sandpiper that breeds in arctic regions of northeast Canada and the northwest Palearctic, and in the past was often considered conspecific with it.
The rock sandpiper was formally described in 1873 by the American ornithologist Elliott Coues and given the binomial name Tringa ptilocnemis. It was formerly sometimes placed in the genus Erolia, but is now placed with 23 other sandpipers in the genus Calidris that was introduced in 1804 by the German naturalist Blasius Merrem. The genus name is from Ancient Greek kalidris or skalidris, a term used by Aristotle for some grey-coloured waterside birds. The specific epithet ptilocnemis combines the Ancient Greek ptilon meaning "feather" with knēmē meaning "leg". Within the genus Calidris the rock sandpiper is sister to the purple sandpiper (Calidris maritima), and next most closely related to the sanderling (Calidris alba) and dunlin (Calidris alpina).
Four subspecies... Wikipedia →
| # | Park | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Redwood National Park | 🇺🇸 United States | |
| 2 | Great Bear Rainforest | 🇨🇦 Canada | |
| 3 | Pacific Rim National Park Reserve | 🇨🇦 Canada |
| # | City | Country | Daily sighting probability |
|---|---|---|---|
| 1 | San Francisco | 🇺🇸 United States |
Rare
Under 5% of wildlife watchers report a Rock Sandpiper sighting in San Francisco on a given day, based on 56 verified sightings from GBIF citizen-science data. It is the 305th most-seen of the 375 birds we can rate there. Over three days the chance rises to under 5%, if each day is a fresh chance.
Any time of year
In every month with enough records, under 5% of wildlife watchers report a Rock Sandpiper in San Francisco on a given day, so our monthly data shows no clear season.
Between 1 and 4 pm
Across all the parks we cover, that three-hour window holds the most Rock Sandpiper sightings with a recorded time, and about 7 in 10 of them come between 6 am and 6 pm: it is a daytime animal.
Only San Francisco, in our data
San Francisco is the only city on Wallace's Line with enough records to rate Rock Sandpiper sightings: under 5% of wildlife watchers there report one on a given day.
Same genus: Calidris
The closest relatives of the Rock Sandpiper that you can see in San Francisco (genus Calidris, Calidris Sandpipers) are Least Sandpiper (about 20%), Western Sandpiper (about 10%) and Dunlin (about 10%), with each one's daily chance of a sighting.
GBIF citizen-science records
It is estimated from how often the Rock Sandpiper is recorded against all the birds logged in San Francisco (56 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.
